Volume 46

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The Use Of Genetic Engineering Methods In Breeding Ornamental Plants

Author: Stephen F. Chandler

PP: 43

From the mid 1980s the use of recombinant DNA technology for plant improvement began to be developed commercially. Now, genetic modification methods can access genes for disease and insect resistance, modification of biochemical pathways and herbicide resistance from a much wider range of sources than previously available. Plant varieties can be modified with no loss of the original parental phenotype, saving many generations in back crossing. Genetic engineering programs in the ornamental area are focused on improving agronomic quality (e.g. disease resistance, keeping quality, pest resistance) and creating novelty (e.g. form, colour) in the important cutflower and pot plants crops. Progress in these areas will be reviewed. From the context of commercialisation, the areas of intellectual property, patent ownership (as opposed to plant breeder rights), government regulation of genetic engineering, and public perception of genetic engineering are central and will be briefly reviewed.
Research and Development in Horticulture: What Should Be Funded and How Should it Be Adopted?

Author: Jolyon Burnett

PP: 77

INTRODUCTION

The public sector has a long history of involvement in rural research and development in Australia through the state departments of agriculture, universities and various other State and Commonwealth funded bodies. However, until the establishment of the Horticultural Research and Development Corporation (HRDC) as a commonwealth statutory authority in 1988, there had been no formal and specific mechanism for support for R&D in horticulture that encouraged direct industry contributions.

This relatively new industry equity in, and ownership of, the R&D has significant implications for the direction, development, conduct, and commercialisation of the program. This paper will focus on two specific implications:

  1. What research gets funded?
  2. How can we best ensure that outcomes are adopted?

However, before these issues can be adequately explored, it is important to have some understanding of the role and operation of the Corporation. The Corporation's mission is to improve

Seasonal Changes in Adventitious Root Formation in Stem Cuttings of Prosopis alba

Author: Sheila Bhattacharya, Allan Dunstan

PP: 398

Seasonality in rooting response of stem cuttings in relation to exogenously applied K-IBA was studied in nitrogen-fixing trees of genus Prosopis (mes-quite). Cuttings of field-grown trees were successfully rooted using an intermittent mist propagation bench during a period of high temperature and relatively higher humidity levels (May to September) than in winter months. The adventitious root formation on cuttings was inhibited during the dormant period (November to February). The efficacy of exogenously applied K-IBA concentration varied with the position of cuttings on the stem. An increasing concentration of applied K-IBA appeared to be correlated with the apical and basal end of the cuttings for the optimum root initiation and development.
A Straight Line Approach to Minimising Water Stress in the Propagation Environment

Author: C.B. Christie

PP: 405

INTRODUCTION

The vegetative propagation of plants by leafy cuttings requires the grower to control turgidity and water loss until roots form. While the importance of maintaining turgor is recognised, even a slight water deficit which may go undetected with no visual symptoms of distress can result in considerable delay or reduction in the rooting response (Evans, 1952; Loach, 1977). Cuttings are most visibly prone to moisture stress and wilting in the first few days that follow severance from the stock plant. Understanding the underlying physiological processes influencing water requirements by cuttings can create opportunities for plant propagators to improve their cutting strike rate through changes in their methods in ways that suit their particular situation.

Water loss from cuttings and hence water stress can be influenced by three interrelated factors: (1) the vapour pressure difference between the leaf and the surrounding air; (2) the resistance to water movement through

Plant Tissue Culture, Dispelling the Mystique

Author: Brian J. Callaghan

PP: 415

INTRODUCTION

I have been involved in commercial propagation of plants using tissue culture techniques since 1981. Over these last 15 years, I have seen a dramatic change in our nursery customers' attitudes towards the use of tissue-cultured plants. The need to produce plants in a cloistered environment of a laboratory decked out like an operating theatre, has made it difficult for the average propagator to relate to tissue culture in a similar way as she/he would when producing plants by traditional cuttings or by seed propagation. Nowadays these techniques are used as an everyday tool to bulk up certain lines. In this paper I will discuss the simple steps in the tissue culture process and try to dispel some of the associated myths.

I intend to use the main crop produced at Lifetech Laboratories as an example of how tissue culture can be applied to commercialise this important crop.

Division, Factors for Consideration in Ensuring Success

Author: Ian R. Gear

PP: 418

In the course of a year, we divide a significant number of Hemerocallis, Hosta, and Iris cultivars.

There are a number of basic tenets that should be followed to ensure success when propagating by division. I propose to deal with each in turn and cite pertinent examples relating to each.

Japanese Taro, a New Zealand Perspective

Author: J.M. Follett, J.J.C. Scheffer

PP: 421

INTRODUCTION

Taro (Colocasia esculenta) is a member of the Araceae family and a native of Northeast India or mainland Southeast Asia (Matthews et.al., 1992). It has been widely naturalised and is now a common food source throughout the tropics and warm temperate zones. Taro was also widely used by Northland pre-European Maori (Matthews, 1985).

Taro is primarily grown for the corm or swollen stem base it produces, although the stems and leaves of some cultivars can also be eaten. The corm and stem contain calcium oxalates so they must be peeled and cooked before eating. There are two main types: the common taro (C. esculenta var. esculenta) which produces one large corm and is imported into New Zealand from the tropics, and Japanese taro (C. esculenta var. antiquorium) which produces many smaller corms (Purseglove, 1974) and is tolerant of a more temperate climate and therefore likely to be more suited to production in New Zealand. Japanese taro can grow to heights of 1.0 to 1

Preparation and Maintenance of Stock Beds

Author: Kiri Johnson

PP: 425

INTRODUCTION

The important factors for successful propagation are:

  • Vigorous material that is of suitable ripeness.
  • Clean and quick handling of the material keeping it moist and cool at all times.
  • Correct rooting hormones and the application of fungal treatments upon setting.
  • A suitable enclosed environment including warmth and moisture. An appropriate rooting media.
  • A weaning system that is done in a fashion suited to the crop.

As we know these practices are essential for good results but we must always start with appropriate material.

Commercial Options for Disease and Pest Control in Plant Propagation

Author: Mark Stevenson

PP: 428

INTRODUCTION

Most disease and pest problems in the nursery are our own fault.For example most races of Pythium are opportunistic, only a few races are aggressive. Pathogens and pests are present or lurking nearby all the time; we need to keep plants healthy so that they can cope with them.

Sprays are nasty chemicals which are residual and poison our environment. This is how many of the public perceive sprays of agricultural chemicals; it does not really matter if they are right or wrong, it is what they think.

The white-spotted tussock moth eradication programme in the eastern suburbs of Auckland highlights this. The biological insecticide Bt is being used for this programme. We as horticulturalists can appreciate the very low toxicity of this product to all animal life, apart from susceptible caterpillars. However there is much concern among residents of the eastern suburbs with regard to the broadcast aerial spraying and possibility of exposure to the spray.

In my view there is

A Review of Specialised Root Systems, and Their Relevance in New Zealand Nurseries

Author: Michael B. Thomas, Mervyn I. Spurway

PP: 440

INTRODUCTION

It is beneficial to examine how nature endows plants with the ability to survive and grow without fertilisers and often in very impoverished soil conditions. Linderman (1978) at an I.P.P.S. conference several years ago made the point that "no organism in the natural environment can live like a hermit". This referred to the fact that plants usually live in close association with microorganisms. The objective of this review is to describe how the roots of nursery plants utilise these relationships and what considerations need to be taken into account on New Zealand nurseries.

Integrated Pest Management (IPM) is for Plant Propagators Too

Author: Nicholas Martin

PP: 446

INTRODUCTION

There is an international trend towards growing plants in ways that are more environmentally friendly. This covers all aspects from energy use, fertiliser, recycling of materials, and plant protection, especially the use of pesticides. These growing systems are sometimes termed integrated plant production and can be linked to the trend to sustainable agriculture and sustainable land management. Integrated pest management (IPM), is the plant protection contribution to more environmentally friendly plant production. This paper will define IPM, outline the pesticide-resistance problems now facing growers, and the use of IPM in practice. Also included are my thoughts on why plant propagators in Europe are changing to IPM and how it works for them.

Germination Strategies for New Ornamental Species

Author: Peter Jensen

PP: 449

INTRODUCTION

Maximisation of germination is a major part of successful introduction for new species of plants which may prove of some horticultural importance or value. The difficulties associated with importation of live plant materials, (such as seeds and other propagating materials), and the obvious high costs involved leads to the logical conclusion that any strategies which may lead to increased germination rates of seeds particularly, are worthy of investigation. This short discussion will focus on the application of a relatively unusual and apparently not widely known method of enhancing the germination of recalcitrant species, namely "smoking".

Recirculating Subirrigation Systems for Nursery Production

Author: J.K. Mayotte, R. Hall, G. Connellan

PP: 82

Three recirculating subirrigation systems (constant-flow capillary mat, intermittent-flow capillary mat, ebb-and-flow) and an overhead spray irrigation system are being assessed for efficiency of water use and plant production, nutrient use and the amount of nutrient-laden leachate and run-off produced. Results to date indicate that plant growth is as good or greater than on overhead spray, on any of the subirrigation systems and that the subirrigation systems use 30% to 37% less water than the overhead spray. The ebb and flow system has produced the lowest levels (mg litre-1 N) and least fluctuation in leachate and run-off nitrate levels. The ebb and flow system also produces the least fluctuation in E.C. levels.
Propagation of New Zealand Native Flora By Seed

Author: Philip Smith

PP: 453

INTRODUCTION

At Taupo Native Plant Nursery, our primary objective is to produce, hardy ecologically sourced New Zealand native plants. Our production this year is expected to be between 1 and 1.2 million plants. Thus for both practical and economic reasons 90% to 95% of our plants are produced from seed.

For the purpose of this paper I will highlight certain areas that a high level of proficiency is required for native seedling production.

Biological Control and Natural Products as Alternatives to Synthetic Pesticides

Author: Robert Hill

PP: 456

Biological control provides an alternative to the use of synthetic chemicals with the advantages of greater public acceptance and reduced environmental contamination.
A Plantsman's Perspective of our New Biosecurity Protocols "Introductions and Consequences"

Author: Terry C. Hatch

PP: 459

Horticulture in New Zealand spans back many hundreds of years. To be a success the plant growers had to import a number of plants to supplement the meager selection available at hand. Careful cultivation of the imported material was needed and highly skilled plant propagators maintained and selected cultivars over long periods of time.

Forward in time, perhaps 700 years, a new wave of importations have been made. The vast majority of these up to the present day providing food, shelter, and beauty to everyday life, enabling us to add the arts, crafts and culture that we need as a civilised society. The simple fact that we had totally transformed what had been until 1000 years ago, primeval forest with its unique multispecific habitats, into highly cultivated farm land with grasses, livestock, and timber trees, had largely gone unnoticed by most citizens. It is only of recent years ecology and all its connotations has been the thing to be "involved in", even politicians are vaguely

Oaks to Know and Grow:The Promise and Problems of the Genus

Author: Guy Sternberg

PP: 464

INTRODUCTION

The oak genus, Quercus, comprises one of the most useful, diverse, widespread, and fascinating of all genera of woody plants. Unfortunately, the oaks constitute a nightmare for taxonomists, with species that merge and collide like freeway traffic. They can present some complex and frustrating problems for propagators aswell.

No one person ever really has known all the oaks. There may be some 500 species (depending upon how one chooses to define a species in this plastic genus), and potentially thousands of hybrids distributed within, but normally not across, the subtle boundaries of several primary subgeneric groups. Oaks can be large trees or prostrate groundcover plants; they can display brilliant fall colors or be fully evergreen; and they can thrive in, and frequently dominate, habitats ranging from desert scrublands to deep swamps.

Oak Propagation from Start to Finish

Author: Connor Shaw

PP: 469

INTRODUCTION

Possibility Place Nursery was started in 1978 at which time we started to grow native and typical horticultural plant material. Five years later (1982) I decided to eliminate almost all typical nursery stock and concentrate on native woody plants of which oaks would compromise a large percentage of the trees (eight species). I realized the current growing methods would not work. Fortunately a gentleman in Oklahoma named Carl Whitcomb devised a system of growing bottomless containers to grow bags. I have taken much of Carl's system and modified it to our needs.

Container Production of Oaks: A Successful Reality

Author: Bill Hendricks

PP: 471

The production of oaks in the field can pose several problems, most of which begin with the liner. For many species the problem in the past has been availability. With others it has been an insufficient root system or coarse-rooted liners that fail to break uniformly if at all. Oaks are notoriously bad transplanters with frequent high losses due to slow root regeneration.

Conventional field whip production practices take up to 5 years to produce salable plants. In the first year, seeds are sown in fall or spring and seedlings are harvested at 1 or 2 years of age. These seedlings are then lined out in field rows for 1 or 2 more years and then cut back to 2 in. in height in spring to produce a vigorous young whip of 5 to 8 ft. This entire process takes 3 to 5 years to produce a 1-year whip. The resulting plant generally has a coarse root system with little to no fibrous roots and at best recovers slowly and in too many cases not at all. For example, root regeneration in red oak

Oak Production in Alkaline Soil: Advantages of Quercus ×schuettei

Author: Michael Yanny

PP: 473

Oak production is a challenging endeavor. At Johnson's Nursery, alkaline soil conditions and a B&B production system make it even more difficult. Our recent use of Quercus ×schuettei (Q. bicolor × Q. macrocarpa) has made field growing oak trees easier and more successful.

Historically, Q. bicolor, swamp white oak, has been one of the best species of oaks for B&B nursery production and landscape use. It has been easy to transplant because of its relatively fibrous root system. Swamp white oak has shown tolerance to heavy, compacted soils and has an adequate growth rate. Unfortunately, at Johnson's Nursery where the soil pH ranges from 7.2 to 7.6, Q. bicolor usually becomes chlorotic due to nutrient deficiency. Lowering the pH with applications of granular sulfur to the soil has not been a satisfactory remedy for this problem.

Quercus macrocarpa, bur oak, is another oak species with great potential as a landscape plant. This long-lived species has an adequate growth rate and is

Graft Incompatibility in Red Oak: Theory and Practice

Author: Frank S. Santamour Jr, Mark V. Coggeshall

PP: 476

According to a theory of graft incompatibility proposed by the senior author, successful long-term graft unions could only be developed in red oak (Ouercus rubra L.) when stock and scion produced identical cambial isoperoxidase enzyme band patterns. Analyses of peroxidases in the seedling rootstocks and scions of 73 "failing" intraspecific grafts of red oak revealed that 82.2% (60/73) of those grafts could have been predicted as potentially incompatible on the basis of enzyme phenotypes. On the other hand, only 13 of 32 (40%) of grafts that had not shown incompatibility symptoms for 4 or 5 years had the same enzyme bands in stock and scion, while 60% (19/32) did not match. The use of seedlings from any particular tree as rootstocks for scions of that tree might not result in any greater enzyme-matching frequency. Future work to further test the theory and reproduce select clones for a seed orchard is briefly discussed.
Oak Grafting Techniques

Author: Mark V. Coggeshall

PP: 481

INTRODUCTION

The vegetative propagation of oak species via grafting is a fairly efficient means by which valuable germplasm can be replicated for both horticultural and forestry purposes. While softwood cutting propagation, and even tissue culture technologies, have been successfully applied to the genus, at least on the research level, these methods have been generally confined to either just a few species and/or limited in their success to only juvenile plant material. Although it can be argued that mature clones of some species can be successfully rooted via softwood cuttings (Zaczek et al., 1993), the resulting plants may fail to overwinter, or grow very slowly, and may even display plagiotropic-type growth habits. For these reasons, it is quite likely that the propagation of oaks via grafting and budding techniques will be the method of choice for those of us interested in this valuable genus. The purpose of this paper is to provide a short review of the grafting techniques

Preliminary Progress on the Asexual Propagation of Oaks

Author: Jason Griffin, Nina Bassuk

PP: 487

INTRODUCTION

There are many techniques propagators use to induce adventitious root formation on softwood cuttings. The application of auxins and the manipulation of stockplant juvenility and light, however, have proven to be powerful factors in the battle to asexually propagate difficult-to-root woody species by cuttings. The use of root-promoting hormones such as IBA is the most common treatment given to these recalcitrant species; however, the effects of juvenility and light have not been fully exploited as treatments in the cutting bench. Juvenility is the use of explant material taken from the biologically juvenile portions of the stock plant. In a number of species, juvenile tissue is the only tissue which will generate adventitious roots. As an example of the importance of physiological age versus chronological age, cuttings of Douglas fir were taken from 26-year-old trees. Cuttings taken from the bottom third of the trees rooted 71% while those from the top third rooted

Propagation For Zoo Exhibits

Author: John Arnott

PP: 85

A zoo presenting a paper to a plant propagation forum reflects the changes that have occurred in zoos over recent years. The functions of today's zoo exhibit differ markedly from those of the 19th century menagerie. Naturalistic exhibits have become the standard. Whilst propagation techniques used for plant production in zoo exhibits are for the main part standard, the applications can often be unique. Botanically zoological horticulture is vast with some 1000 species of plants introduced to the Melbourne Zoo collection since the master plan was implemented in 1989. Some 60% of this material has been propagated on site. This paper will provide a background to zoological horticulture and discuss the implications and the associated plant production/propagation challenges and opportunities presented.
Looking to the Future

Author: Richard E. Bir

PP: 495

INTRODUCTION

Many changes have occurred since the initial meeting of this Society in 1953. Currently, concern exists regarding whether the direction programs are taking has remained relevant to the membership. Those currently responsible for the I.P.P.S. Eastern Region annual meeting program want to provide meaningful information for the membership. However, it is members who will ultimately determine the future of I.P.P.S.

I was asked to look at past programs from the North American regions. Hopefully, the resulting analysis will provide insight into not only how Eastern Region programs have evolved but also into those of Southern and Western Regions.

The Propagation of Lesser Known and Unusual Maple Species

Author: Peter Podaras, Nina Bassuk

PP: 497

INTRODUCTION

Urban trees are highly valued by urban populations although their lifespan is often severely curtailed. Lack of adequate planting space is perhaps the single most difficult problem that urban trees face as they continue to be squeezed into seemingly impossible situations. Soil in these sites is often quite compacted, preventing root growth while pavement further complicates the situation by preventing precipitation from reaching the root zone. As a result, trees can be left with less than adequate soil moisture for satisfactory growth. What water does get into the root zone may be contaminated by road salt providing even more stress. To make matters even worse, the abundance of concrete in buildings and sidewalks drives soil pH to very high levels limiting the availability of iron, manganese, and zinc (Craul, 1992).

Bare-Root Shade Tree Whip Production in Containers with Special Reference to Red Oak

Author: Daniel K. Struve

PP: 508

INTRODUCTION

The Ohio Production System (OPS), a method for producing shade tree whips in containers, was first described in these proceedings (Struve et al., 1987). Under OPS conditions, seeds are germinated and seedlings produced in SpinOut™-treated quart containers in a heated greenhouse. The greenhouse period lasts 10 weeks, February to May. After the last frost, seedlings are moved outdoors under shade for 1 week and then potted into SpinOut-treated No. 3 nursery containers. After up-canning, whips are produced by tying and staking the terminal shoot as under field production. Growth can be rapid; 2 m (about 6 ft) tall red oak can be produced by October. Whips can be fall transplanted, or overwintered in containers in polyhouses orheld as bareroot material in refrigerated storage and then transplanted in spring. Many species can be produced via OPS (Struve et el., 1994).

