THURSDAY - FRIDAY Thursday, Oct. 2 · Morning–Board of Directors · Friday, Oct. 3 · Morning–Meetings–Workshop 1 Program Schedule 100th Annual International Conference of the American Society for Horticultural Science Providence, Rhode Island

8:00 am–10:00 am COMMITTEE MEETING 555A Thursday, October 2, 2003 Journal and HortScience Associate Editors Co-Chairs: Albert C. Purvis, Science Editor, ASHS Journal 7:30 am–4:30 pm Westin–Executive Board Room M. LeRon Robbins, Science Editor, HortScience ASHS Board of Directors Meeting 8:00 am–10:00 am WORKSHOP 1 555B Friday, October 3, 2003 Horticulture for the 21st Century: Developing International Collaborations 7:00 am–8:00 am BUSINESS MEETING 556A Moderator: Rolston St. Hilaire Moderator Training Session Sponsor: International Topics of Concern to Horticulture Working Presiding: Carl E. Sams Group (ITCH) Chair, ASHS Technical Program Committee Objective:The objective of this workshop is discuss ways to enhance the participation of international scientists in domestic meetings. 8:00 am–9:00 am COMMITTEE MEETING 554B Industry Advisory Council Summary: To broaden the frontiers of horticulture in the future, scientists should address both domestic and international issues Chair: Larry Knerr facing contemporary horticulture. Although coordinated interaction between domestic and international scientists could widen those 8:00 am–9:00 am COMMITTEE MEETING 554A frontiers, fewer international scientists are participating in domestic Graduate Student Activities Committee meetings. This workshop will explore ways to enhance the sharing of Chair: Essie Fallahi information among all scientists with the overall goal of improving the participation of international scientists in domestic meetings. 8:00 am–10:00 am COMMITTEE MEETING 550B Friday, October 3, 2003 Fellows Screening Committee Hours: Chair: Chien Yi Wang Registration (Ballroom A) 7:30 am–6:30 pm Speaker “Ready Room” (Room 550A) 7:00 am–6:30 pm 8:00 am–9:00 am COMMITTEE MEETING 556A Emeriti Lounge (Room 558B) 8:00 am–6:30 pm Working Group Chairs and Chairs-elect Placement Service (Room 553) 12:00 noon–6:00 pm Presiding: L. George Wilson E-mail Stations (Ballroom A) 12:00 noon–6:30 pm Poster Viewing (Ballroom A ) 12:00 noon–6:30 pm Exhibit Hall (Ballroom A) 12:00 noon–6:30 pm 8:00 am–10:00 am COMMITTEE MEETING 556B HortTechnology Associate Editors Friday Highlights Chair: Neal E. De Vos Opening Plenary Session (Ballroom B/C) 10:00 am–12 noon Includes: Pre-Conference Tours1 William A. “Tex” Frazier Lecture (Ballroom B/C) Awards Ceremony (follows William A. “Tex” Frazier lecture) Wednesday October 1, 2003 Colloquium 1 (Ballroom B/C) 1:30 pm–5:00 pm Tree Fruit Tour 8:00 am–5:00 pm Advance Registration is Required for: Thursday October 2, 2003 Student Mixer New England Vineyard & Winery Tour 7:30 am–7:00 pm (Westin-Newport/Washington Room 4:30 pm – 5:30 pm Greenhouse Production Tour 8:00 am–5:15 pm Welcome Reception & ASHS Endowment Fund Historic Boston 9:00 am–5:00 pm Raffle (Westin/Narragansett Ballroom) 6:30–8:00 pm Whale Watching 9:00 am–4:30 pm Tour1—Walking Tour of Providence 2:30 pm–4:15 pm 1All tours depart from the Sabin Street side of the Convention 1All tours depart from the Sabin Street side of the Convention Center. Center.