One disadvantage of OPS whips is their bulk, relative to bare-root whips. If bareroot whips could be

Ornamental Seed Production in Field Cages with Insect Pollinators1

Author: Mark P. Widrlechner, Craig A. Abel, Richard L. Wilson

PP: 512

RATIONALE

The North Central Regional Plant Introduction Station (NCRPIS), located at Iowa State University in Ames, is one of the primary sites of the U.S. National Plant Germplasm System (Roath et al., 1990; White et al., 1989). The NCRPIS specializes in the management of germplasm of agronomic and horticultural crops and their wild relatives that are primarily allogamous (outbreeding). Each year, crop-specific curators at the NCRPIS regenerate seeds of hundreds of germplasm accessions in the field and under glass, controlling pollination to preserve the genetic integrity of the collections. Pollinations for some crops, such as pumpkins, domesticated sunflowers, and corn, are made by hand. A few others, such as amaranths and chenopods, can be regenerated in plastic tents without special pollinators (Williams and Brenner, 1995), provided there is some air movement in the tents. But most crops maintained at the NCRPIS are insect pollinated in nature and their flowers are tedious

Mycorrhizal Associations and Plant Propagation

Author: Donald H. Marx

PP: 517

INTRODUCTION

All plants of commercial or ecological value can have their "roots" traced back to the forest. All we have done is collect them from the forest, propagate them in some fashion and then plant them in various manmade environments, such as tree plantations, orchards, roadsides, urban landscapes, shopping centers, and pots in the patio. Regardless of where these plants are now growing, they still have the genetic requirements they acquired over some 300 million years of development in forests. Most of these requirements are related to the soil. Forest soils typically have a well-defined surface layer of organic litter, large porous channels caused by roots and animal activity, high amounts of decomposing organic matter, and an accumulation of woody debris on the surface. Most of these characteristics are missing in man-made environments. The perennial root systems of most forest plants support diverse macro- and microorganisms in the forest floor, soil, and rhizosphere

Winter Propagation and Liner Bed Production of Conifers

Author: Michael L. Byers

PP: 522

Whenever we look to new and innovative techniques in plant propagation, we must always consider the principles involved. Those are to provide the optimum conditions and environment for plant growth and development while being as efficient and economical as possible. At Ridge Manor Nurseries we utilize a method for production of Taxus, Thuja, and Juniperus which is not new, in fact it is quite old. It is, however, very economical for us and I wish to explain it to you today. Although I have used other methods and know of other methods which are used, my intent is not to compare different philosophies or practices but to discuss our procedure and explain why it works for us.

Ridge Manor Nurseries is located in Madison, Ohio nestled against the southeastern shore of Lake Erie. While we do suffer from an abundant amount of snowfall annually, the loamy, sandy soils and buffering affect of the lake in spring and fall make for ideal growing conditions for conifers. All of our cutting

Breeding Witchhazel at The Holden Arboretum

Author: Robert D. Marquard

PP: 524

RESEARCH OVERVIEW

Research formally began in 1991 with the addition of staff with advanced training in breeding, genetics, and plant physiology. The centerpiece of research is breeding woody ornamental plants. Complementary work involves: studies related to reproductive biology, genetic diversity, elucidation and utilization of biochemical markers, cytogenetics, propagation, and documentation of the inheritance of important traits.

By formal agreement, The Holden Arboretum acquired the germplasm accumulated by David G. Leach who has been a prodigious breeder of Rhododendron for over 50 years. Acquired in 1986, the plant collection is one of the best for cold-hardy Rhododendron germplasm. Staff were added in 1992 to help bolster research at this satellite research station of over 20 acres which is located within 30 miles of The Holden Arboretum.

A new building was built at The Holden Arboretum to provide research space and greenhouse/headhouse areas to meet the expanding needs

Preventing Frost Heaving of Late-Planted Perennials

Author: Philip L. Carpenter

PP: 528

The information presented in this paper is the result of field observations rather than the collection of research data. Also, the concept of using a cover crop for winter protection of newly propagated plant material such as woody plant seedlings was reported at previous I.P.P.S. Eastern Region meetings by Wayne Lovelace of Forrest Keeling Nursery, Elsbury, Missouri. The methods developed by Lovelace were applied to late planted Hemerocallis divisions (planted after September 30th) to provide winter protection and prevent "frost heaving" of the crowns. Normally Hemerocallis divisions would not be planted in the field after August 30th but in the digging of field-grown Hemerocallis plants for fall containerizing there are also surpluses and grade outs left. These plants represent part of the profit that can be made from the crop so it would be advantageous to save these plants if at all possible; hence the late planting in the field. A major problem that can occur when perennials
Syringa: A Challenge!

Author: Roger G. Coggeshall

PP: 530

It's called enthusiasm. You must have it to go into the nursery business, or you have to be a little crazy. A combination of both works well. We all have our favorites and thank God we all do not agree. One of mine is lilacs, or as they're better known in this group — Syringa. Now if you were my mother, you'd know very well that a Syringa was a mockorange, because her mother told her so! How could it be a lilac? Now I'm no botanist, but I do know a Syringa when I see one.

So you want to propagate Lilacs? Actually there's nothing to it. All you have to do is propagate your selection asexually so it reproduces true to color, size, and vigor. Plant it, prune it, fertilize it, weed it, water it, etc. for several years. Now this all happens while you grow plants that really make you money like red-leaved barberries and pussy willows. So after you've struggled for several years with a group of plants that really interest you, they bloom. Now you've either struggled right from the initial

Trials and Tribulations of Producing Acer pensylvanicum ‘Erythrocladum’

Author: Ken Twombly

PP: 532

INTRODUCTION

Acer pensylvanicum ‘Erythrocladum’ was introduced by Spath Nursery of Berlin, Germany in 1904. It is a fast growing tree with striped green and white bark in summer. Its pendulous racemes of yellowish flowers appear in spring before the foliage. Attractive foliage turns clear yellow in fall. But its most important attribute is its bark, all of which, from the ground up to the tips, starts turning to pink in the fall with the cool weather, becoming a startling bright coral-red during the winter. It is a superb plant for the winter landscape.

This paper is the result of work by two nurseries and one arboretum.

Current Research into Water Disinfestation for the Nursery and Cut Flower Industries

Author: Martin Mebalds, David Beardsell, Andrea van der Linden, Michelle

PP: 89

Water disinfestation in Australian Nurseries has mainly been done using chlorination either from sodium hypochlorite or direct injection of gaseous chlorine. Some nurseries in Queensland and northern Australia have bromination and chloro-bromination systems, and ultra violet light is used in several nurseries in Victoria. An important feature shown in a survey of water quality by Beardsell and James (1995) was that it is vital that nurseries and flower farms do a complete analysis of water quality over a 12-month period before choosing a water disinfestation strategy. A recent symposium on nursery substrate disinfestation held in Belgium (Vanacher, 1995) did not provide clear information on best practices; as few quantitative and economic analyses were presented. The following paper presents a summary of the best available information on water disinfestation for the nursery industry. Much of this information has been generated by projects currently being conducted in Australia.
Economical Fertilizer Applicator: Keep it Simple

Author: Clayton Fuller

PP: 534

Sometimes in this day of high technology we forget that some things are better left simple. We feel that our dispenser does that at a minimal cost. There are no moving parts, nothing to rust, and it is unaffected by weather conditions.

COMPONENT PARTS

  • Rubbermaid vanity wastebasket 10 in. long × 6 in. wide × 10 in. high with rolled edge for better strength.
  • 15-in. automotive funnel.
  • 16 in. length of &frac34-in. polyurethane pipe.
  • 1-in. tiedown strap with adjustable buckle.
  • Two 1-&frac12-in. hinges.
  • 3-in. screen door handle.
Fertilizing Stressed Plants

Author: Charles W. Martin

PP: 536

As growers, we all know our most important tool is our eyes. We are always observing and analyzing growth patterns, color of plants, abiotic and biotic plant damage, and stressed plants in order to produce the healthiest, most vigorous plants possible. The belief has long been that the strongest, healthiest plants were the plants with a vigorous growth rate. We have long emphasized fertilization with nitrogen in order to improve the plants growth and equated this with plant health. However, a fast growing plant doesn't always withstand the stresses of the homeowner's environment.

Dr. Paul J. Kramer, the noted plant physiologist, stated in 1956,"We will learn how to grow trees by learning how trees grow". Dr. Kramer is stating we can't just depend on our eyes to grow healthy plants, we need to understand what occurs within the plant that allows it to grow and survive. When we take a look into the plant's physiological mechanisms we will find that fertilization will often limit a plants

Significance of Mycorrhizal Management in the Production of Trees and Shrubs

Author: Donald H. Marx

PP: 538

INTRODUCTION

Another paper in this Proceedings described the basic biology and the important roles that mycorrhizal associations play in normal growth and development of forest plants. It also emphasized that all commercially important plants, especially woody plants, regardless of where they are grown still have the genetic requirements their species have acquired from the forests over millions of years of evolution. One such biological requirement is abundant mycorrhizal development on their root systems. The purpose of this paper is to discuss factors affecting mycorrhizal development and to present a few examples of some of the worldwide research done on mycorrhizal manipulations of commercially important forest and landscape plants. There are hundreds of publications that could be used in this discussion. However, only a few are used here to show the importance of managing mycorrhizae—the missing part of the forest—in propagation and productivity of these plants in our

Perennial Production in Europe: An Overview

Author: David J. Beattie

PP: 543

INTRODUCTION

The popularity of herbaceous perennials has affected all parts of the ornamental plant industry in the U.S. While perennials were formerly produced only by a small group of specialty growers, today bedding plant and even "woody" nurseries are propagating and growing herbaceous perennials. While domestic production has increased, growers and retailers in the U.S. still depend on seeds, plants, and ideas imported from Europe.

Recent Developments in Seed Germination of Ornamental Herbaceous Crops

Author: Robert L. Geneve

PP: 546

INTRODUCTION

Seed propagation is the major production system for ornamental herbaceous crops. It is also an area of propagation that has seen a tremendous increase in innovative techniques used to enhance quality plant production. Much of this innovation has developed in response to plug production of seedlings. A plug is a seedling grown under near optimum conditions in a small volume of growing medium. This increases production efficiency because more plants can be grown per unit area of greenhouse space. Seed germination is the critical initial event that determines success in plug production. This has led to increased emphasis on seed quality and techniques to enhance seed germination. This review will briefly cover the recent advances in the area of seed germination including:

  1. Seed treatments to enhance germination and seedling emergence.
  2. Seed vigor testing.
  3. Mechanical seed sowing.
Ginseng: Seed Germination and General Culture

Author: Leonard P. Stoltz

PP: 550

INTRODUCTION

American ginseng, Panax quinquefolius, was first discovered in Quebec, Canada in 1704 by Michael Sarrasin and was later rediscovered near Montreal, Canada in 1716 by a Jesuit missionary, Father Lafitau. Father Lafitau began searching for the plant after reading an article written by a Jesuit missionary in China which extolled the medicinal value of the Chinese ginseng, P. ginseng, and suggested that the plant might also occur on the North American continent. Samples of the root were sent to China for confirmation that it was the medicinal plant desired. By 1720 a company was formed to gather, dry, and ship the root to China. Gathering of the wild root continued through the years and by the mid-1800s had resulted in the decimation of wild ginseng in much of its natural range. By the beginning of the 20th century, several individuals were attempting to cultivate ginseng. One of the problems of successful ginseng cultivation involves seed germination, which requires up

Using Computers to Plan Perennial Production

Author: George P. Pealer

PP: 557

I have always considered PLANNING as the first step in perennial production. Using computers to help plan perennial production is a great way to save time and improve accuracy of planning. The main advantage is that using computers forces you to be organized in a logical fashion. Like using many types of computer programs, it will take some time to get used to using a program, but once you have it mastered, it will allow you to be very productive in your planning process.

Some reasons to use a computer program to help you in your production planning are:

  1. Using computers will force you to become organized, and you will become more productive.
  2. There are so many perennials that you should have in your list to have a good product mix. The more plants you have, the more complicated the planning process becomes.
  3. Very few perennials can follow the same production "recipe". Every plant is different, and you may find that a certain crop will not grow the same in successive years, even
Review of Current Practices for Overwintering Container-grown Herbaceous Perennials

Author: Jeffery K. Iles

PP: 560

INTRODUCTION

Most container-grown herbaceous perennials require winter protection if they are to survive low temperatures and wide winter temperature fluctuations typical of many regions in the United States and Canada (Iles et al., 1993). Ideally, overwintering systems should insulate plant roots and crowns from undesirable high and low temperatures, and should buffer rapid temperature fluctuation. Over the last 10 years, researchers have studied several freeze-protection methods for container-grown perennials (Iles et al., 1993; Perry, 1990; Still et al., 1987; Still et al., 1989). However, little is known about which methods growers, retailers, and other nursery and landscape professionals actually favor for sheltering container-grown herbaceous perennials from winter injury. Therefore, the primary objective of this study was to identify and investigate the effectiveness of winter protection systems used by landscape and nursery professionals in U.S.D.A. Hardiness Zones 3

Growing and Marketing Herbaceous Natives

Author: Michael Kolaczewski

PP: 571

INTRODUCTION

The utilization of native plants, in the case of this paper, herbaceous forbs and grasses, has been very popular over the last several years. They are utilized in natural area restoration work; and highway, corporate, and residential landscape projects. Native plants should be considered as an addition to a nurseries production scheme. This paper discusses the methods that are used by the author to grow and subsequently market this type of plant material.

There is no denying that the perennial plant market is at this time, capturing a significant share of the wholesale and retail sales in the horticulture industry. The relative ease of perennial propagation, rapid turnaround in production time, and wide appeal in sales, make this product line worth investing in. With regards to native plants, or in the case of this paper, Midwestern woodland and grassland perennials, they are able to be utilized in various ways to achieve customer sales, and subsequent return

Use of Growth Regulators in Production

Author: Rod Ackerman, Harlan Hamernik

PP: 574

INTRODUCTION

This paper in no way promotes or recommends the use of chemical growth regulators, but rather offers an overview and insight into their potential uses and/ or limitations. When considering growth regulators for plant production, the legal aspects (label restrictions, etc.) and environmental concerns must be taken into consideration.

The effect of any growth regulator is dependent on the method of application, health and vigor of the plant being treated, and the environmental influences during application as well as the cultural and environmental conditions after application. When we mention the term growth regulators, we are referring to chemical or environmental condition that will influence or modify the normal growth characteristics of a plant. The most important growth regulators currently employed at the nursery are cultural rather than chemical. They include:

  • Watering (water can be a great growth inhibitor when employed by a skilled grower).
  • Temperature (low
An Alternative to Methyl Bromide: Electrically Produced Steam

Author: John R. Bunker

PP: 93

INTRODUCTION

The use of aerated steam for pasteurisation and sterilisation is not a new technique in our industry. It first gained interest in Australia following a visit by Dr. Ken Baker in 1960. The release of the UC Manual for Container Growing Plants by Baker led several nursery operators to embrace this technique. Alan Newport (Newports Nursery), Jack Pike (Pikes Nursery), and Gavin Wilton (Falg Nurseries), all introduced aerated steam into their bedding plant and house plant operations in the early 1960s. The traditional users of aerated steam have been the bedding plant and seedling producers, probably because of the critical importance of hygiene in raising seedlings.

In the last 2 years the use of aerated steam has gained momentum again in the nursery industry because of two key issues.

  1. Methyl bromide which has been widely used as a disinfesting agent has been labeled as a serious ozone depleting gas. Through the U.S. Clean Air Act it will be banned from use in the
NEW PLANT FORUM

Author: Jack Alexander

PP: 577

Aster linariifolius

Stiff aster is an August to October blooming perennial from dry acid open areas. This accession was collected in southern Ohio but the species ranges to Maine. It will grow in average to dry soils amended with peat and sand. Plant height is 1 to 2 ft. Easy to propagate from seed when given a 90-day cold moist stratification. Stiff aster can be propagated from new growth cuttings taken in June. Seed is available upon request from The Holden Arboretum.

QUESTION BOX

Author: Ralph Shugert, Bruce Briggs

PP: 583

QUESTION: Is there a safe, labeled herbicide I can use with container-grown Phlox paniculata? I have used Rout, OH II, Regal 0-0, etc. and experienced phytotoxicity.
Practical Ideas and Solutions to Common Problems

Author: H. William Barnes

PP: 585

Resourcefulness and innovation are two sides to the same coin.
  • One grower in the southern part of the U. S. uses plastic soft drink crates as deep flats for the rooting of cuttings.
  • The wounding of cuttings can be troublesome. One solution is a hacksaw blade mounted with the teeth upright so that a cutting can be drawn across it, thereby inducing a wound.
  • An elevated box with a gap along the bottom perimeter mounted onto a farm wagon can easily be converted into an effective mobile potting operation.
  • Stratifying seeds can be a problem. The media, usually, peat or sand, is either too wet or too dry or too sticky and not enough air can get to the seeds. Moist perlite does a lot to eliminate these problems and the seeds come out cleaner and easier to handle. Also it is easy to see if they have germinated in the bag.
  • Lights should be an integral part of mist propagation. Low-wattage incandescent lights mounted 3 ft above the rooting area and set to come on from 10 PM to 2 Am are very
Winter Propagation of Ulmus ‘Regal’

Author: Dan Moore, Bernard Fourrier

PP: 586

Though elms can be propagated from softwood in the summer time or from shoot cuttings taken from pieces of roots stuck in flats in the winter months, we have found that taking "micro cuttings" from canned stock plants forced in a heated plastic house in the middle of the winter to be more reliable and economical.

Preparation of the Stock Plants. The canned stock plants are put in a plastic house in early December. On 1 Jan. the furnace is turned on and the temperature set at about 50 to 60F. On 15 Jan. the stock plants are trimmed on top lightly and re-canned if necessary. These are elms that are 1 to 5 years old. Then they are topdressed with 3–4 month Nutricote 14N-14P205-14K20 at medium rate. On 30 Jan. each can is given Sequestrene 138 Fe at 1 tsp gal-1 and the temperature is raised to 65F.

Preparation and Treatment of the Cuttings. February 15th, the first cuttings are about ready to be harvested. We take the tips from the slower-growing side shoots; they are the best. We remove

Softwood Cutting Propagation of Eucommia ulmoides

Author: David Schmidt

PP: 587

INTRODUCTION

The name Eucommia (eu, well and kommi, gum) is an illusion to the quality of the rubber contained in all parts. Eucommia ulmoides better known as hardy rubber tree is interesting because it is about the only rubber tree that grows and overwinters outdoors this far north. When leaves are torn gently across, the threads of rubber remain and can be easily seen. At the Royal Botanical Gardens in Hamilton two hardy rubber trees have been diligently guarding our east driveway entrance to our center since 1956.

The bark of Eucommia when first discovered in China around 1900 was being used in a medicinal tonic by the Chinese people. Today, rubber yields are found to be too low and difficult to extract compared to the great tropical rubber tree Hevea brasiliensis, thus eliminating it from commercial rubber production. In appearance the tree resembles a 40 ft elm showing off 3-in. long, glossy, alternate, sharply toothed, pest- and disease-free leaves. The plant is dioecious

Use of Sulfentrazone (F6285) for Preemergence Weed Management in Field-Grown Ornamentals

Author: Kimberly Collins, Leslie Weston, Robert McNiel

PP: 589

The nursery industry currently has limited options for effective season-long weed control, because relatively few soil-persistent broad spectrum herbicides are registered for use in ornamentals. Sulfentrazone (F6285), a newly developed herbicide from the FMC Corporation, has shown promising results for preemergence weed control in field trials with ornamentals. Sulfentrazone provides selective control of yellow nutsedge (Cyperus esculentus) and morning glory (Convolvulus) species, as well as broadleaf and annual grass weeds (Weston et al., 1995). When applied at low rates in combination with other efficacious materials, the spectrum and longevity of weed suppression is enhanced (Crotser and Weston, 1995). Additional trials are needed to further evaluate the potential for registration of sulfentrazone for use in ornamentals.

Research was conducted to evaluate preemergence application of sulfentrazone and currently labeled products at different rates in ornamentals. The 17

Hemerocallis (Daylily) Propagation

Author: Winston C. Dunwell

PP: 590

INTRODUCTION

Numerous Hemerocallis (daylily) cultivars are introduced each year that never make it to the consumer market because of limited supplies. The dramatic increase in the number of daylily cultivars and the preference for named cultivars has resulted in daylily propagation being limited to vegetative propagation, except in the case of hybridizers use of seed propagation to grow-out and evaluate the plants produced from their crosses. It has been stated that it can take 20 years for an outstanding cultivar to move from the enthusiast (connoisseur) market to the mass market (Pounders and Garton, 1996). The shortage and subsequent rapid nursery production of ‘Happy Returns’ introduced in 1986 indicated that even if the cultivar forms a relatively large number of divisions per year, it can take 10 years or more to have adequate plants to meet market demand.

Hybridizers have often been caught short of plants when a new introduction proves popular leading some to postpone

Cutting Propagation of Grafted Mature and Juvenile Northern Red Oak

Author: James J. Zaczek, K.C. Steiner, Charles W. Heuser Jr

PP: 595

A rooting trial evaluated the rooting success of cuttings from mature and juvenile, grafted and ungrafted northern red oak (NRO). Buds from seedlings and from 4 mature NRO trees were grafted onto juvenile and mature rootstock. Shoot cuttings were collected from the grafts and directly from seedling and mature trees and subjected to a rooting trial. Of all treatments, cuttings from juvenile material rooted best. However, the rooting of cuttings from mature trees was also relatively successful. Percentage rooting of cuttings was significantly related to ortet genotype and ontogeny and was not directly influenced by grafting. The number of roots per cutting and post-rooting flushing behavior was significantly related to ortet ontogeny. Juvenile rootstock had little effect on the rooting, number of roots per cutting, flushing behavior, and overwintering success of cuttings from mature NRO. Mature rootstock negatively influenced the number of roots per cutting, flushing behavior, and overwintering success of shoots from grafted juvenile buds.
Is Kiek Another Mugwort?

Author: David J. Beattie

PP: 601

Common Name.
      In U.S.A.: creeping field cress
      In Holland: Kiek

Scientific Name.
      Rorippa silvestris
      Brassicaceae family (mustard)

Where Did Kiek Come from?
      Europe
      Introduced into U.S.A. 1818.

Native habitat.
      Stream edges and wet areas
      Ideally suited to nursery/container culture.
      Very winter hardy.

How in the Weed Spread?
      Rhizomes in and on bareroot herbaceous perennials shipped to the U.S.A.
      from Holland or on U.S.A.-grown bareroot and potted perennials.

Examples of Plant Vigor.
      Shoots emerge from 2 to 4 cm depths in 3 to 4 days.
      After 1 month in a greenhouse, as many as three new shoots and more than
      80 root shoots were produced.
      A 3-cm long rhizome segment grew 28 cm from the bottom of a pot.

Herbicide Control.
      No cleared herbicides in U.S.A.
      Repeated Roundup application does not kill.

Post Emergence Control.
      Dutch nurserymen control Kiek with mixture 2,4-D and MCPA.
      Not been cleared for U.S.A.

Other Control Methods.
      Cultivation exacerbates problem.
      Chopping rhizome rapidly propagates

Pest Resistant Landscape Plants

Author: Richard E. Bir, Thomas G. Ranney

PP: 602

Reducing pesticide usage while utilizing attractive landscape plants has been the goal of many research programs. At the Mountain Horticultural Crops Research and Extension Center, we have been evaluating landscape plants for pest resistance under the high pest pressure conditions of the southern Blue Ridge Mountains. Resistance to Japanese beetle foliar feeding and depredations from eastern tent caterpillar on flowering trees plus disease resistance on Cornus kousa and allegedly pest-resistant shrub roses revealed plants displaying a wide range of pest resistance.

Eighty-five different taxa of woody plants were included in these tests. Tables shown here include a representative sample of those plants. For a complete listing of these plants as well as experimental methods, please consult the research papers referenced. The relative terms: poor, fair, good, and excellent were developed for ease of comparison. Poor resistance to disease indicates that the test plant became

Gene Transfer and Interspecific Hybridisation: Two Approaches to Virus Resistance in Papaw (Carica)

Author: Roderick A. Drew

PP: 99

INTRODUCTION

Papaw or papaya (Carica papaya L.) is grown as a fruit crop in countries with tropical and subtropical climates. In 1988 the world production of papaw was 3.68 million tonnes. Papaya ringspot virus (PRSV) is the most serious disease of papaw (Purcifull, 1972) and poses the greatest single threat to papaw production in the world (Litz, 1985). It was first reported on the island of Oahu in Hawaii in 1945 (Lindner et al., 1945) and subsequently occurred in Africa, Bangladesh, Brazil, Colombia, Cuba, El Salvador, Sri Lanka, Venezuela, India, Thailand, Taiwan, and the Philippines. In the nineties it has been reported in Malaysia and South East Queensland.

PRSV is a member of the potyvirus family and infects plants in families Caricaceae, Chenopodiaceae, and Cucurbitaceae. Two closely related strains occur: P and W. Papaws are infected by strain P, which is aphid-borne and spreads rapidly in affected areas. The symptoms of PRSV-P in papaws are vein clearing and chlorotic

Germination and Seedling Development in Pawpaw Asimina triloba

Author: C.L.H. Finneseth, D.R. Layne, R.L. Geneve

PP: 605

Pawpaw [Asimina triloba (L.) Dunall is a small, deciduous fruit tree indigenous to most of the eastern United States. It is the only temperate member of the tropical Annonaceae or Custard Apple family. As a member of this primitive family, its large seeds have a characteristic ruminate endosperm and underdeveloped embryo.

Seed anatomy and seedling development have been outlined for a limited number in the Annonaceae, family (Corner, 1948, Hayat and Canright, 1968). Ovule and seed development as well as seed morphology have been described in pawpaw (Mohana Rao, 1982, Lampton, 1957), but there are no descriptions of morphological changes during seed germination or seedling development. This study was designed to describe important developmental stages during germination and seedling development of pawpaw.

Seeds were extracted from ripe fruit (Keedysville Orchard, University of Maryland, Keedysville, MD), packed in moist sphagnurn moss and stored in plastic bags at 4C until planting

Capillary Mats Modify Media Moisture During Mist Propagation of Chrysanthemum Cuttings

Author: Jennifer Marohnic, Robert Geneve, Jack Buxton

PP: 606

INTRODUCTION

A central feature of the propagation of leafy cuttings is that lacking roots they readily develop water deficits. Slight water deficits, even though insufficient to cause any visual symptoms of distress, can result in considerable delay or reduction in the rooting response (Davis et al., 1988). With the use of intermittent mist, a film of water remains on the leaf surface lowering the vapor pressure deficit and reducing transpirational water loss (Synder and Hess, 1953). However, misting, either applied too frequently or too long at each interval, can result in excessive wetness leading to restricted aeration and reductions in root development (Grange and Loach, 1983b).

Capillary mats can be used to add or reduce the water content of growing media in containers (Buxton and Jia, 1991). In the present study, Vatex capillary mats added or removed water from Smithers-Oasis 1-in. Rootcubes® during mist propagation. The objective of the current study was to evaluate the

Changes in Root Length and Diameter in Plants Grown in Copper-Treated Containers

Author: M. Stafford,, R.L. Geneve, R.E. McNiel

PP: 608

INTRODUCTION

Copper products have been successfully used to control root growth and development in container grown woody landscape plants for several years. Nurseries apply a solution of copper in latex paint to inner surfaces of containers for increased root control enabling improved field establishment and performance of woody landscape plants (Struve, 1993). Copper products control roots by eliminating circling in containers, forcing roots to branch to the center of the container (Arnold and Struve, 1989). The resulting root system is more compact and evenly distributed throughout the container. Increased shoot growth and development after transplanting has also been reported in several plant species produced in copper-treated containers (Arnold and Struve, 1989). In the past, researchers have relied upon gravimetric measurements to evaluate root systems. Observation of roots exclusively by root dry weight can provide misleading information due to differences in allocation

Stock Plant Shading to Increase Rooting of Paperbark Maple Cuttings

Author: Brian Maynard, William Johnson, Thomas Holt, Dixon Hoogendoorn

PP: 611

INTRODUCTION

Acer griseum, the paperbark maple, is a lovely small tree with year-round interest but is relatively scarce in the nursery trade because of slow growth and difficulties in propagation. Propagation is mostly from seed, though seed production is often poor or unpredictable due to problems with poor seed fill and sterility. Grafting paperbark maple is difficult and generally impractical. In 1985, Dixon Hoogendoorn recounted to the I.P.P.S. membership his experiences with propagating paperbark maple from cuttings (Hoogendoorn, 1985). Using stock plants, of seedling origin, that had been cut back (hedged) for many years, he was able to obtain, predictably, 60% rooting of softwood cuttings taken in late June (Rhode Island).

It would be commercially important to be able to root paperbark maple in high percentages. The objective of this study was to use stock plant shading, in a commercial setting, to increase rooting success of this hard-to-propagate species.

Enhancement of Undergraduate Education in Plants, Propagation, and Production Using Regional, National, and International Tours

Author: Robert E. McNiel, Winston C. Dunwell

PP: 614

Education of undergraduate majors in horticulture can be enhanced by touring the industry related to their profession. Classroom activities of textbook, lecture, and lab are limited activities when it comes to opening the eyes of a new student to the profession. The plant material classes are limited to covering 200 to 300 plants per semester and may be limited to a single specimen on campus. A diverse industry works with thousands of plants and each plant has its own personality at each stage of life and season of the year. Textbooks in a way may be limited to the basics. At best, texts are revised on a 5- to 10-year basis. How do students keep abreast of the current technologies and changes? Labs can continue to expand the knowledge put forth in the lecture. However, equipment and plants may be the limiting factors in developing laboratory activities which would cover the breadth of this industry. Local tours during labs may be limited to a single day or a single firm. Texts,
Rooting Rhododendron Without Mist: Subirrigation and Medium pH

Author: Thomas Holt, Brian Maynard, William Johnson

PP: 618

INTRODUCTION

Mist systems have been widely used in the rooting of cuttings. They enable propagators to root cuttings with both ease and flexibility. However, mist is not without its problems. Some of these problems include leaf chlorosis, nutrient leaching, salt build-up, leaf rot, algal growth, water quality, clogging of nozzles, and other maintenance tasks. A method of rooting cuttings using subirrigation instead of mist was reported by Zhang and Graves (1995). It was recently reported that rhododendrons are difficult to propagate in subirrigation systems (Cuny, 1996). Tissue culture research shows that the optimum pH for root embryogenesis is between pH 4.0 to 5.0 (Smith and Krikorian, 1990). However, little research has been conducted on the effects of pH on the rooting of stem cuttings. We report on the use of a subirrigation system to root cuttings of Rhododendron ‘PJM’ without mist and to determine the role of the pH on rooting.

Propagation of Birch by Softwood Cuttings

Author: Brian Bunge

PP: 621

INTRODUCTION

Birch is one of the most commonly used trees in America's landscapes. For many years the primary propagation method was by seed. Selection for superior landscape characteristics created a need for clonal propagation. The two methods most widely used in the industry are micropropagation and softwood cuttings.

LaPorte County Nursery propagates the following birch cultivars by softwood cuttings:Betula nigra, B. nigra ‘Cully’, Heritage™ river birch, B. nigra ‘Little King’, Fox Valley™ river birch, and B. platyphylla var. japonica ‘Whitespire Sr’.

Marigold Growth Following Transplanting at Several Stages of Development

Author: K. Oakley, R.L. Geneve, S. Kester, M. Stafford

PP: 622

There are several studies investigating the relationship between plug size and subsequent growth. These studies involve large plugs (>7 cm3). Marr and Jirak (1990) showed that tomato transplant size decreased with smaller root volumes and length of time held in plugs. Total tomato fruit yield after transplanting to the field, however, was not negatively affected. In marigold, transplants with smaller root volumes had decreased height for up to 7 weeks after transplanting into the landscape (Latimer, 1991). There are no reports on the influence of the smaller plug sizes (<7 cm3) typical of bedding plant production on subsequent transplant development. The objective of this study was to examine marigold seedling growth and development after transplanting as affected by root restriction, canopy competition, and transplant shock.

In the first of these experiments marigold (Tagetes patula ‘Little Devil Flame’) was seeded into each cell of a 392-count plug trays (4 cm3 per cell). Twelve

Commercial Micropropagation Laboratories in the United States

Author: Richard H. Zimmerman

PP: 623

To determine the current status of commercial micropropagation in the U.S., an extensive survey of laboratories was made in March and April, 1996, by doing telephone interviews with the manager or owner of each laboratory. All laboratories contacted and currently doing commercial production provided data.

Commercial micropropagation laboratories are located in at least 26 states and most are situated near important production areas of the horticultural industries that they service. Florida leads in plants produced, followed by California, Washington, and Oregon. California and Florida each have more than 15 laboratories; all other states have fewer than 10 each. Within states, the laboratories are often clustered in certain areas. In Florida, the heaviest concentration is near Apopka, where much of the foliage plant production is located. California labs are clustered mainly in coastal areas near San Francisco, Los Angeles, and San Diego. The Pacific Northwest labs of Washington and

The Effect of Transplanting Date on the Growth of Three Evergreen Shrubs in Containers

Author: James R. Johnson

PP: 626

INTRODUCTION

Producers of woody plant material have consistently worked toward finishing stock in the shortest possible time while maintaining high quality. In the South Jersey area, container growers have noted the combination of a large vigorous liner, early transplanting date, and high fertility contribute to the profitable production of such stock.

Appleton and Whitcomb (1983) indicated that an early transplanting date has a positive effect on the growth of deciduous tree seedlings, but it was less important on evergreen tree seedlings as suggested by Whitcomb, et al.(1977).

This study was conducted to determine the effect on growth over five transplant dates.

Getting the Most Out of Growing Media and Nutrition

Author: David Nichols, Craig Godham

PP: 102

INTRODUCTION

Plants need carbon dioxide, water, mineral nutrients, oxygen in their root zone, and energy. In their natural state they acquire these for themselves. It ought not to be too difficult to help them along in a nursery, but somehow it often is. The typical Australian nursery is placed at various levels, somewhere between the maligned backyarder who recognises the simplicity of it all and the idealism of a Dutch grower nurturing a single variety with almost total environment control.

We can abridge the requirements of plant survival in nurseries into the following parts: the plant, the growing media, nutrition, the environment, pest, disease and weed control, and management.

Propagating Sassafras albidum from Root Shoots

Author: R. Wayne Mezitt

PP: 630

Sassafras albidum is an attractive native tree in the Northeastern U.S. not commonly available in the trade. It can be trained to a single stem, often forming thickets when growing in the wild. While it can be propagated both from seed and cuttings, we have found this root-shoot method simple and efficient, as well as effective in clonal production of selected individuals.

When an established sassafras thicket is cut down and mowed, shoots continue to come up in profusion for many years from the dense root system. Gently tugging on the 6- to 10-in.-long shoots in June separates them from their roots. At the bottom of the shoot is a white to pink area of the stem from which new roots have proven to generate quickly, given the proper conditions. This rooted "cutting", transplanted to a container, rapidly grows to become a uniform, vigorous, 2-ft-tall plant within about 3 years.

We dip the bottom inch of the just-pulled shoot in a 1:20 (v/v) solution of Dip 'n Gro and water for about 5 sec.

Camellia Propagation and Production

Author: Steven T. Sawada

PP: 635

INTRODUCTION

Camellias are relatively easy to propagate and to grow. At Overlook Nurseries camellia cultivars of C. japonica, C. sasanqua, C. ×hiemalis, and selected hybrids are propagated and grown in containers. The rate of growth of camellias compared to hollies and azaleas is slower, but the majestic beauty and grandeur of its flowers more than compensate for their slower growth rate.

Heat-Tolerant Perennials

Author: Bill Hall

PP: 639

INTRODUCTION

Carolina Nurseries has been producing container-grown nursery stock since Sept. 1984. At that time, most of the plant materials we grew were woody ornamentals. This included cultivars of azaleas, camellias, holly, and junipers found at most Southern U.S. nurseries. The one perennial item that we listed in our first sales catalog was Hemerocallis ‘Aztec Gold’.

As one looks through our Fall 1996 Sales Catalog, it is evident that our product mix has changed considerably—particularly in regard to perennials. Perennials now make up 13% of our annual sales. Our current catalog lists over 400 cultivars of perennials.

Improving Production Efficiency

Author: Jeff Howell

PP: 645

INTRODUCTION

Whenever you hear the word "efficiency", several things usually come to mind. Speed, automation, labor-saving, step-saving, time-saving, and money-saving are all common terms associated with efficiency. Unfortunately, the day of the push-button nursery is not yet here. However, there are probably some things that all of us can do to become more streamlined (another efficiency buzzword there).

Certainly the development of better chemicals has made all of us more efficient growers of nursery stock. Nurserymen of generations past could never have imagined the pre-emergent herbicides and slow-release fertilizers we now find commonplace. Although this is not an economics course, the biggest reason for the painfully slow rise in plant prices over the last two decades is that we have the ability to produce plants so much more efficiently than our predecessors did. But, there is still room for improvement, and it will come.

Relocation of 100-Year-Old Dogwood — Cooperation Between Public and Private Entities

Author: J. Harvey Cotton Jr

PP: 648

INTRODUCTION

This is a story about the physical act and skill required to move a massive one hundred year old dogwood out of season. The successive transplanting of this specimen dogwood was the result of the cooperation and collaboration between several public and private entities. Equally important was the tremendous public relations that was generated from the effort which greatly benefited the nursery industry and the Huntsville Botanical Garden.

Sanitation and Disease Control in the Propagation Area

Author: Russell Blackwell

PP: 651

INTRODUCTION

Many disease problems that occur in propagation are due to poor sanitation management. This results in increased diseases and a reduction in plant quality. Once a pathogen has penetrated into cutting, it is generally not economically feasible to exterminate it with chemical treatments. Hence, proper management of a sanitation program is an essential part of disease control.

Tree Seedling Production

Author: Susan Smith

PP: 654

Seed Pretreatment. Of the approximate 70 taxa oftrees we grow, 80% are started from seed. Seventy-five percent of the seed we propagate requires some form of stratification. A few varieties must be scarified before their stratification. We use warm moist, cold, and cold moist types of treatment for varying time periods—from 30 days to 6 months. Those seeds requiring warm-moist or cold-moist stratification are placed on newspaper and dusted lightly with the fungicide—Thiram WP, and agricultural streptomycin, Agri-Strep, for bacterial control. The seeds are then placed loosely in a fabric netting and packed in a bag containing damp sphagnum moss. We use the netting to eliminate the need to search for loose seeds when it is time to plant. The bags are then labeled and placed either in the office for warm stratification or the cool room for cold stratification.

Seed Propagation Houses, Trays, Containers, and Media. All our propagation houses have ground covers on the floor for weed control

How pH affects Pesticide Effectiveness

Author: David H. Tatum

PP: 657

HYDROLYSIS OF PESTICIDES

Many commonly used organophosphate and carbamate pesticides are known to degrade rapidly under mildly alkaline conditions as are found in some natural waters throughout the U.S. Buffering adjuvants can extend the effective life of alkaline-sensitive chemicals when properly mixed in the spray tank at time of spraying. Alkaline hydrolysis, the breakdown of chemicals due to the high pH of the water carrier, is one of the leading problems in obtaining effective pesticide control. The amount of acidity or alkalinity (pH) of the spray water can greatly influence how pesticides and other products perform in the spray tank. The pH of most well and stream waters fall within the range of 4 to 9. Most waters are slightly basic because of the presence of dissolved carbonate and bicarbonate salts. Alkaline hydrolysis may also occur—clogging sprayer nozzles, causing plant phytotoxicity, and/or poor pesticide control.

The breakdown or hydrolysis of pesticides is measured in

Propagating Woody Ornamentals With Bottom Heat

Author: Bob Black

PP: 660

INTRODUCTION

Bennett's Creek Nursery is located in the southeastern corner of Virginia. During the cooler months our climate requires supplemental heat to maintain 21C (70F) root zone temperatures. This paper will describe our recently installed heating system. Crops produced, propagation technique, and overall benefits of the system are discussed.