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The session will have two or three speakers and a panel discussion. activities. In each collaborative arrangement the political-economic Some topics that will be discussed include, funding opportunities conditions, cultural traditions and societal customs must be considered for international scientists willing to attend domestic meetings and in order to have effective and successful programs that will benefit mentoring foreign scientists through the publishing process. the people in both countries. Introduction International Volunteer Opportunities for Rolston St. Hilaire* U.S. Horticulturists” Department of Agronomy and Horticulture, New Mexico State Uni- Katie Rasmussen* versity, Las Cruces, NM 88003 Program Manager, Winrock International, Volunteer Technical As- American Foreign Aid Programs in Agriculture—Oppor- sistance Unit, 38 Winrock Drive, Morrilton, AR 72110 tunities for Technology, Knowledge and Skills Exchange For over ten years, Winrock International has provided opportuni- ties for U.S. citizens to share their skills and expertise with farmers and Kristina Gribovskaja* entrepreneurs in developing countries. Funded by the U.S. Agency for Program Coordinator, Citizens Network for Foreign Affairs, 1111 19th International Development (USAID), programs that utilize volunteer St., NW, Suite 900, Washington, DC 20036 technical assistance have provided immediate assistance to hundreds Foreign aid promotes freedom, security and opportunity and is in of businesses, farms, and producer organizations worldwide and have the national interest. As a result, U.S. official development assistance exposed Americans to other cultures and ways of life. Since 1991, (ODA) level is projected to increase from 9.9 billion US dollars in Winrock has completed over 2700 short-term (2-3 week) volunteer 2000 to 10.4 billion by 2004. From that pool of funding, 10.5 mil- assignments in Africa, Asia, Eastern Europe, the former USSR, lion dollars per year is currently available for the John Ogonowski and Latin America. U.S. horticulturists have provided assistance to Farmer-to-Farmer (FtF) Program. The FtF Program provides volun- orchard managers in Nigeria on integrated pest management, intro- tary technical assistance on a people-to-people basis and serves as duced non-traditional vegetable varieties in Uzbekistan, advised on an effective and flexible mechanism for exchanging and transferring apple orchard management in Nepal, and worked with foresters on technology, knowledge, and skills of volunteer U.S. agriculturalists pest management for fruit and nut trees in Kyrgyzstan. Volunteer to individual farm enterprises, cooperatives, farmers· associations, assignments often result in further collaboration between U.S. and agribusinesses, rural credit institutions, universities, and agricultural host country universities, professional associations, and businesses, youth groups. Often, partnerships develop between host country or- and provide an excellent opportunity for U.S. horticulturists to share ganizations and U.S. organizations. Volunteer assistance is provided their knowledge and learn how horticultural production is approached in horticulture and many other agricultural disciplines. In general, in different parts of the world. FtF volunteers are not overseas development professionals, but rather farmers, extension agents, university professors, private consultants, 8:00 am–10:00 am WORKSHOP 2 552A and association/cooperative staff. In the worldwide FtF Program, almost 2,000 volunteer assignments have been completed between Nursery Irrigation Management: “Water Reckonings” 1991 and 1999 in more than 70 countries. In the NIS Program (New Independent States of the former Soviet Union), more than 3,700 as- Moderator: Hannah Mathers signments were completed between 1992 and 1999. The FtF Program Sponsor: Nursery Crops (NUR) funding has been contractually distributed among five implementers – Partners of the Americas, Winrock International, ACDI/VOCA, Objective: To increase awareness of recent restrictions in water use Land O·Lakes, and CNFA. This presentation will detail ways to and runoff facing the industry and how gains in irrigation manage- participate in the FtF Program. ment can increase water use efficiencies. Developing International Collaborations in Central and Summary: Freshwater resources are being depleted throughout the Eastern Europe world and many states have imposed restrictions on water use and runoff and/or nutrient runoff from agricultural operations, including Alexander A. Csizinszky* nurseries. Nursery operations are perceived as “water wasters”. This University of Florida, Gulf Coast Research and Education Center, session will outline how and why “status quo” water management th 5007 60 Street East, Bradenton, FL 34203 is no