Weed Management Strategies for Container Production

Author: Charles H. Gilliam

PP: 663

INTRODUCTION

Weed control in the production of container-grown landscape crops is essential if the plants are to be successfully marketed. Container nurseries provide an optimal environment for weed growth with frequent overhead irrigation and fertilizer applications necessary for maximum growth of landscape plants. Weeds in container-grown plants are unsightly, reduce growth of the landscape plant, and contribute to the spread of weeds into the landscape. As a result, weed control strategies are an important component in the overall production of container nursery crops. In this paper, I will attempt to address some of the common questions related to weed control in containers.

Effect of Saline Irrigation Water on the Production of Nursery Crops on Capillary Sand Beds

Author: Gail E. Barth, Kevin A. Handreck

PP: 105

Data on the effects of saline water on the production of nursery stock on capillary beds are presented. Growth comparisons are made between over-head irrigation and capillary bed irrigation in a range of saline sensitive and tolerant crops. Results from salinity trials where plants were irrigated with water up to EC 3.0 dS m-1 are presented. Leaching of excess salts and mulching treatments are shown to be effective as management tools for handling salt build-up in pots. Control of root emergence from pots onto the capillary beds can be achieved with dichlorophen.
A New Approach to Irrigation

Author: Tom Saunders

PP: 667

INTRODUCTION

I am changing the title of my talk from a "High Tech Irrigation" to "A New Approach To Irrigation." For those of you who don't know me, I am the production manager of Saunders Bros., Inc., Piney River, Virginia. I have worked in this capacity for the past 15 years, since graduating from Virginia Tech University in the field of ornamental horticulture. Piney River is nestled in the scenic Blue Ridge Mountains in central Virginia between the cities of Lynchburg and Charlottesville. It was the final touchdown site of Hurricane Camille in 1969. Camille (a category 5 hurricane) killed 125 individuals in our county when rainfall fell at a rate believed to be unmatched in recorded history. Rainfall was in excess of 76 cm (30 in.) during a 6-h period. Meteorologists reported approximately 630 million tons of water falling over the county's 471 miles, which would have the energy value equivalent of a 40,000 megaton nuclear bomb. Incidentally, it was this natural disaster which

Horticultural Opportunities

Author: David Ellis

PP: 676

INTRODUCTION

There are numerous production opportunities in the nursery industry. Some opportunities for producing nursery crops include: specialty floriculture items, specialty nurseries, mitigation and restoration, specialized propagation nurseries for seed production and rooted liners, and site preservation.

Specialty Floriculture. This includes — fresh, dried or preserved foliage, flowers, twigs, branches, or seed pods. It is difficult to develop a new business in this industry since established companies are quite protective of their interests. At trade shows company booths may be walled-off and it is understood that competitors enter only on invitation.

Herein is where the opportunity lies. A grower of floral materials has the options of selling to the local retail market, or selling larger quantities to the wholesale market at reduced prices. Growers have confided in me that they can grow these products, but that there is no market for them. I suggest the formation of a nationwide

The Internet and How It Applies to the Nursery Industry

Author: Bill O'Meara

PP: 678

THE WEB

The backbone of the world wide WEB is the Web Page which is constructed using hypertext markup language (HTML). The words, graphics, and sound that are transmitted on the WEB is defined using HTML. One of the keys in making this easy to use is the ability of the user to move from one page to another by "pointing and clicking" with the computer cursor. This hypertext link allows the user to move from one document to another without knowing where that next document resides. Therefore, a user could be reading a growers catalogue written by a nursery in Oregon and reference an article on Plant Trial Tests published by the Auburn University in Alabama. The illustration below is the home page for the BoShanCee Nursery WEB site. Presently, our site contains nine pages of text. We have taken 35 mm pictures of our plant material for sale this season and are adding them to our site so that our customers can see a picture of the plant they are considering purchasing.

Adventitious Rooting of Stem Cuttings of Loblolly Pine as Influenced by Carbohydrate and Mineral Nutrient Content of Hedged Stock Plants

Author: D. Bradley Rowe, Frank A. Blazich, Farrell C. Wise

PP: 682

Hedged stock plants of four full-sib families (B, G, R, and W) of loblolly pine (Pinus taeda L.) were fertilized daily with a complete nutrient solution containing either 10, 25, 40, 55, or 70 ppm N. In May 1995 (spring softwood), July 1995 (summer softwood), and Jan. 1996 (winter hardwood) terminal stem cuttings were taken for tissue analysis and rooting studies. Spring cuttings rooted in the highest percentages (59.5%), followed by winter (40.5%), and summer (34.7%). Maximum rooting for spring (70.0%), summer (48.6%), and winter (55.6%) occurred with cuttings taken from hedges that received 55 ppm N. Winter values of total nonstructural carbohydrates (TNC) were twice levels present in spring or summer (32.8% vs. 17.1% and 16.3%), but levels remained relatively constant with increasing applied N. In contrast, average N concentrations were lower in winter (1.29% vs. 1.79% and 1.69%) and increased linearly with increasing applied N levels. Genetic differences among families were evident as families B, G, and W exhibited a quadratic response with maximum rooting of 61.1% at 70 ppm applied N, 62.4% at 55 ppm N, and 63.0% at40 ppm N, respectively. The TNC: N ratio was not correlated with rooting and an optimal TNC: N ratio for rooting success was not found. However, optimal rooting occurred at concentrations ranging from 1.8% to 2.0% N for spring and summer softwood cuttings and at approximately 1.5% N for winter hardwood cuttings. Also, low tissue B concentrations, which were not detrimental for plant growth, may have severely inhibited adventitious root formation.
Sequential Benzyladenine (BA) Applications Enhance Offset Formation in Hosta

Author: James M. Garner, Gary J. Keever, D. Joseph Eakes, J. Raymond Kes

PP: 689

A study was conducted to determine the effects of repeated benzyladenine (BA) applications and subsequent repeated offset removals on offset yields from hosta stock plants. Two hosta cultivars, ‘Francee’ and ‘Frances Williams’, received either 0, 1, 2, 3, or 4 foliar applications of 3000 ppm BA. Plants receiving multiple applications were retreated at 30-day intervals following offset removal from all plants. BA application stimulated offset formation in both cultivars, but repeated applications were necessary for a continued response following offset removal. Offset removal did not inhibit a subsequent response to BA, and total offset yield increased with an increasing number of BA applications. Over the 120-day study, plants of ‘Francee’ receiving four applications formed 124% more offsets than controls, while plants of ‘Frances Williams’ receiving four applications formed an average of 18 offsets over the 120-day study, compared to none for controls.
Azaleas For the 21st Century

Author: Maarten Van Der Giessen

PP: 693

INTRODUCTION

When my father and I began our liner nursery in 1990, we produced a broad line of woody ornamentals and azaleas in 7.6-cm (3-in.) pots and rooted cuttings. As our business developed, we began to look for market alternatives to the general ornamental line. We began our search with the question of "What can we produce in this area which would fill a unique, marketable need in the industry?" Since Mobile County, Alabama produces more azaleas per square mile than anywhere in the United States, azaleas seemed like a reasonable starting point to look for an answer.

Quickly we found that we were dealing with a plant group which have been actively hybridized for the past fifty years with few commercial outlets in the market. While the wholesale industry at large was producing greater and greater quantities of azaleas, backyard enthusiasts were producing better and better quality plants. Typically, these new azaleas were traded among enthusiasts or released to specialty growers

Dogwood Propagation from Cuttings

Author: Bob Byrnes

PP: 697

Trail Ridge Nursery is located in northeast Florida, halfway between Gainesville and Jacksonville and about 50 miles south of the Florida-Georgia state line. We are on the southern edge of USDA Hardiness Zone 8b. We are a wholesale container tree nursery specializing in cultivar trees with an emphasis on flowering dogwood (Cornus florida) and southern and oriental magnolias (Magnolia spp.).

We initially grew our flowering dogwood from seed. However, we realized that seed propagation did not produce a uniform crop. We were ending up with a large number of unacceptable trees and the good trees would not flower for several years, if at all. We then decided to put our efforts into growing named cultivars only.

In evaluating several named dogwood cultivars, we found that most did not grow well for us. We felt that it was probably because they were selections from areas farther north and not well adapted to our area. We did, however, have one white-flowering form that was a much

Variations in pH from Different Bark Sources

Author: Allen D. Owings

PP: 699

Management of medium pH is an important consideration in commercial production of nursery crops. Bark source, fertilizer source, and dolomitic lime application rate are significant factors in pH management, while dolomitic lime source is not significant. Plant growth is influenced depending upon timing of fertilization and optimum pH for the species being grown.
Short History of the International Plant Propagators' Society

Author: Jo Dawkins

PP: 705

History is important — what has happened in the past can guide us in the future.

I.P.P.S. is based on the sharing of ideas and experiences that can help us all in our work in the future.

Mr. Jim Wells of New Jersey, U.S.A. was responsible for the early development of I.P.P.S. Jim, now 82, was the first President and it was his enthusiasm that saw new Regions develop in England, New Zealand, and Australia.

1951.The first meeting of the Plant Propagators' Society was held in Cleveland, Ohio, U.S.A. About 80 people attended and a number of interesting papers were presented, including the first written paper on rhododendron propagation. Rules and guidelines were set down—many are still with us today. The most important is not "where you work or where you come from; it is you the propagator who is important. It is what you do, what your knowledge is, and how much you are willing to share your knowledge that counts". The motto is important, "Seek and Share". We can all learn from and share with

Vegetative Propagation of Apricot (Prunus armeniaca L.) by Softwood Cuttings

Author: Y. Murai, H. Harada, R. Mochioka

PP: 706

Apricot (Prunus armeniaca L.) cultivars were propagated by softwood cuttings in order to evaluate rooting ability. ‘Heiwa’ cuttings with IBA (indolebutyric acid) treatment inserted in June gave the highest rooting rate, while rooting did not occur in August or later. ‘Heiwa’ cuttings without IBA treatment did not root, regardless of the timing of cutting collection. Optimal IBA treatment for rooting of ‘Heiwa’ was investigated. The highest rooting rate and the largest number of roots per rooted cutting were obtained when the cuttings were soaked in 80 ppm IBA solution for 20 h. Cultivar difference in rooting ability was evaluated using five cultivars. Rooting rate varied from 63.3% for ‘Shinshuohmi’ to 96.7% for ‘Alfred’. Larger numbers of roots were associated with the cultivars that had the higher rooting rates.
Deciduous Ornamental Trees in Australia

Author: Wesley J. Fleming, Liz Darmody

PP: 111

Public demand for, and therefore the importation of, deciduous ornamental trees is ever-increasing. This influx has the potential to greatly enhance our environment. As professional horticulturalists and home gardeners alike, we realise the advantages that these trees offer as landscape subjects.

There are many outstanding ornamental cultivars now available in Australia. The Acer (maple), Cornus (dogwood), Tilia (linden), Lagerstroemia (crape myrtle), and ornamental Pyrus (pear) are afew species which we believe havepotential, but these represent only a sample of what is currently available.

Consideration must be give to a whole range of criteria before a species or cultivar is selected for planting, e.g. the existence of underground sewerage; height, colour and design of surrounding buildings; power lines and other overhead obstructions; narrow streets; soil type; drainage; and aspect. People tend to place a high emphasis on what the site looks like when a tree is first planted.

Vegetative Propagation of Japanese Plum (Prunus salicina Lindl.) by Softwood Cuttings

Author: H. Harada, Y. Murai

PP: 710

Seasonal changes in rooting ability, effect of IBA treatment, and cultivar difference in rooting ability of softwood cuttings of Japanese plum cultivars were investigated. When treated with IBA, the cuttings stuck in June gave the highest rooting rate. The rooting rate gradually decreased and plants did not root in September. Without IBA treatment, the highest rooting rate was obtained in May and rooting did not occur later than July. Soaking the basal portions of the cuttings in 20 or 80 ppm IBA solution for 20 h and dipping the basal portions of the cuttings into 4000 ppm IBA solution for 10 sec gave similar rooting rates. The number of roots per rooted cutting was greater with the IBA treatment at 20 or 80 ppm than the 4000 ppm dipping treatment. There was a great variability in the rooting ability among Japanese plum cultivars. Rooting rates varied from 24% for ‘King’ to 100% for ‘Methley’.
The Commercial Production of Japanese Persimmon ‘Fuyu’ (Diospyros kaki ‘Fuyu’)

Author: Y.Ohta

PP: 714

A HISTORY OF THE PRODUCTION OF FUYU-GAKI.

The First Stage (-1963). During this stage a cold-store was established, and a start was made on a specialized 3-ha orchard of kaki (Diospyros kaki).

The Second Stage (1964–1971). During this stage, part-time workers were employed and in order to provide a longer period of employment for the staff, the production farm was doubled in size (6 ha). Production and management staff took over the day to day running of the farms whilst production was increased through our technical direction.

The Third Stage (1972–1980). This period saw the establishment of a sales strategy for kaki and a new cultivation system. The Marukin-Seika Co. was founded in 1978 (initial capital: 10 million yen). By means of strict quality control and reliable supply our brand became established in the market.

The Fourth Stage (1981–1990). This stage saw the expansion of storage facilities with five new cold-stores (total 825 m2 ) added and expanding sales. Two lines of

Cultivars and Breeding of Gloriosa

Author: H. Yamamoto

PP: 715

Gloriosa is a bulbous climber of the Liliaceae that grows wild in tropical regions and Africa. Recently, cut flowers and potted plant have become commercially available in Japan. Over 10 cultivars including one major cultivar, G. superba ‘Rothschildiana’, are grown. The following are cultivars that are grown in Japan. The characteristics of each cultivar are briefly described below.
Horticultural Improvement of the Native Azalea, Rhododendron tosaense

Author: S. Yamaguchi

PP: 717

INTRODUCTION

Japan has many native azaleas scattered throughout the country, and people have appreciated their beautiful flowers since ancient times. In the Edo era, people were especially keen about horticultural plants, such as azalea, chrysanthemum, camellia, primrose, hydrangea, gardenia, dianthus, flowering cherry, mume, willow, etc. With regard to azaleas, several groups, such as Kurume, Satsuki, Hirado, and Miyama, were developed from the native species on Kyushu Island. They were taken to western countries and bred to produce many horticultural evergreen azaleas, such as Belgian forcing azalea, Glendale, etc.

I would like to introduce one promising native azalea, Rhododendron tosaense, ‘Fuji-Tsutsuji’ (meaning mauve-coloured azalea) from Shikoku Island.

Care of Stock Plants and Cutting Production of Kalanchoe

Author: N. Oida

PP: 718

MAINTENANCE OF STOCK PLANTS

The practical life of a kalanchoe stock plant is usually 1 year. To obtain suitable cutting material, the stock plant is potted on three times in the course of a year. As it grows taller the stock plant becomes unstable and falls over easily so it needs frequent thinning. The maintenance of the stock plant is very important, but is labour-intensive.

I learned about the container culture of kalanchoe stock plants in Denmark, and applied a modified version of this technique to my present cultivation system. A styrol box (70 cm × 43 cm × 14 cm) equipped with four watering wicks at the bottom was used for the cultivation of the stock plants. Eight to ten stock plants were planted in this box with a kalanchoe compost [unconditioned peat, conditioned peat, perlite, manure (6: 7: 4: 3, by volume) pH 5.5–6.0, EC 1.2 mmhol. On average, five to six cuttings were harvested from each stock plant per month. In winter, the number of harvestable cuttings decreased. In

Controlling Root Systems with Slit Containers

Author: S. Watanabe, M. Nakamura

PP: 719

In the container production of many horticultural plants, root circling is a serious problem. It is specially important in the production of large trees to prevent root circling as it has a deleterious effect on the growth after planting out. In many nurseries, however, trees are often grown without any treatment to prevent root circling. As a result, root distortion and aging can be observed at an early stage of growth. In addition, street trees with weak root systems are uprooted easily by strong winds such as typhoons. Therefore, we investigated the combination of soil media in the container, the amount of watering, and the material and structure of the container in order to avoid root circling.

The soil medium used in the experiment was mainly composed of a mixture of red earth or weathered granite as the basal medium and peat moss. The mixture was adjusted by adding kanumatsuchi, hyugatsuchi, perlite, and charcoal to improve the physical condition of the medium. Attention was paid

Production of Large Evergreen Landscape Trees and Their Typhoon Protection in the Nursery

Author: S. Kinoshita

PP: 721

INTRODUCTION

Even though the economic bubble has burst in Japan, the price of land is still extremely high in the cities. There is a trend toward the planting of large landscape trees around new commercial buildings as a status symbol. Urban renewal is also taking place in large cities from Osaka to Tokyo.

These large buildings affect the microclimate of the surrounding area. To soften the effects of these changes, various regulations have been adopted to control spacing, and landscaping of buildings to blend with their surroundings. Along with the increase in land values, large-grade landscaping trees are in demand by the owners of large buildings.

In order to meet these demands, my company is run with the following points in mind.

Seedling Propagation of Sophora microphylla

Author: Robert Appleton

PP: 723

INTRODUCTION

The planting of indigenous tree species is continuing to increase and public interest in their use is in three broad categories:

  1. Home gardens
  2. Landscaping of recreational areas, riparian zones, and highway plantings
  3. Regeneration of native forests

Seedling propagation of New Zealand indigenous plants is a common form of propagation for a number of reasons.

  1. Where seed is readily available, large numbers can be grown economically
  2. Root systems are superior to cutting-grown plants and can result in more successful establishment
  3. Seed can be stored for long periods of time owing to the very bard seed coat
  4. Genetic diversity through cross pollination is insured, very important when propagating small and isolated populations
Miniature Rose Production in Gifu Prefecture

Author: Y. Yotan

PP: 726

Our company, Bromellia-Gifu Ltd., situated in the towns of Yoro and Kaizu in the warmer southern region of Gifu Prefecture, was founded in 1990 by a group of growers for the production of bromeliads. Initially the company concentrated on growing bromeliads, however, in 1992, miniature rose production began.
Rose Production in the Present and Future

Author: K. Tsujita

PP: 727

INTRODUCTION

Gifu Prefecture is home to the largest area of rose production in Japan. In this paper I will report on the present and future problems of rose production.

Crape Myrtle Propagation

Author: Don Covan

PP: 112

Lagerstroemia indica (crape myrtle) has been a popular deciduous flowering shrub or small tree in the Southern United States since its introduction from Asia more than 150 years ago. Crape myrtle's popularity has steadily increased, but took a huge leap when Dr. Donald R. Egolf of the United States National Arboretum began releasing new hybrid cultivars. By crossing L. fauriei (a small tree from Japan) with L. indica, Dr. Egolf produced hybrid cultivars with features which truly make them "a plant for all seasons".

Egolf's new cultivars display several wonderful characteristics throughout the year. In early spring their new leaves are often bronze or garnet tinged. In summer their blossoms are spectacular—sometimes continuing to bloom from late spring until late autumn. Their vibrant autumn foliage ranges in color from yellow to vivid oranges, and reds. As fall changes to winter the beautiful exfoliating bark can be observed, which reveals color extremes from cream to red-brown. This colouration remains vivid throughout the winter months.

Cut-flower Production of Roses in Goudo

Author: Y. Takada

PP: 728

The decision of several cucumber farmers to change to rose cultivation in 1970 saw the start of cutflower production of roses in Goudo. Seven years later, the agricultural corporation, Rose Production Corporation of Goudo, was founded. In 1984, the rose was registered as the town flower of Goudo. Since then, rose production has been regionally promoted in Goudo. From 1986, direct sales to consumers by means of a house-to-house delivery system began with large sales made for Mother's Day and Father's Day.

ORGANIZATION (IN 1993)

  • No. of farmers; 11 families
  • Total cultivated area: 493 acres
  • Yield: 5,240,000 sterms.
  • Production: ¥500,000,000

METHODS OF CULTIVATION

  • Thorough disinfection before planting
  • Sufficient fertiliser
  • Ripping subsoil to the depth at 1.0 m before planting
  • Adoption of rockwool culture to achieve best use of labour and uniform results
Orchids in Thailand

Author: C. Itthisak

PP: 729

"A country of smiles" is the frequently used catch-phrase in guide books and pamphlets introducing Thailand.

In Thailand, the average temperature is 28C, there is abundant sunshine every day, and a plentiful supply of tropical fruits.

Because the Thai economy is increasing by 8% every year, Bangkok (Krung Thep), its capital, is a hive of construction of large skyscrapers and condominiums. Along with a rapid increase in population has come a number of environmental problems including world famous traffic congestion which produces dust and exhaust fumes that destroy the sweet tropical atmosphere.

Even in such a busy dusty city in the rainy season, they have heavy squalls in the afternoons, the city becomes calm. The time passes slowly like the Menam river (Chao Phraya) and people wait patiently until the rain stops. Thai people are patient by nature and visitors to Thailand should relax and appreciate the spirit of the Thai people.

At present, Thailand is facing a dangerous ecological

Effects of Media and Time of Seed Collection on Seed Germination of Cypripedium macranthum var. rebunense

Author: M. Tomita

PP: 730

To obtain basic information for maximizing the in vitro seed germination of Cypripedium macranthum var. rebunense the suitability of media and the optimum time of seed collection were investigated. Seed capsules were collected at weekly intervals ranging from 5 to 8 weeks after pollination and inoculated on four tested media (Harvais, ½ MS, ½ Norstog, and T). Seeds collected at 6 weeks after pollination had the highest germination regardless of the medium components. Germinations and subsequent growth on both °Norstog and T medium were better than those on Harvais and ° MS medium. Eighty weeks after inoculation, seedlings were transplanted to soil-based media, and a preliminary investigation was made of the relation of cold treatment to sprouting (shoot elongation).
Sales Strategy for Cactus

Author: K. Kato

PP: 735

Thirty years have passed since the start of our retail cactus growing business. Such direct sales are limited with little chance to increase the business. Later we tried sending plants to the auction market. At the auction, we received prices equal to those from direct sales, and this changed the direction of our marketing in favour of the auction.

Production of cactus had to be increased which caused several problems, such as the difficulty of flower forcing, the spilling of sand-compost during transport, and other problems. A new product, "petit-cactus", targeted towards young girls as consumers, was introduced in 1983. They were decorated with small dry flowers and with sand solidified with special paste to prevent spillage. This unique product became a big hit, and set a record by selling a million units in 3 months. It will be difficult for anyone to break this record in the future.

At present, 80% of our business goes to the auction market and 20% to other outlets. These other

Effects of Cytokinins on Multiplication and Rooting of Micropropagated Shoots of Spathiphyllum

Author: W. Amaki, M. Mamuro, H. Higuchi

PP: 736

Using micropropagated shoots of Spathiphyllum, the effects of cytokinins, including new types which were recently introduced into micropropagation, on shoot multiplication and rooting of multiplicated shoots were examined. Phenylurea-type cytokinins (CPPU and thidiazuron) markedly promoted shoot multiplication and inhibited rooting of multiplied shoots at more than 0.1 mg liter-1. A water soluble BA (TG-19) showed a promotive effect on shoot multiplication similar to BA. The results showed that BA was the most effective cytokinin for micropropagation of Spathiphyllum.
Inducing Callus Formation from Leaf or Petiole Segments and Culture of Callus in Pelargonium

Author: S. Yasugi, Y. Mochiyama

PP: 743

INTRODUCTION

Pelargonium is an important source of perfume because of its strong fragrance.

The purpose of this study is to induce callus from the leaf or petiole segments of two taxa of Pelargonium, to examine the difference between the two taxa in the induction of callus, and to investigate the proliferation rate of callus during subculture.

Growth Characteristics of Nursery Plants Regenerated Through in vitro Culture in Leek (Allium porrum L.)

Author: T. Kanazawa, M. Hatakeyama, K. Sato, H.M. Xue, T. Harada, T. Yak

PP: 744

The growth characteristics of leek (Allium porrum L.), regenerated through in vitro culture, were investigated. Leaf sprouts emerged from the ground 2 to 4 weeks after planting in the field. Adult foliage followed, and four to five leaves were produced by December. The following April the foliage began to elongate and the plant height increased. By July the leaves had completely expanded and bolting and flowering followed. The number of bulbs per plant at harvest was 6.2 in the control. However, they varied from 2.9 to 9.7 among the 29 lines under investigation. The fresh weight of bulbs per plant also ranged from 3.8 to 25.3 g. The relationship of the fresh weight of the bulbs between planting in 1995 and harvesting in 1996 was shown to be significantly positive (r = 0.86) and was also consistently stable. These results provide significant information on growth characteristics of plants regenerated through in vitro culture, and indicate that an individual selection by numbers and fresh weight of bulbs as an index, will increase the efficiency of cultivation.
In vitro Inoculation Test for Resistance to Crown Gall Disease on Roses

Author: L. Zhou, H. Fukui, S. Matsumoto

PP: 750

Rosa ‘Fashion Parade’, R. canina, R. canina ‘Superbe’, R. ‘Pekcougel’, Anna® hybrid tea rose, and R. ‘Meihartfo’, Kalinca® floribunda rose (syn. R. ‘Pink Wonder’) were cultured by shoot tip culture and were micropropagated every 6 weeks in vitro. Agrobacterium tumefaciens was isolated from crown gall collected from a rose plant. The shoots inoculated with A. tumefaciens formed white or white-green crown galls. Four methods were used for inoculation: (1) needle prick inoculation (needle), (2) spread inoculation at upper end of shoot (upper), (3) spread inoculation at lower end of shoot (lower), (4) slice off bark and inoculate (slice). Shoot growth was not affected by inoculation of A. tumefaciens except for slice. Four weeks after needle inoculation, the rate of shoots which formed crown gall rose to 70% and remained stable. Therefore, the needle prick inoculation was the most successful and easiest to administer.

Five roses: R. ‘Fashion Parade’, R. canina, R. canina ‘Superbe’, R. ‘Pekcougel’, Anna® hybrid tea rose, and R. ‘Meihartfo’, Kalinca® floribunda rose were inoculated by the needle method. Rosa canina and ‘Fashion Parade’ had no resistance to infection and disease. Rosa canina ‘Superbe’ was resistant to infection but lacked resistance to disease. Rosa ‘Pekcougel’, Anna® hybrid tea rose, and R. ‘Meihartfo’, Kalinca® floribunda rose (syn. R. ‘Pink Wonder’) were not infected and resisted disease infection.

The Effect of CCC and BA on the Formation of Potato (Solanum tuberosum L.) Microtubers

Author: T. Yamamoto, K. Nakata

PP: 755

Microtubers formed in vitro—which are usually in the range of 7 to 10 mm in diameter—should be a useful size for the convenient storage, long distance transport and circulation of elite clones. To date, many studies have reported on the promotive effects of cytokinins and growth retardants on the formation of microtubers. In the present experiment, using the micropropagated shoots of potatoes originated from meristem culture, we investigated the mode of formation of microtubers on solid medium and the effects of CCC (chlorocholine chloride) and BA (benzyladenine) on the formation of microtubers. Two types of in vitro tuberization were observed in dark conditions. One was a sessile microtuber, formed from axillary buds on the shoot, which occurred in an early stage of culture, and the other was a microtuber formed on a stolon arising from the shoot. The external morphology of a small organ transforming into a tuber from an axillary bud after two days of culture was observed by scanning
Acclimatization of Bulbous Plants Between Northern and Southern Hemispheres

Author: T.E. Welsh, M. Saito

PP: 756

During the last decade international transportation of goods has become fast, frequent, and reliable thanks to growth in the airline industry. This has created a worldwide trade in perishable floral products. These products include cutflowers, live plants, and flower bulbs. The term "flower bulb" includes bulbs, tubers, rhizomes, corms, and offsets. These plant modifications which provide food storage for survival during a resting period, create an ideal item for exporting to overseas countries. Millions of bulbs are transported between countries such as Holland and Japan with little difficulty in acclimatisation. Shipping bulbs from the Southern Hemisphere to the Northern Hemisphere creates some problems but also some opportunities.

When considering importing bulbs from the Southern Hemisphere, the environmental conditions that bring on dormancy and break dormancy must be studied. An understanding of flower induction is also necessary to get a controlled result. Bulbs can be put in the

Breeding Approaches to the Development of Selected Australian Native Daisies for Pot Culture

Author: Alexander Salmon

PP: 47

INTRODUCTION

In the period 1990–94 Plant Growers Australia P/L conducted an extensive breeding program aimed at improving members of the Australian Asteraceae (daisies) for commercial pot culture. The specific aim was to develop novel and proprietary cultivars for markets in the northern hemisphere where a number of Australian daisy species had already achieved considerable success. Since commencement, over a dozen new cultivars have been commercialised and many are protected in this country by plant breeders rights. Cultivars derived from the project are now cultivated in Europe, North America, New Zealand, and Japan. This paper summarises the approaches adopted, both successful and otherwise, to improve this diverse flora. The aim is to provide some guidelines for horticulturalists wishing to pursue a program of plant improvement by breeding, and has particular reference to other Australian taxa which are yet to realise their full commercial potential.

Propagating Herbaceous Perennial Liners and Plugs

Author: David J. Beattie

PP: 114

INTRODUCTION

Herbaceous perennials or most often just called perennials are frequently planted in private and public gardens, and in the promotional gardens of landscape designers or growers. Perennials provide a unifying design influence between woody plants and annuals. They are even being used to beautify highway rest stops; I recently saw thousands of Hemerocallis ‘Stella de Oro’, the most popular daylily in the U.S.A., planted at a truck stop in Virginia.

In the past, perennials were often field-grown, dug, and sold directly to the consumer. Although field production of perennials continues to expand, container production has increased dramatically. Containerized plants are more marketable. In addition, this production method allows considerable mechanization, facilitates shipping, and circumvents several transplanting problems. Containerization has also resulted in a marked increase in the propagation of smaller plant sizes—liners and plugs—which can be easily produced by

Ornamental Climbing Plants at the University of British Columbia Botanical Garden

Author: Bruce Macdonald

PP: 758

INTRODUCTION

The University of British Columbia Botanical Garden is the oldest university botanical garden in Canada. It was established in 1916 under the Department of Biology and was essentially a teaching garden, but at the same time served an important role in the beautification of the new campus. In 1968 the university's board of governors designated a new 70-acre site for the construction of a new botanical garden. The challenge to design and develop this project was taken up by the Garden's former director, Dr. Roy L. Taylor.

Today the Garden has over 14,000 accessions, some 10,000 different plants and plays a major role in education and research, as well as in developing close ties with the community and the professional horticultural industry.

Cultivar Integrity in Australian Tree Production

Author: James Will

PP: 117

In Australian tree production, many of the issues concerned with producing high quality trees have been addressed. Root system research has lead to the production of trees that successfully establish post-transplanting. Also, tree cultivars of non-Australian origin are quickly imported by the major propagating companies, and are made available to the market for testing and sales, once quarantine requirements are met. This leaves three areas of deficiency in Australian tree production:
  1. Formative pruning and the development of tree canopies to best suit the end use.
  2. Trialing of taxa to ascertain their suitability for differing Australian landscape situations.
  3. Making certain that the cultivars we are using are the cultivar they purport to be. With trees, it is especially important that horticulturists plant know cultivars.

Estimates indicate that street trees require expenditure of approximately $10,000 over an amenity

Propagation of Wilga, Geijera parviflora

Author: Bryan Mole

PP: 122

Successful propagation of Geijera parviflora from seed and juvenile cuttings was achieved. Seed dormancy was overcome by removing the hard seed coat (testa). Both naked embryos and embryos with endosperm intact, germinated readily at 20C with a 12 h photoperiod. No seed with any part of the testa intact germinated. Naked embryos placed on crushed testa failed to germinate, indicating a chemical inhibition. Cuttings harvested from nodes 1 to 12 showed reduced rooting potential at higher nodes, with 100% strike at nodes 1 and 2 to 0% strike at node 12. Cuttings from branches between nodes 1 to 12 also showed reduced rooting potential to those from the main stem. Hypocotyl cuttings formed roots within 20 days. Hypocotyl cuttings treated with IBA 500 ppm, had a greater total root length than cuttings with no treatment. Semi-hardwood cuttings harvested from mature trees in late autumn were unsuccessful.
Marketing Australian Plants Internationally

Author: Rodger Elliot

PP: 127

WHO ARE KOALA BLOOMS?

Koala Blooms is an Australian-owned company which markets Australian plants internationally. Koala Blooms was formed in 1989 as a result of marketing research undertaken in Europe and U.S.A.

The following aspects highlighted the need for Koala Blooms to be formed:

  1. Demand existed worldwide for plants new to the horticultural industry.
  2. Australian plants had proved successful in overseas markets but foreign companies were involved, with little or no return for the Australian horticultural industry.
  3. There was no Australian company to develop and market Australian plants as export products.
  4. The international image of Australia was positive and advantageous in marketing Australian plants.
  5. There was not much cultural knowledge on Australian plants as propagation and growing protocols were not provided.

Koala Blooms was set up to provide a structure enabling Australian plants to be marketed in international markets by Australians, with benefits flowing

Plant Breeding Legislation in Europe

Author: Jørgen H. Selchau

PP: 131

INTELLECTUAL PROPERTY AND ADMINISTRATION

It seems that some people today believe that breeders, researchers, and others, who are devoted to the development of new plant varieties, be it agricultural or horticultural species, are akin to the "alchemists" of ancient times. Convinced that they are able to transform any base metal into the most precious of all: gold! Influenced by a deep belief in the mystical teachings of chemistry, the alchemists had faith that they would, eventually, reach their ultimate goal.

After more than 10 years in close contact with breeders and researchers, I have realised, that modern breeding programmes truly do include techniques and methods far beyond the "golden" eggs. Consequently it is of the utmost importance for the plant breeder to protect his invention. This paper is an attempt to inform you of the basic ideas of intellectual property legislation in Europe and the practical implementation of such systems through plant variety rights legislation.

The Diversity of British Columbian Native Plants for Nursery Production

Author: Bruce Macdonald

PP: 134

The extremes of British Columbia's climate and natural landscape are primary reasons for its diversity of native plants. British Columbia's geography encompasses alpine meadows in the mountainous regions of Revelstoke, Whistler, and Manning Park; the rainforests of the Queen Charlotte Islands and the west coast of Vancouver Island; the arid regions of the Okanagan Valley in the interior of the province; and the lower altitude areas of the Fraser Valley.

Visitors to British Columbia will soon become aware of its provincial flower—Cornus nuttallii (Pacific Coast dogwood). This deciduous tree is renowned for its large white flowers in the spring. However, it is not an easy tree to grow in the urban landscape as it does not like root disturbance and its bark splits if exposed to excessive sun. In addition, the last decade has seen an increasing incidence of anthracnose caused by the pathogen Discula sp. Dogwoods which are under stress from a long hot summer are particularly prone to

The Need for a Region of the I.P.P.S. in South Africa

Author: Rod Saunders, Rachel Saunders

PP: 137

On the 2 Feb. 1990 F.W. de Klerk, who was the president of South Africa at that time, made a momentous announcement. The African National Congress (ANC) was no longer banned as a political party. The South Africa Communist Party was free to operate without restrictions. A number of political figures who had been in jail for many years were to be released, and the way was paved for the first multi-party, multi-racial, truly democratic elections in South Africa (SA). Apartheid was at last being dismantled. With those words, South Africa stepped back from the abyss of chaos and anarchy looming before it, and re-entered the world from which it had been excluded.

For most people like ourselves, the relief was immense. We could now start taking greater control of our lives and plan our future in SA. However this posed a number of problems for SA business people. South Africans were now exposed to the full cut-throat competition of world trade. Previously SA business had been able to

Training the Plant Propagator—A Burnley College Perspective

Author: Peter May

PP: 140

Burnley College is a specialist institution providing training and education in urban/amenity horticulture. It is currently affiliated with the University of Melbourne's faculty of Agriculture, Forestry & Horticulture as part of the Victorian College of Agriculture and Horticulture. Burnley has been training students in horticulture for some 100 years. This long history, as well as our combination of higher education and TAFE (Technical and Further Education) programs gives us a perspective on horticultural education which is unusual.

In the 16 years since Burnley's programs were last discussed at an I.P.P.S. Conference (1980 Australian Region) much has altered. We now provide training beyond diploma level and have a much wider range of courses on offer. We have been offering a degree (B.App.Sci.[Hort]) since 1985 and a postgraduate research degree (M.App.Sci.[Hort]) since 1992. This provides the horticulture industry in Victoria and Australia with the opportunity of employing

Competency-Based Training—Implications for Horticultural Education

Author: Frederick C. Hellriegel

PP: 141

Competency-Based Training (CBT) can be defined as an approach to learning which places primary emphasis on what the learner can actually do in the workplace as a result of training. It is focused on the outcomes or competencies rather than on the learning processes or the time spent on these processes. This reflects a major shift away from the conventional approach to education and training.
Training Programs for the Horticulture Industry - from Research to Practice

Author: Robert Sward, Jenny Beaumont, Bernadette Swanson, Tony Slater

PP: 142

The Institute for Horticultural Development (IHD) is one of Australia's major research and development institutes supporting the horticultural industry and its allied trades. A critical part of the Institute's core business is to provide training to assist producers, processors, and product and produce managers to develop the skills and knowledge needed to adopt world competitive practices.

Continuing industry-based research and development programs within and outside the Institute provide information and technology that is at the forefront of international science. However, the information derived from current and past research is not often in a form in which can easily be adopted and integrated by industry personnel into the management practices of their workplace. A further complication is that the horticulture industry is comprised of a number of diverse sectors producing a multitude of different commodities, on farms of different types, and processing and marketing them

New Genetic Approaches to Plant Conservation

Author: Elizabeth James

PP: 51

INTRODUCTION

The horticultural and agricultural industries rely on plant genetic resources for the development of new crop varieties. Traditional breeding methods involve making new combinations of the genetic material from each parent with the aim of changing the characteristics from parent to offspring and exploiting the genetic diversity present in the parents. The diversity may include variation in flower colour or disease resistance which can be used to commercial advantage.

We have heard about the role biotechnology can play in the commercial horticulture field, and how new molecular techniques allow genetic material to be introduced in ways not possible using traditional breeding methods. I would like to discuss the ways that new techniques are being used in the field of conservation biology to address issues related to the conservation and management of both native plant communities and individual species. The difference between the use of molecular methods for

Supplying Plants for Revegetation: A Buyer's Expectations

Author: Roger Lord

PP: 143

Revegetation or the use of indigenous local provenance plants for rehabilitation or restoration of plant communities is the accepted practice in Melbourne Water Waterways and Drainage Group and is used as part of waterway management. Revegetation programs within Melbourne Water are included in:
  • The Stream Frontage Management Program which is an incentive scheme to encourage rural land owners to fence and revegetate waterway reserves in their property;
  • Revegetation associated with capital works, e.g. waterway stabilisation using rock;
  • Drainage Schemes which are funded by developers of subdivisions and provide a means of ‘greening’ a new development along installed drainage infrastructure, ie. open drains and modified watercourses;
  • Significant sites which involve community/"friends" groups.

Revegetation demands a plant supplier who has a degree of knowledge in botany, ecology, and genetics and has a willingness to incorporate these disciplines into horticulture.

Main Expectations. The main

Operating an Indigenous Plant Nursery: My Experience in the Field

Author: Graeme L. Stockton

PP: 145

INTRODUCTION

Indigenous plant nurseries are a relatively new concept in the horticultural industry. In Victoria most have developed within the last 15 years. These nurseries are essentially based on ecology rather than horticulture, therefore, the way they operate is vastly different and sometimes contradictory to conventional nurseries.

Some Observations of the Effect of Smoke on the Germination of South-Eastern Australian Native Species

Author: Greg Bain, David Lockwood

PP: 146

INTRODUCTION

An initial "screening" program was initiated in 1995 by the Melbourne Indigenous Seedbank (MIS) to investigate the effect of smoke on selected Victorian plant species. These traditionally difficult-to-germinate species were selected because they belonged to the families discussed by Dixon et al. (1995) as being responsive to smoke treatment in Western Australia. The seed of species that were selected for testing came from the seed storage facilities of the MIS or from donations of seed from the community. Species not acquired from storage or donation will be collected and tested through 1996–97 to complete the "screening" process. Additional information in relation to the effect of plant-derived smoke upon germination has come from "smoking sessions" facilitated by Greening Australia Victoria, which have enabled nursury growers to smoke treat seed from selected species and then propagate these under conventional nursery conditions.

Monitoring Variation in the Propagation Environment

Author: Ken James

PP: 149

INTRODUCTION

Environments in greenhouses never stay constant, varying between day and night, and often having different zones within a greenhouse to such a degree that the microenvironment of propagating trays and pots may not stay within acceptable limits. Greenhouse environments and designs are detailed in texts such as Garzoli (1988) but little information is available on microclimate changes within a greenhouse. Five greenhouses at Burnley were monitored over several weeks using electronic data recording equipment and infrared thermal imaging techniques. Spatial and temporal variation of temperatures were monitored in the microenvironment of the greenhouse and the microenviromnent of the propagating pots.

Significant variation of temperatures occurred in a glasshouse heated with an overhead radiant gas heater located along the gable ridge. A gas burner produced hot gases which passed along the length of the tube causing it to heat up and radiate heat to the plants below. The

Design and Construction of a Controlled Environment for Propagation of Ornamental Plants

Author: Clive Larkman

PP: 150

DESIGN CONSTRAINTS

We were using in-bed electrical cables which were proving inefficient and expensive to run. Determined to reduce the heating costs by at least 40% for our 60 m2 of heated propagation beds which were costing us approximately $800 per winter month to run, the first decision was which irrigation system to use? Fog, mist, or high pressure mist? The second was to determine which method of heating and therefore what fuel type to use. We were working with an existing tall tunnel, 18.5 m × 6.2 m × 3.4 m (l×w×h) which was used to house stock plants.

Managing the Environment for the Production of Quality Plugs

Author: Russell Slobodluk

PP: 153

The essence of plug production is in the ability to control the environment. For plug production to be cost effective maximum outputs must be achieved for each square metre of available greenhouse space. The provision of optimal conditions must be the aim throughout the production process, which can take between 3 and 12 weeks depending upon species grown.

Seed Storage. The process begins by using the highest quality seed which has been stored in a dry conditioned atmosphere between 12 to 15C and 35% to 40% RH. Seed will tolerate fluctuations in temperature, but viability and vigour are greatly reduced with fluctuations in RH, particularly if levels increase.

Sowing. Sowing is done mechanically on either drum or needle seeders depending upon the shape of the seed. Accuracy is the key, not speed, so the control of dust, wind, temperature and light in the sowing area is important. Seeders must always be kept clean and well maintained.

Germination. The highest percent germination

Horticultural Research at the Royal Botanic Gardens

Author: Rob Cross

PP: 154

INTRODUCTION

The Royal Botanic Gardens Melbourne has recently established a formal horticultural research program. The main areas of research are Phytophthora, prospecting Proteaceae for the horticultural industry, and the photoautotrophic micropropagation of Banksia for the horticultural industry and Caladenia for conservation.

Micropropagation of Evolvulus pilosus

Author: T. Yamamoto, T. Kiyohara, N. Ikeda, K. Toki

PP: 155

INTRODUCTION

In Japan Evolvulus pilosus Nutt. ‘Blue Daze’ also known as "American Blue" has been popular as a potted ornamental for several years. Although the plant is easily propagated by softwood cuttings, micropropagation is expected to be the better technique for obtaining a large number of the elite clones of this plant. This paper describes the regeneration of the plant through organogenesis using three types of explants; nodal segments, shoot internodes, and leaf cuttings.

Propagation of Michelia and Manglietia

Author: Don Teese

PP: 156

SEED

Plants produce clusters of seed pods varying from a few to 20 ormore capsules, each containing one or two seeds. Hard black seeds are surrounded by flesh varying in colour from orange to pink or red. Pick the capsules when they first begin to split or show colour when exposed by cutting. Split open fully to remove seed from capsules, squash the flesh or remove from around the seed. Some growers recommend washing the oil from the seed with detergent in case this inhibits germination. The only species for which we find this may be necessary is Michelia champaca, which has been difficult to germinate. Most varieties germinate easily if the seed is fresh. The seed should not be allowed to dry out as viability drops markedly. Under Australian conditions the seed can either be sown inside or outdoors. Inside provides greater environmental control and may be necessary for colder regions. No pregermination treatments are required. Netting may be necessary to prevent losses to birds.

Propagation Techniques for a New Flower Bulb Crop (Lachenalia)

Author: Josephine G. Niederwieser

PP: 158

A NEW CROP

Lachenalia is a bulbous genus endemic to the south western Cape in South Africa (SA) and belongs to the Liliaceae family. The genus comprises approximately 110 species and a number of these are grown commercially on a small scale, e.g. L. aloides. ARC-Roodeplaat developed, through breeding and selection, a number of cultivars which are currently being test marketed in Europe as both garden and potted bulbs.

Sturt Peas: Propagation and Breeding Strategies for Different Markets

Author: Greg Kirby

PP: 56

INTRODUCTION

Sustained commercial production of Sturt's desert peas (Swainsona formosa) has not been successful, despite many attempts in several parts of the world, see Williams and Taji (1991) for some of the history. Barth (1990) summarised a study of cultivation and production requirements and a survey of three potential markets: cut flowers, cut runners, and pot plants. She emphasised the need for a breeding programme to produce cultivars suitable for each market. The great variability observed between plants grown from seed collected from natural populations showed that there was an opportunity for breeding Sturt peas in Australia for the different markets, particularly pot plants and cut flowers.

The Flinders University breeding programme began with a germplasm survey of plants grown in pots and a garden from seed collected from natural populations in Western Australia and South Australia. Plants with characteristics deemed most appropriate for each of the markets were

Reflections on the History of Irish Gardening: Thelma Swash Memorial Lecture1

Author: Donal Synnott

PP: 163

In 1995, was the bicentenary of the founding of the National Botanic Gardens, Glasnevin, which gave many of us at the Gardens the excuse to reflect upon the history of Irish horticulture and on Glasnevin's place in that history.

History is sometimes seen as the story of influences from abroad and this approach can certainly be applied to the history of gardening in Ireland. The Romans, as far as we know, didn't get to Ireland, or if they did they just came over for occasional forays, so we wouldn't expect any Roman influences in early Ireland. The first wave of invaders of which we have any record is that of the Vikings and, from archaeological investigations, we know that gardening was not high on their agenda although fruit was gathered wild from the surrounding countryside.

A monastic tradition has existed in Ireland since early Christian times and continued after the Norman invasion. There is evidence that the Normans were responsible for introducing a large number of garden

The Right Rootstock for a Good Graft Stick

Author: Tom Wood

PP: 167

INTRODUCTION

Propagation by grafting is expensive in terms of resources and labour input and is justified only because of the potential for enhanced returns for the finished, often highly desirable, plant. Failure of grafts can therefore be very costly and must be avoided.

Use of the correct understock is fundamental to success but there is such a confusing range of terminology applied to planting stock that while propagators know the size and type of stock required, they cannot be certain of asking for it correctly, let alone receiving it. There is, therefore, a need for a simplified and generally accepted specification for stocks and planting material. The aim of this short paper is to address some of the misunderstandings current within the trade and to propose the adoption of specifications and definitions already used in forestry.

Liner Production Management and Ergonomics

Author: Pat Fitzgerald

PP: 169

INTRODUCTION

Fitzgerald Nurseries is a new nursery business, specialising in the production of liners and plug-rooted cuttings. It was found that attention had to be given to planning the short-term and long-term objectives of the business simultaneously. Without proper care and planning these two objectives may be self-conflicting, for example, the provision of proper facilities maybe at the cost of production materials. It therefore became necessary to put resources into producing our crops at a profit and to a high standard to generate a cash flow. Many liner nurseries must take such broad factors into account as the develop, expand, and become more efficient.

The management of limited resources in such a situation is of paramount importance. The use of these resources has to be optimised and each mistake made must be a resource in itself. If a mistake is not too major the business will continue provided the error is corrected and the procedure documented for all staff

Pest Control and Production Systems for Liner Production

Author: Kleran Dunne

PP: 173

VINE WEEVIL CONTROL

Since withdrawal of approval for the pesticide Aldrin, 10 years ago, life has been difficult and expensive. It is not acceptable to supply vine-weevil-infested liners, so on this nursery controlling vine weevil takes top priority, with a strict hygiene programme on the nursery combined with the latest chemical controls. In the view of this author, pesticides as toxic as Aldrin are inappropriate for liner production in any case, because of the dangers associated with application of such chemicals, handling plants afterwards, and the safety of workers and customers.

The nursery has also experienced problems with pesticides introduced as Aldrin replacements, for example, poor control (promises of a miracle product which isn't always the case), damage to crops, and high purchase cost.

In the last 2 years, the most promising development in vine weevil control has been the introduction of nematodes. All liners on this nursery will be treated with nematodes in

Experiences with Carbon Dioxide Enrichment for Production of Rooted Cuttings

Author: Willem Sanders

PP: 175

INTRODUCTION

Trials at the Research Station for Nursery Stock at Boskoop have already shown that carbon dioxide (CO2) enrichment has a positive effect on rooting and growth of cuttings, particularly rooting percentage and fresh and dry weight (Table 1). In 1992 these positive results from the Research Station encouraged Sanders Nurseries to invest in CO2 enrichment equipment and to use it in all propagation. The technique has proved to be very beneficial for this nursery and has never given negative results, though sometimes there has been no difference between use and non-use of CO2 enrichment.

When producing cuttings under low polythene covers, if there is no CO2 enrichment, carbon dioxide levels under the polythene may drop below the threshold for plant growth. For example, measurements at Willem Sanders Nurseries on 1 day in March showed 3000 ppm C02 under the polythene produced by plant respiration during the night. The day started with fog but the sun broke through

The Effect of Type and Rate of Controlled-Release Fertiliser on the Performance of Hardy Nursery Stock in Containers

Author: Michael J. Maher

PP: 178

Four controlled-release fertilisers (CRFs): Ficote 140 (14N-3.5P2O5-6.5K2O), Multicote 8 (18N-2.6P2O5-9.8K2O), Osmocote 12-14 month (15: 4: 9), and Planta cote 12M (15N-4.3P2O5-12.5K2O) were compared for the production of hardy nursery stock. These fertilisers were incorporated into a peat compost at three rates to provide 450, 750, and 1050 g N m-3. Five plant subjects were studied: ×Cupressocyparis leylandii ‘Castlewellan Gold’, Choisya ternata, Ligustrum ovalifolium, Ulex europaeus ‘Strictus’, and Ozothamnus ledifolius. The four fertilisers and three rates were applied in a factorial design for each subject. Rooted cuttings were potted up into 2-litre pots in May and placed in a bed with overhead irrigation. The plants were evaluated in December and May for vigour, colour, height, fresh weight, and marketability. Higher rates of CRF resulted in increased fresh weight and other characters evaluated for most of the plant subjects and fertilisers tested. Plants were more responsive in terms of vigour and marketability than in colour and height. Ficote and Osmocote were the most consistently successful of the fertilizers. Multicote gave poor results with Ligustrum but was satisfactory with the other subjects. Ulex performed poorly with Plantacote. These results may be related to trace element nutrition.
Nutrient Survey of Nursery Stock in Ireland and U.K. Including Nutrient Reserve Analysis in Controlled-Release Fertiliser and Leaf Analysis

Author: M. Prasad

PP: 183

Bord na Móna Horticultural Division is providing technical support to growers in Great Britain and Ireland, involving measurement of available nutrient, nutrient reserve in controlled-release fertiliser(CRF) and analysis of foliage. There was a significant inverse relationship between the nutrient reserve in CRF and time of potting. This relationship is not linear and there are strong indications that for the 12 to 14 month formulations of CRF, most of the nitrogen has been released, by 8 to 10 months. From the data obtained in 1993/ 95 we have compiled "normal" levels of major nutrients of over 50 species. In addition the frequency distribution of micronutrients from over 100 samples has been compiled. This type of information will be invaluable for diagnostic purposes and to make an informed decision whether to top-dress in spring.
Propagation of Rhododendrons at Millais Nurseries

Author: David Millais

PP: 190

INTRODUCTION

Millais Nurseries is a specialist rhododendron and azalea nursery producing around 650 different varieties ranging from tiny dwarfs to large forest trees. It was started as a retail nursery in 1970 by Ted Millais, the author's father. Current production is approximately 40,000 plants per year. The market ranges from retail customers wanting one or two rare plants for their collection either from our plant centre or by mail order throughout the world, to large garden centres. The nursery also undertakes contract growing for the wholesale market.

Rhododendrons are not the easiest plants to propagate, but Millais Nurseries offers such a wide range that most have to be propagated in-house. In order to improve efficiency and output, a new propagation house was installed in 1993 with 70m2 of roller benching, thermabed hot-water heating, and mist and wean facilities. The house contains five beds and each is individually controlled by electronic thermostat and electric leaf

Eucalyptus as a Cut Foliage Crop

Author: Mary C. Forrest

PP: 194

Single stem, 1-year-old specimens of Eucalyptus gunnii were planted in four treatments of single, double, triple, and quadruple rows at a spacing of 1.75 m between plants, both between and within rows (densities of 1937, 2431, 2657, and 2787 plants ha-1). In each year of the experiment foliage was harvested from autumn until early spring. Length, weight, and form of foliage, whether juvenile, adult or discard, was noted. The plants were then coppiced. The cumulative weight per treatment was measured. There was no significant difference between treatments or in the treatment/year interaction. The mean weight of material harvested per plant planted in consecutive years was 0.58, 1.92, 1.07, 1.02, 1.07, and 1.43 kg and is within the range reported from England and Germany (0.5 kg to 3.0 kg per plant). The percentage of juvenile foliage harvested in each consecutive year was 19.9%,28%,68.6%,76.6%,73.6%, and 66.8% and this indicates the effect of severe pruning on the production such foliage.
Recent Research on Propagation at the Research Station for Nursery Stock, Boskoop

Author: Bernard P.A.M. Kunneman

PP: 197

INTRODUCTION

This paper gives an overview of some of the propagation research projects of the Research Station for Nursery Stock at Boskoop. There are several current research projects, this paper concentrates on the following subjects:

  • Improvement of seed germination
  • Propagation of Acer platanoides
  • Propagation of nematode free perennials
  • Conditions during rooting
  • Rooting leafless hardwood cuttings

With cuttings, research was undertaken on CO2 enrichment; stock plant treatments; rooting conditions of cuttings; reduction of flowering during rooting of Pieris; development of systems for rooting of leafless hardwood cuttings and improvement of the quality of cuttings. Use of cuttings for nematode-free production of perennials was also trialled. Tissue culture techniques were developed to propagate rootstocks for fruit trees (Malus, Pyrus, and Cydonia) and for propagation of Acer and Paeonia. The research on seeds concentrated on the effect of pretreatment conditions on

Breeding New Leptospermum Cultivars

Author: Peter Ollerenshaw

PP: 59

INTRODUCTION

Leptospermum, commonly called tea tree in Australia, belongs to the family Myrtaceae. There are currently 85 recognised species, three of which occur only in South East Asia. One species occurs in both South East Asia and Australia. Another species occurs in southern Australia and over most of New Zealand. The remaining 80 species are endemic to Australia. They are often found on the edges of swamps or rivers, but may also be seen on rocky ridges or sandy sites. Leptospermum species are commonly shrubs 2 to 4 rn high, however they can also occur as prostrate groundcovers or trees to 18 m high. Most species have ornamental merit and are easily propagated from seeds or cuttings.

Flower colour is generally white, although there are pink forms and a few species that are red or mauve. In our locality flowering begins in Sept. and you can have a continuous succession of species flowering for 5 to 6 months. Leaf shape and colour is quite varied and some species have strongly

Propagation of Perennials at Schram's Nurseries

Author: Flip Schram

PP: 201

INTRODUCTION

The nursery was established in February 1981 to supply perennials for the author's landscaping business. At the time, perennials were not grown in Ireland on any commercial scale and the nursery soon started to supply perennials to the trade. In 1987 it replaced the landscape business as the author's sole occupation.

At present 88% of plants produced are sold to garden centres, 4% to the wholesale trade, 4% to export, mainly Northern Ireland, and 4% to the landscape trade.

Because of Ireland's location in the EU and because it is an island with a small population, it is important to offer a diverse range of plants and a good service. Therefore, approximately 1500 different taxa of perennials are grown, from propagation stage to final product. Marketing, promoting, and delivery are all undertaken in house. Recently, several new perennial nurseries have been established in Ireland and it is now not so important to carry such a wide range. Instead, it is important to

The Effect of Irrigation Systems and Peat Grade on the Production of Hebe‘Mrs. Winder’

Author: C. Kirkland, A. Hunter, M. Maher, M. Prasad

PP: 203

The performance of ebb and flood, capillary, and overhead irrigation systems was compared using rooted plants of Hebe>‘Mrs. Winder’in 2-litre containers, with peat-based growing media having air filled porosity (AFP) values ranging from 5% to 25% and containing standard recommended doses of controlled-release fertiliser. The plants attaining the greatest height were produced on the ebb and flood beds. Plants on the capillary beds were smaller and attained the lowest root index. Plants on the overhead-spray beds were like those of the capillary beds but scored more highly for marketability. Even with Mypex sheeting, rooting-through occurred on the ebb and flood beds but not on the capillary beds. The most water efficient irrigation system was ebb and flood. Overhead was the poorest.
The Nursery Stock Industry In Northern Ireland

Author: David Kerr

PP: 208

INTRODUCTION

The nursery stock industry in Northern Ireland is relatively small and diverse, when compared to that in Great Britain, with growers often also involved in retailing and landscaping. The domestic market is characterised by limited opportunities, given that Northern Ireland is a small region with a total population of 1.5 million. Growers tend to grow what they know they can sell and expansion of the industry is dependant on exports.

At present the level of exports is low, being estimated at approximately £500,000 per annum, mainly going to Great Britain.

Clonal Evaluation of Escallonia and Cytisus

Author: Cathal G. Ellis

PP: 212

INTRODUCTION

The rapid increase in the production of container-grown hardy ornamental nursery stock in recent years has underlined the need for quality and uniformity in stock plants. As production increases, so too does the diversity of available species and their associated cultivars, leading to some taxa being misnamed in the process. This leads to confusion within the industry. For example, of eight accessions of Escallonia ‘Peach Blossom’, received by the Research Station at Loughgall, only one conformed with the true varietal description. Similarly, 50% of the accessions of E. ‘Donard Star’ were wrongly named, being in fact E. ‘Donard Radiance’. In the remaining cultivars between 15% and 40% of the stock was incorrectly named. In the early stages of the evaluation of Cytisus it was discovered that all seven accessions of Cytisus ×praecox ‘Albus’ were wrongly named and did not match the general varietal description. Most variability recorded to date was a result of incorrect naming of

The Production of Clean Plants in the Laboratory

Author: Alan C. Cassells

PP: 216

INTRODUCTION

Tissue-culture techniques complement conventional methods for the production, storage and propagation of disease-free plants. In the propagation of pathogen-free and contaminant-free plants, there are four important elements:

  • The problem of detecting microorganisms in the stock plants.
  • The requirement to develop an appropriate protocol to eliminate potentially harmful microorganisms.
  • The problem of confirming the elimination of microorganisms.
  • The requirement to maintain a good health status during multiplication and storage of the clean or elite stock.

It is increasingly the situation that elements of both the in vivo and in vitro approaches are combined in modem practice. The risks in both in vitro and in vivo techniques for the production of clean planting material will be considered here in the context of good working practice.

A Tube Method for Grafting Small Diameter Scions of the Hardwoods Quercus, Fraxinus, Betula, and Sorbus in Summer

Author: G.C. Douglas, J. Mc Namara, D. Thompson

PP: 221

In conventional grafting of oak and ash in February, the graft viability over 3 years was 15% and 97%, respectively, with 64% of oak clones responding and 100% of ash, using scions from mature trees. Using single node scions from these grafted plants, epicormic shoots, crown shoots, and a silicone tube to hold graft unions we recorded improved rates of graft viability by summer grafting. All oak and ash clones made viable grafts with efficiencies of 18% to 100%. Summer grafting of hardwoods allows several serial grafts per year and potential to rejuvenate tissues.
Use of In Vitro Plants in the Irish Hardy Nursery Stock Industry

Author: A.J. Sayegh, Fintan P. Moran

PP: 227

Micropropagation has become an integral part of the horticultural industry. A survey was conducted to enquire into the usage of in vitro plants by Irish nurseries. The amount of tissue culture material used does not exceed 5%. The small size of the Irish industry means that the Irish market for tissue culture material is very small. The vast majority of users of tissue culture material recognised its great advantages but found suppliers unreliable in terms of delivery date and quantity but not quality. The unreliability was explained by the peaks inherent in hardy nursery stock production.
Nursery Stock in Finland

Author: Christiane Kummer

PP: 231

INTRODUCTION

Finland is on the east of northern Europe, in Scandinavia, between the 60th and 70th degree of latitude and so is as far north as Sweden, Norway, Greenland, and Alaska.

About 75% of Finland's area of 337,000 km2 is forest and woodland, and 10% is covered by lakes. Half of the 5 million Finns live in the very south of the country.

The climate is cold temperate, potentially subarctic but comparatively mild because of the moderating influence of water (Baltic Sea, North Atlantic Current, 60,000 lakes).

Hardy Woody Plant Propagation at the Royal Botanic Gardens, Kew

Author: Annette Wickham

PP: 234

INTRODUCTION

Hardy woody plants are propagated at the Royal Botanic Gardens, Kew, in the Temperate and Arboretum Nursery. In total there are four nurseries on the site at Kew, and a further nursery at Kew's satellite garden at Wakehurst Place, Sussex. Each nursery specialises in a particular range of plants:

  • Alpine and herbaceous.
  • Tropical nonwoody.
  • Micropropagation (concentrating mainly on endangered plant species including orchids.
  • Temperate and arboretum (a merging of two nurseries in effect on one site, where mainly woody plants from sub-alpine to tropical rainforest habitats are propagated and grown).

This paper will concentrate only on the Arboretum Nursery and the propagation and cultivation of hardy woody plant species.

The nursery covers an area of 6078 m2 of which 889 m2 is glass, 2975 m2 open ground area, 175 m2 polytunnels, and 198 m2 sandbeds.

There are three full-time members of staff: a nursery manager, responsible for the general overall running of

Propagation and Plant Production in Taiwan

Author: Donnchadh Mac Cárthaigh

PP: 240

INTRODUCTION

The development of Taiwan in the past 30 years has been remarkable. It has changed from an agrarian to a highly sophisticated industrial society which now has probably the highest foreign reserves of any country in the world. It is slowly adjusting to the new GATT conditions which will mean less protection for agricultural and horticultural producers.

The horticultural industry has been very strongly promoted by the Taiwanese Council of Agriculture. They have sent many people to the U.S.A. and Europe to improve their expertise so that the expansion of horticultural production has been nothing short of phenomenal. This is reflected in the figures given in Table 1.

Development of New Ornamental Plants in Australia

Author: Angus Stewart

PP: 61

As a fresh-faced young graduate some 15 years ago I was drawn towards the area of genetic improvement of Australian plants. This paper presents some observations and reflections on the present and future of ornamental plant cultivar development with Australian species.
Propagation and Culture of Hebes at Lowaters Nursery

Author: Ian Ashton

PP: 243

INTRODUCTION

Lowaters Nursery is a wholesale nursery business located near Southampton on the south coast of England. It has approximately 2.3 ha of production space, 80% of this is modern heated glasshouse and nearly all production space has capillary beds.

More than 1 million cuttings are struck each year, of these 800,000 are used after grading. Half of this production is sold in rooted-cutting or 9-cm liner form with the remainder going through various stages to be sold as garden centre quality plants.

Since hebes make up more than 50% of annual sales, Lowaters is one of the largest hebe producers in the U.K. Our position requires us to have production methods designed to overcome the reputation of hebes for being difficult to grow, largely because of the susceptibility of some species and cultivars to downy mildew.

The production methods used by Lowaters Nursery described in this paper are by no means the only way of growing hebes, but they are the ones that work for this particular nursery.

Extending the Range of Plants for the Nursery Stock Industry

Author: R.F. Murphy

PP: 246

The main objective of this project is to ensure that rare plants, or those of outstanding garden worthiness, are not lost. These plants will eventually be introduced into the trade thus expanding the nursery plant range.

Since it started in 1995 the project has successfully collected and propagated many woody, herbaceous, and alpine cultivars. The majority of these plants are very scarce and several have arisen as sports or by selections from existing plants. Several good garden plants are still scarce because of problems in propagation.

The first stage is location of the plants and, to this end, the project has targeted the most important gardens in Ireland. Assessment and selection of the plants then begins. Special attention is paid to disease resistance as well as any particular characteristics for which the plant is selected. Samples are then collected for propagation. Cuttings under mist is the main propagation method but grafting and micropropagation is also carried out

New Methods For Germinating Orchid Seeds

Author: Hanne N. Rasmussen

PP: 251

BIOLOGY OF THE ORCHID SEEDLING

Plant seedlings in their first stages are heterotrophic and depend entirely on nutrient reserves deposited during the maturation of the seed. The mother plant thus provides support until the seedling has developed a photosynthetic apparatus.

Orchid seeds are very small ("dust seeds"), being less than 1 mm long including the testa. A concentrated reserve of protein and lipids is stored in the embryo but is necessarily small. The embryo is a poorly differentiated body of at most 200 or 300 cells. During germination the reserves are mobilized but because the heterotrophic phase is extremely long and the seed reserves so limited, no orchid seedling develops far without external nutrient supplies. The seedling relies on an alternative source of nutrition, i.e. the breakdown of fungal hyphae on which the plant parasitizes. The radicle is completely specialized into a mycotrophic organ; until the seedling produces adventitious roots and leaves it cannot

Application of Antagonistic Microorganisms to Seeds to Control Fungal Plant Pathogens

Author: Birgit Jensen, Inge M.B. Knudsen, Dan Funck Jensen, John Hockenh

PP: 256

INTRODUCTION

During the next decade biological control may become an important component of plant disease management practices. The demand for alternatives to chemical control of plant pathogens has become stronger owing to concerns about the safety and environmental impacts of chemicals. Development of fungicide resistance, lack of effective chemical solutions for specific pathogens, and the fact that pesticides are not allowed in organic farming systems has increased the need for development of biological control agents (BCAs). Biological control can be practiced in three ways:

  1. By deliberate application of beneficial microorganisms which suppress plant pathogens,
  2. By deliberate application of organisms which induce resistance in the host plant;
  3. By cultivation practices which enhance natural disease suppression (suppressive soils).

This paper deals with the first category and focuses primarily on biocontrol obtained by application of fungal antagonists to seeds.

Production and Storage of Perennial Seed

Author: Klaus R. Jelitto

PP: 263

The great majority of perennial seed are specially raised for our company in regions that are particularly well suited for that particular species. Thus, we control and inspect a cultivation network that stretches from north of the arctic circle through the whole of Europe to northern Italy and the northern part of the U.S.A. as well as Chile. Altogether, we have people producing seed for us in 23 different countries. We have no production in tropical or subtropical regions, since we specialize in hardy perennials. With these plants the source (origin) of the seed plays a major role in determining the "hardiness" of the plants.

Sometimes, however, we really do have to seek and find particular seeds. This can be very difficult and may take years—particularly when we need original material from the natural location. Just one example: For many years there was a certain Campanula raineri on the market, which actually was not C. raineri, but C. carpatica var. turbinata. A botanist

Seed Production in Horticulture

Author: Palle Sørensen

PP: 265

THE DEVELOPMENT OF DANISH HORTICULTURAL SEED PRODUCTION

Danish seed production has existed for several hundred years. At first all growers supplied their own or were at least partly self-sufficient, then in the later part of the last century it changed. Commercial production started.

Market gardeners were the first to turn to commercial seed production, but production moved to agriculture at the start of this century. This occurred mainly because of growing competition.

Around Wold War I cabbage seed production was substantial. In 1919 the total seed production area was 2873 ha of this 1738 ha was used for cabbage seed. Most seed was exported to the U.S.A. and Germany. This seed production continued until the 1960s with shifts in the species produced. Some species were grown because they were traditionally grown rather than because of the favourable growing conditions. As vegetable production became more specialized the demand rose for more efficient seed production in the

Handling of Recalcitrant Tropical Tree Seeds

Author: Kirsten Arnfred Thomsen

PP: 267

INTRODUCTION

A large number of tropical tree species have recalcitrant or intermediate seeds, i.e., seeds that are intrinsically short-lived, as they do not tolerate drying to the same extent as orthodox seeds and cannot be stored at low temperatures. For most species the optimal conditions during seed handling and storage have not yet been established. This presents serious problems with regard to the short-term utilization of the species and the long-term conservation of the genetic material.

This is the background for a recently started project, funded by Danida, with the objective of determining desiccation tolerance and storage conditions for 20 to 25 important tropical tree seed species. The project is coordinated by IPGRI (International Plant Genetic Resources Institute). DFSC (Danida Forest Seed Centre) provides technical backstopping and a large number of seed centres and research institutes in Africa, Asia, Central, South, and North America, as well as Europe,

Precision Drills and Vacuum Seeders for Vegetable Seeding

Author: Haarby Forge, Art Smith

PP: 270

Haarby forge at Southwest Fyn has been in existence for 30 years and has, among other things, specialized in machinery for vegetable production. They manufacture the Stanhay sowing equipment — the most widely used type in Denmark. In vegetable seed sowing two techniques are mainly used — precision drills and vacuum seeding. Stanhay manufactures both types which are built on a parallel chassis that rides on two pressure rollers. In this way even sowing depths are maintained.

When using the Stanbay 870 or 985 precision drill you have a reliable machine for sowing a range of vegetable seeds both natural (no coatings) or pelleted. You can maximise the profitability of your seed-produced crops by selecting the proper choke, base, and seed belt (ribbed, plain, or plastic) for the metering unit; getting the right hole seize; and deciding whether to use single, double, or triple rows.

The seed hopper contains a choke which regulates the amount of seeds in the chamber; the seed belt then

From Seed Technology to Seed Products

Author: Peter Van Der Toorn

PP: 271

Research developments over the past 20 years in the areas of precision sowing, crop protection, and germination performance as they relate to the vegetable and flower seed industry are discussed. It will be shown that technology oriented research in these fields has led to innovative, value-added seed products. The marketing of these seed products is targeted at the needs of growers. Products that are discussed include "100% usable plant seed" based on pregermination technology, "high vigor seed" based on priming technology, and "seed plus shield" based on coating technology.
Vigour Test In Oil Seed Rape And Peas

Author: Søren Ugilt Larsen

PP: 284

INTRODUCTION

A vigour testing experiment with spring oil seed rape (Brassica napus) and pea (Pisum sativum) was performed. The aim ofthe study was to subject seeds of the two species to "controlled deterioration" and then compare the results of a vigour test with field observations.

There is interest in examining if there is a correlation between the results of a vigour test and the field performance of the seeds to better predict seed quality. In order to test this, a vigour test was applied to a number of seed lots, and the test results were compared to results of field trials, i.e. trials where the development of plants of the different seed lots was followed during the growing season.

If the vigour test is to be considered as applicable there must be a close correlation between its results and results of the field trial, i.e. seed lots with the best test results should have the best field performance. Thus, on the basis ofthe vigour test it should

Propagation of Cape Proteaceae, Ericaceae, and Restionaceae from Seed

Author: N.A.C. Brown, J. Van Staden, G. Brits

PP: 63

The Cape Floral Region possesses the richest temperate flora in the world. The dominant vegetation of the Cape Floral Region is the fynbos which is typified by the presence of members of the Restionaceae (Cape reeds and grasses), the Proteaceae (sugarbushes, pincushions, and conebushes), Ericaceae (Cape heaths), and a number of endemic families. Many of the fynbos species are of outstanding horticultural potential. Seeds of most species are dormant and research has shown that very specific environmental cues are required for germination. It has also been shown that fire, a natural feature of the fynbos environment, provides the major cues for seed germination in the wild. During the last five years, considerable progress has been achieved in understanding seed dormancy mechanisms in the Proteaceae, Ericaceae, and Restionaceae.
Germination and Priming

Author: Henry Damm Hansen

PP: 289

The following paper will present some of the basic physiological mechanisms underlying the germination of orthodox seeds. The same mechanisms will be invoked in an attempt to explain "seed priming".

The most important physical/chemical factors influencing the germination process are the availability of water and oxygen and the influence of temperature. The following discussion will make reference to Fig. 1.

When dry seeds come in contact with a sufficiently humid substrate the seed will imbibe water very quickly if the seed coat permits it — this is called Phase 1. Phase 1 is a passive process and will happen also in dead seeds. The seed swells and the water content will level at a plateau. During the next phase, Phase 2 or lag period, the water content will only increase marginally. The duration of Phase 2 varies widely and is dependent on plant species. To a lesser degree it varies by seed lot within a species, however, it is differences in the length of this period between

Storage of Orthodox Seeds

Author: E. Nymann Eriksen

PP: 292

Seeds have an unique position in the world of plant propagation because they can be dried down and stored for long periods of time. This makes seeds ideally suitable for long-term storage (gene bank preservation) and the shipping of plant materials. The oldest recorded living seed is about 240 years old. This seed is from the species Nelumbo nucifera, however, there is doubt about the dating of this seed. In addition, we have other reports of germinable seeds about 100 to 150 years old. For tree seeds, companies are not interested in storing for more 10 to 20 years.

Seeds suitable for storage can be divided into two groups. One group, orthodox seeds, is desiccation tolerant and suitable for storage. The second group is desiccation sensitive and therefore very difficult or impossible to store. The desiccation sensitive seeds are called recalcitrant seeds. The largest group is the orthodox seeds and the following paper will only address these kinds of seeds.

Many different conditions

Breaking of Tree Seed Dormancy at Controlled Moisture Content

Author: Martin Jensen

PP: 296

INTRODUCTION

In nature it is very common for seeds to have mechanisms that delay germination for shorter or longer periods. This delay or temporary inhibition of germination is often termed seed dormancy, and covers a range of different physical, chemical, and biological conditions in the seeds. More than 60% of Danish tree and shrub seeds have some kind of dormancy. In commercial production seed dormancy constitutes a major problem, causing losses of viable seed resources and reducing possibilities for optimizing the size of the production to the demand of the market.

In breaking physiological dormancy by a prechilling or cold stratification treatment, the seed has traditionally been fully hydrated and kept at a near maximum moisture content (MC), sometimes mixed with peat moss or sand, and prechilled at 2 to 5C for a time period required for the seed to initiate germination at the storage temperature. The duration of the prechilling treatment depends on the species and the

Controlled Moisture Content During Release of Dormancy in Tree Seeds — Large Scale Handling

Author: Henrik G. Knudsen

PP: 305

The Tree Improvement Station (TIS) is part of the National Forest and Nature Agency under the Ministry of Environment and Energy. TIS has three main objects:
  • Seed supply to the Danish forestry, both state and private nurseries and forest districts;
  • Nursery production of plants to the Danish state forest districts;
  • Tree improvement in order to secure seed supply of the best genetic material in the future by establishing seed orchards and seed stands in a great variety of forest tree species. Furthermore TIS has a close cooperation with Danida Forest Seed Centre in seed testing of tropical tree species and in projects in developing countries.

The release of dormancy is in many tree species necessary in order to achieve germination. In nature this is taking place during the winter under the cold and humid conditions on the forest floor. This has been copied and improved by nurserymen over the years. Seeds have been collected and placed in cold storage where dormancy is released

Machine Grafting of Grapevines using the Spinks Grafting Machine

Author: Gerardo G. Villanueva, Steve Maniaci

PP: 309

INTRODUCTION

Sunridge Nurseries, Inc. is a wholesale grower of grapevines for the fresh market and primarily for wine grape production. Our production includes:

  • Bench-grafted vines grown in the nursery in 2 in. × 2 in. × 10 in. deep tubes and sold as green plants for transplanting in spring and summer.
  • Bench-grafted vines grown in the nursery, transplanted into an outdoor field nursery row, and dug in winter for sales as dormant vines for early spring transplanting.
  • Rootstock rootings that are stuck directly into outdoor field nursery rows in late winter, grown for one season, and dug in winter for sales as dormant vines for early spring transplanting. These vines are field grafted 1 year after transplanting into the vineyard.
  • Softwood mist-propagated varietals and rootstocks grown in 4-in. pots or 2 in. × 2 in. × 10 in. deep tubes for sales as green plants for transplanting in spring and summer.
  • Hardwood propagated varietals and rootstocks grown in 4-in. pots or 2 in. × 2 in. × 10 in.
Rose Budding with T-Bud Technique

Author: Bruce Frost

PP: 311

PRE-BUDDING CARE

A pre-plant fertilizer (8–8–8 at 30 gal per acre) is shanked (drilled) in on both sides of where the hardwood cuttings are planted in November. The cuttings are kept watered on a weekly basis until budding time in early April. By then we have 12 in. or more shoot growth and good root development.

Giant Sequoia in the Sierra Nevada

Author: Jim Sellers

PP: 312

The ecology of giant sequoias has been a subject of intense interest for the last three decades. Fire, mycorrhizal fungi, squirrels, and insects have essential roles in the survival of the sequoia forest. Managers must implement strategies to create natural conditions in areas overprotected from naturally occurring processes. Pre-Euroamerican forest species and natural processes are the management goals of restoration.
"The San Joaquin Valley" Question-Answer Period

Author:

PP: 316

Jim Booman: I have a question about the redwoods (Sequoiadendron giganteum). I was up in the groves yesterday and every three seconds there was a cone falling, ricocheting off the branches, and coming quite close. Was that the squirrel? Secondly, unlike the coastal redwoods (Sequoia sempervirens), the redwoods here are only in small groves in very isolated pockets. Was it ever an extensive forest or was it always in isolated pockets?

Jim Sellers: The cones are falling after being cut down by the squirrel. The squirrel is so high in the canopy you can't see it. This is the time of year they are most active. To answer your question about the disjunct groves, it's an interesting genetic story. The giant sequoias were much more widespread previous to 4500 years ago and if you go back to 10 to 100 thousand years ago, there's a fossil record showing them in Florida and all across North America. As climates changed and the Sierra Nevada continued uplifting what apparently happened is the

Foundation Clonal Systems of Source Selection

Author: Dale E. Kester

PP: 318

INTRODUCTION

Plant breeding and plant propagation can be considered mirror images of one another. Plant breeding depends upon increased genetic variation to provide the chances of producing new cultivars. Plant propagation, on the other hand, depends upon decreasing, or at least controlling, genetic variation in order to maintain the genotype of specific cultivars produced by breeding. Maintaining plants that are true-to-variety and true-to-type is accomplished through selection of propagation sources. One of the primary methods of accomplishing this goal is through vegetative propagation and the selection of a clone. A further refinement of clonal selection and propagation is the selection of individual plants within that clone and will be referred to as foundation clones.

The purpose of this workshop is to describe the types of clonal variants that need to be controlled and the process utilized to achieve this control through "Foundation Clone" selection. These procedures are embodied

Foundation Plant Materials Service: Production and Distribution of Virus-tested Propagation Materials

Author: Michael L. Cunningham

PP: 323

INTRODUCTION

Foundation Plant Materials Service (FPMS), a unit of the University of California at Davis, was created to provide virus-tested plant materials for research and commercial use. Field- and greenhouse-grown plants of new varieties developed at the University, as well as plants from several unique collections from other sources, are maintained by FPMS on the Davis campus. Propagation material in the form of seed, buds, cuttings, rooted plants, and tissue-culture plantlets are supplied to the public. This service is in keeping with the University's policy to release healthy plant material whenever possible. Crops included in the FPMS programs include grapevines, deciduous fruit, and nut trees, roses, strawberries, and sweet potatoes.

Most of the material maintained and distributed by FPMS is propagated vegetatively. Although vegetative propagation has the advantage of creating progeny plants that are genetically identical to the mother, it also has the potential to

Seed Orchard Systems for Herbaceous Indigenous Wildflowers

Author: C. J. Delpratt

PP: 68

INTRODUCTION

One limitation to the large scale revegetation of the Australian landscape is a lack of suitable seed. To restore the diverse flowering grasslands and herbaceous understoreys typical of south eastern Australia, enormous quantities of seed will be required (Lunt, 1994). Revegetating with seed collected from nearby remnant plant communities helps ensure that local forms of species are preserved and that plants are well adapted to the prevailing environment. A risk is that seed collection activities may harm remnant areas. Damage can be from physical impacts, such as trampling, and biological impacts, such as over collection or the inadvertent introduction of weed seeds and diseases by collectors.

The cultivation of wild species for seed production has the potential to reduce collection pressure on remnant communities and to ensure that reliable supplies of quality seed are available when needed. If local adaptations are to be preserved, seed produced in cultivation

Nursery Propagation by Hardwood Cuttings: Prunus

Author: Thomas W. Burchell

PP: 327

Several tests were conducted to look at the rooting of Prunus hardwood cuttings in the commercial nursery. The commercial propagation of plum rootstocks (‘Marianna 2624’ and ‘Myrobaln 29C’) was used as a comparison with the more difficult-to-propagate rootstocks, ‘Hansen 536’and 1–82, peach/almond hybrids. A comparison between the size of the cuttings, the time of year they were cut, and the different environments in which they were grown was analyzed for two growing seasons (1994–95 and 1995–96).

Hardwood cuttings of ‘Hansen 536’ and 1–82 were cut in Nov. 1994 and Nov. through Feb. 1996 and either planted directly in the field or rooted in a greenhouse and then transplanted to the field. In 1995, plastic sleeves to cover the cuttings planted directly in the field greatly enhanced the survivability of the cuttings. Ninety-eight percent of the ‘Hansen 536’ cuttings that were covered with plastic sleeves rooted and survived in the field.

Hardwood cuttings of ‘Hansen 536’ were taken to the greenhouse in Feb. 1995. An overall rooting of 19% and a overall field survival of 75% was achieve that year.

In 1996, rooting of 10.2%, 4.1%, 11.1% and 9.2% occurred with hardwood ‘Hansen 536’ cuttings taken in Nov., Dec., Jan., and Feb., respectively. Different planting dates affected the survivability of the rooted cuttings the later on the winter the cuttings were planted, the better the survival. For example, only 10% of the cuttings planted in Jan. 1986 survive, were as 20% of the cuttings planted in April 1996 survived. This was also true in 1995 when 75% of the cuttings planted in April survived and grew well.

"Single Plant Selection as the basis for Foundation Clones" Question-Answer Period

Author:

PP: 333

Devin Cooper: Could you comment on the differences between the ‘Shirofugen’ and ELISA tests?

Mike Cunningham: The ‘Shirofugen’ index only works with Prunus necrotic ringspot and prune dwarf. ELISA will diagnose those, but it will also detect a whole range of leaf roll and fan leaf viruses in grapevines that Shirofugen is not sensitive to. ‘Shirofugen’ is not as specific as ELISA. When ELISA shows a positive result it indicates the presence of a specific antibody that is specific to a particular virus. ELISA is a 1- to 2-day project while ‘Shirofugen’ cherry is a 30-day project.

John Dixon: Why ‘Shirofugen’ over other cherries?

Mike Cunningham: I don't know. The ‘Shirofugen’ test was established by George Nyland several years ago. Apparently, there is something unique to ‘Shirofugen’ that is missing in other cherry genotypes.

Don Dillon: Do insect or other vectors pose a risk to reintroduction of viruses in your foundation planting and, if so, what can you do about it? Mike Cunningham: They do. Each crop

Recently Introduced Plants from Saratoga Horticultural Research Foundation and Techniques for Their Propagation

Author: Kathy Hesketh, Marlo Doherty

PP: 334

PLANT DESCRIPTIONS

Agapanthus ‘Storm Cloud’

The umbels, about 7 in. in diameter have tubular very deep blue-violet flowers that bloom mid-summer to early-fall and are borne on stalks 3 to 4 ft. high. The growth habit is similar to that of Agapanthus africanus, forming circular clumps 2 ft tall by 3 ft wide.

It is evergreen to 28F and in warmer areas can be used in mass plantings; in colder areas as color accents. ‘Storm Cloud’ does well in full sun to part shade although the flower stalks may be taller in sun and umbels larger in full sun. In hot environments ‘Storm Cloud’ should be placed where it is lightly shaded during the hottest part of the day.

It is an adaptable, easy care plant, preferring rich, moist, well drained soil although once established it is tolerant of drier conditions.

The original specimen of this plant was a seedling produced by Barrie Coate from the cultivar ‘Mood Indigo’, a hybrid developed by the Los Angeles State and County Arboretum by hybridizing A. afficanus

Potential Causes of Graft Incompatibility

Author: Frank S. Santamour Jr

PP: 339

There is probably no universal cause of graft incompatibility in woody plants. Anatomical, physiological, and biochemical factors may all play a part in this phenomenon. Scientific explanations of incompatibility in certain stock-scion combinations may have no relevance to other combinations. While intergeneric and interspecific graft incompatibilities may be more common and suggest that major differences based on phylogenetic evolution (and subsequent taxonomic classification) may be operable, graft incompatibilities between individual plants of the same species indicate that there are also more subtle forces at work. In this paper, the author presents and discusses some experimental data bearing on graft incompatibility as well as some suggestions for future research in this field.
Citrus Rootstock-Scion Compatibility and Characteristics

Author: Thomas Mulholland

PP: 343

HISTORY

The genus Citrus originated on the Asia continent, with tales of early movement from China, Burma, Malaysia, and Vietnam area to Mesopotamia and Palestine, sometime between the 9th and 6th Century B.C. The Biblical reference "hadar" suggests the citron to be the first citrus used, moved, and cultivated in new regions and by the Second Century the "Persian apple" was extensively distributed around the Mediterranean. During Constantine the Great (274–337 AD) mosaics of lemons and oranges were found. Albertus Magnus (1193–1280) described the sour orange with the name Arangus, the first description of C. aurantium, and later the term became the word orange.

Sometime in July 1518 citrus was planted in the Americas and it was during this time of expansion many new varieties were transported via seed.

Descriptions from travelers in Florida during the mid 1700s tell of citrus fruits growing spontaneously over the countryside. The majority of these trees were of the sour orange type. By the

"Graft Union and Incompatibility" Question-Answer Period

Author:

PP: 345

Jon LaForge: Steve, you mentioned a fungicide dip used in the field for Marianna. Could you explain that in more detail?

Steve Veyna: Sometimes we use Captan or Physan 20. We follow label directions to determine concentrations.

Frank Santamour: I forgot one word: predict. We can predict the incompatibilities without having made the graft on the basis of the isozymes for those species. I was talking about. Our predictions were 80% correct with the oaks.

Phil Barker: If a nursery wanted to identify the peroxidases in their material they are grafting, who could work with them?

Frank Santamour: Beautiful question, Phil. I investigated a nursery friendly home-design kit a number of years ago and it worked pretty well. But, this was done for human and animal blood work. When I tried to stain for peroxidases with this gel kit, it didn't work. For the price of postage, if it's real interesting, get in touch with me.

Jim Conner: A question for Steve Veyna… I had an opportunity to visit Bailey Nursery and

Antibiotics in Sphagnum Moss

Author: Charles E. Hess

PP: 347

Horticulturists have used sphagnum moss as a seed germination medium for years. It has a high moisture-holding capacity and provides good aeration. In addition to the favorable physical features, seedlings germinated in sphagnum moss have a lower incidence of "damping off," a term used to describe the rapid death of seedlings caused by several fungi including Pythium, Rhizoctonia, and Fusarium spp. Substances have been extracted from sphagnum which inhibit the growth of fungi associated with damping off. One source of the fungistatic substances is bacteria in the genus Pseudomonas which grow in association with sphagnum moss. The species of Pseudomonas producing inhibitory substances varied in sphagnum collected from different geographical areas. One of the substances is tropolone.
New Applications in Clonal Forestry

Author: W.J. Libby

PP: 350

DEFINITION

For many folks, clonal forestry simply means planting cloned trees in forests. However, it is increasingly coming to imply much more than that (Libby and Ahuja, 1993a). In brief, full clonal forestry means that a relatively few, tested, well-understood clones are deployed to the forest. Furthermore, it means that not only is the value of the forest increased because the clones have outstanding value, but also that the efficiency of management is increased because management can adapt to the strengths and requirements of each well-known clone.

Breeding Miniature and Other Roses

Author: Ralph S. Moore

PP: 355

Breeding miniature and other roses: To get to where you want to go, it's best to know where you are and where you have been.
Hardwood Cuttings as a Nursery Practice: Prunus, Developmental Aspects

Author: Dale E. Kester, Thomas Burchell

PP: 358

Hardwood cuttings are made of 1-year-old, dormant, leafless cuttings of deciduous plant species. For clones with a capacity to initiate adventitious roots easily, the procedure is simple, economical, and readily adapted to commercial applications. The development, introduction, and commercial success of a new nursery product, such as a clonal rootstock, is a long-term project which does not end in the research plot, but continues until the product is accepted by both the propagation nursery and the production industry. This paper describes a case history of one such product and ongoing stages in its development.
Vegetables, Heirlooms and Marketing

Author: William L. Ashburner

PP: 73

MEASURE OF DIVERSITY

The number of varieties of vegetables is a fair measure oftheir genetic diversity. The more distinct forms there are, the greater the genetic base of that type of vegetable. Any loss of varieties is an erosion of that diversity and the subsequent genetic potential of that type of vegetable. Some of the genetic diversity is present in the next generation of varieties, but unless the parents are maintained there is theoretically a potential for depletion of this diversity.

In 1903 the United States Department of Agriculture published American Varieties of Vegetables for the Years 1901 and 1902 which listed all available varieties. When this publication was compared recently with an inventory of the varieties held in the National Seed Storage Laboratory in Fort Collins, Colorado it was found that only 3% of these early varieties had survived to the present day (Whealy, 1987).

In 1985 the Seed Savers Exchange of Decorah, Iowa compiled and published a comprehensive

Rooting Walnut Hardwood Cuttings

Author: James R. McKenna, Ellen G. Sutter

PP: 362

INTRODUCTION

The use of hardwood cuttings is often the most economical method of producing clonal rootstocks or own-rooted varieties of temperate deciduous fruit trees (Hartmann, et al., 1990). Because leaves are absent and the material is dormant, hardwood cuttings are not as vulnerable to desiccation nor are they as cumbersome to handle as leafy semihardwood cuttings. These attributes make hardwood cuttings desirable for commercial nursery production.

Since walnut is difficult to root and genotypic variation in rooting ability exists, results derived from one clone may not be applicable to other clones. Significant differences in rooting ability among Juglans regia (Persian or English walnut), J. hindsii (northern California black walnut), and their F1, hybrid (J. hindsii ×J. regia) known as Paradox have been noted (Hartmann 1978). Paradox hybrids appear to have higher rooting percentages than either parent species. In addition, F1, hybrids differ markedly from BC1, (Paradox ×J

Propagation of Rose Rootstock ‘Doctor Huey’ from Hardwood Cuttings

Author: Bruce Frost

PP: 368

Bear Creek grows Jackson & Perkins and Armstrong brand cultivars of roses. We are located 20 miles north of Bakersfield, CA, near the southern end of the San Joaquin Valley. Most of our plants are budded onto one rootstock which we grow from hardwood cuttings. We plant approximately 17,000,000 hardwood cuttings each year and average 97% live cuttings stands. Our main rootstock is ‘Doctor Huey’, and we bud the selected cultivars onto that.

We start by fumigating our fields with methyl bromide in July or August and then prepare them for planting. The cuttings are collected from the 180 acres of stool blocks we maintain for cuttings source. We select cuttings that are mature enough that they won't bend easily, and are ¼ to 7/16 in. in diameter. Five crews made up of 10 people each, who follow a tractor and trailer through the stool block, gather canes 30 in. long and place them on the trailer where they are grouped into bunches of 50 and placed in a tube that has slots that allow for

Embryo Rescue and Genetic Transformation

Author: Richard Emershad

PP: 370

INTRODUCTION

A part of the plant breeding program at the USDA's Agricultural Research Service in Fresno is to develop early-ripening fresh market stone fruit and seedless grapes for the table and raisin industry. The California stone fruit industry needs earlier ripening cultivars which have fruit with good size, color, and eating qualities (i.e., high sugar and firm texture). For California's table and raisin grape industry early-, mid-and late-ripening seedless cultivars are needed with good fruit characteristics. Using conventional breeding the presence of immature embryos in early-ripening stone fruit and seedless grapes only allows their use as male parents. Therefore, in stone fruit, mid-season selections that develop mature seeds are used as female parents. For grapes, seeded females are used and only about 15% of the hybrid offspring are seedless. These small hybrid populations of early-ripening stone fruit and seedless grapes make the development of new cultivars slow and

Biology and Management of Crown Gall Disease in the Nursery

Author: Larry W. Moore

PP: 374

Crown gall disease occurs on over 390 genera of plants (Bradbury, 1986). It is most significant on plants grown for the nursery trade because galled plants are culled and discarded. Annual losses can run in the millions of dollars (Kennedy, 1980). The disease is particularly damaging to plants that become infected the first year after out-planting. Severely galled young plants are weakened, stunted, unproductive, and occasionally die. Contradictions abound, however, regarding the injurious effects of crown gall. Regardless, current nursery practices of culling galled plants is highly recommended as a means of providing clean planting stock.

Crown gall is a tumor disease of plants caused primarily by three pathogenic species of Agrobacterium: A. tumefaciens, A. rhizogenes, and A. vitis (Bouzar, 1994). Although this "new" classification is more correct than earlier classifications, it is confusing due to historical usage of A. tumefaciens to designate pathogens and A. radiobacter to

METHYL BROMIDE ALTERNATIVES FOR FIELD-GROWN NURSERY STOCK

Author: Michael V. McKenry

PP: 378

INTRODUCTION

It is through the purchase of contaminated nursery stock that new and different soil pests, diseases, nematodes, and viruses are most readily and widely distributed to farmers' lands. For California growers the nurseries have provided nematode-free field-grown nursery stock through the combination treatments of fallowing/soil fumigation. Today, California farmlands remain free of reniform nematode and burrowing nematode. The same cannot be said for growers in Florida, Texas or northern Mexico. Of the 300,000 ha of California stone fruits and almonds, some of which have now been replanted three or four times, only 33% are infested with Pratylenchus vulnus, the root lesion nematode. As new biotypes of root knot nematodes have broken the resistance mechanisms in Harmony and Freedom grape rootstocks that problem is clearly an in-field occurrence rather than a problem being transported along with nursery stock. The same can be said about biotypes of phylloxera on A.×R.#l (syn.

Growing with a Cravo Retract-a-Roof Greenhouse

Author: Thomas Fessler

PP: 382

At Woodburn Nursery and Azaleas the decision to build a retractable roof structure was easy once we had all the facts and costs. The number one thing we looked at was the cost of producing the plant. The question was asked how could we produce plants quicker and less expensively. We grow certain plants inside plastic covered houses, out in the full sun, under a shade or lathe house. Certain plants performed better under different conditions. The biggest problem we had was when Mother Nature prevented us from doing things when necessary thus creating production problems. This increased our expenses and jeopardized crop quality. Flexibility was an issue that was high on the priority list. The greenhouse had to be flexible for several different crops, with easy accessibility for moving product in and out of the structure. Labor that was needed to cover and uncover the greenhouse in the winter months was a big consideration. We needed a structure that required minimal labor because we were
Seed Collection and Cleaning Revisited

Author: Douglas Lee

PP: 383

The seed is sown. Adequate water is imbibed. Temperature is modulated. Soil-and water-born pathogens are controlled. Appropriate lighting is applied. Germination can then be expected to occur. These conditions assume one crucial element; the propagator has acquired and sown viable seed with adequate vigor. Increased mechanization, cost-consciousness, and competition in the nursery require the propagator to obtain quality viable seed. Seed must be, true to type, and free from waste, pathogens, and contaminates. As a seedsman, who has been involved in the collection and distribution of ornamental tree, shrub and palm seeds for over 23 years, I have acquired some practical expertise. The skill for this trade is learned through practice, education, apprenticeship, and trial and error. From where and how the seed travels from plant to propagator is the subject for discussion.
Seed Testing and Seed Dormancy

Author: Aleta Meyr

PP: 387

THE SEED TESTING LABORATORY

The job of the seed testing laboratory is to provide information about the quality of a given seed lot. The data reported by the lab is useful for initial cleaning, processing, and labeling as the seed moves into commercial channels.

The primary seed tests done by a certified seed laboratory are the germination or viability test, the physical purity test, seed counts, and the moisture content of the seed.

In the United States there are three main types of certified seed labs: Federal and State Labs, staffed by a member of A.O.S.A. (Association of Official Seed Analysts); company labs, staffed by a Registered Seed Technologist, member of S.C.S.T. (Society Commercial Seed Technologists); and an independent, private, commercial seed testing lab, staffed by an R.S.T. from S.C.S.T.

Seed testing in all three of the above labs is usually performed according to the Rules for Testing Seed put forth by the A.O.S.A. By testing the viability of seeds in paper media and

Seed Priming and Pelleting: Tools for Stand Establishment

Author: Cher Brandt

PP: 391

Seeds are pelleted for ease of handling, singulation, precision placement, and the incorporation of beneficial chemicals, such as fungicides or microbials. Cereal seeds were the first seeds to be pelleted in Europe. Sugar beets were one of the first seeds to be pelleted in U.S. The outlawing of the short-handled hoe for the lettuce industry created demand for coated lettuce seed as the use of precision field seeders increased. As well, the expansion of greenhouse-transplant production created another arena where pelleted seed would be a labor-saving device, for both vegetables and flowers.
Rose Breeding of the Future

Author: Keith W. Zary, John K. Walden

PP: 395

The fossil record dating back 35 million years, indicates that roses were widespread across the Northern Hemisphere. Roses have been a part of various cultures throughout the ages. The first systematic application of the science of breeding and selection to roses was begun in England in 1865. The U.S. Plant Patent Act of 1930 made it possible for breeders to receive revenues for their intellectual property, which in turn enabled them to expand their breeding of roses. The rose is probably the most intensively bred woody ornamental plant in the world. Still, rose breeders have been unable to develop resistance to black spot (Diplocarpon rosae), a primary objective. Breeders are looking at genetic engineering as a tool to advance germplasm to the point where breeders can utilize the immunity to black spot found in nature. Biogenetic firms and university researchers are currently exploring the techniques of transformation and regeneration(T-R) and the use of antisense technology, for the expression of new colors, disease resistance, fragrance, and improved shelf-life (cut flowers).