longer good enough. Economic systems in the former soviet bloc countries of Central and Eastern Europe are in the process of moving from state-owned, Overview of Nursery Irrigation Management centrally planned and directed socialized systems to market-oriented Hannah Mathers* private enterprises. As a result, people, especially in the agricultural Dept. of Horticulture and Crop Science, Ohio State University, Co- sector, face major problems during the transition period since there is lumbus, OH 43210-1096 no precedence anywhere about the transition from a centrally planned and directed system to a market-driven economy. The major problem We are positioned in an environmentally oriented sector. The is t hat the countries do not have experts in educational institutions nursery industry manufactures of the “tools” that naturally clean up and in government agencies who have knowledge and experience and maintain a healthy environment. As water becomes scarcer and in the organization, finance and management of private enterprises. water quality issues intensify, future restrictions on water use are im- Furthermore, many of the countries lack the institutions that can handle minent. Status quo water management in nursery is no longer good financial and technical aid from western countries in an effective and enough! The efficiency of any irrigation system consists of three timely manner. In spite of the difficulties, there are several examples of elements, application efficiency, distribution pattern efficiency or successful cooperative arrangements among government financed edu- distribution uniformity (DU) and combined application efficiency. cational institutions and non-governmental agencies from the western The application efficiency is determined by comparing the amount countries to exchange academic, business and technical personnel from of water stored in the root zone of the plant compared to the total Central and Eastern Europe. The emphases in these cooperative and amount of water delivered to the site. The current status of the indus- exchange programs are on, but not limited to, sustainable agriculture try regarding irrigation efficiency and what are some ways current and resource management, marketing methods, financial planning, research indicates nursery growers can reduce water use in nursery food safety, and involvement of women in agricultural and societal culture will be emphasized.

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Implications of Water Use Restrictions for Container Wilbur Reil, Larry Schwankl, Beth Teviotdale. Mario Viveros FRIDAY am Plant Producers Dept. of Pomology, University of California Thomas H. Yeager* Research over several decades has shown potential benefits of University of Florida deficit irrigation in almond at certain times during the season. A period of moderate deficit irrigation during the hull-split period in almond More Plant Per Gallon: Getting More Out of Your Water can result in decreased hull-rot, a common disease caused by Rhizo- Stuart Warren* pus Stolonifer, Monolinia fructicola or Monolinia laxa. The strategy North Carolina State University involves maintaining baseline midday stem water potentials of -7 to -9 bars before and after hull-split and a -14 to -18 bar midday stem water Modeling Irrigation Requirements for Landscape potential during hull split followed by a full watering regime after hull- Ornamentals split. In an ongoing hull-rot trial with sites in seven areas in the state of California, this technique has been shown to result in significant water Richard C. Beeson, Jr.* savings and no significant impacts on nut size or overall yield. At sites University of Florida, Institute of Food and Agricultural Sciences, where hull rot was a problem in the past year of the study, the hull-rot Mid-Florida Research and Education Center, 2725 S. Binion Rd., deficit treatment resulted in a significant decrease in hull-rot strikes per Apopka, FL. 32703 tree. Previous and ongoing work has shown that negative impacts of In many sectors of agriculture, precision irrigation has become a mild to moderate deficit irrigation on yield in almond is primarily due familiar term. However, irrigation in most woody ornamental nurseries to reduction in canopy volume. Therefore, deficit irrigation strategies has changed little since the 1960·s. In many areas of the US, irrigation that are imposed after the desired canopy volume is reached may be volumes required for nursery production have come under scrutiny due more likely to result in effective hull rot management with less chance to projected, or real, competition for water with urban populations, or for negative impacts on yields. Irrigation and nitrogen management concerns over nursery run-off. Modeling of woody ornamental water impacts spur longevity and the relevance of this to deficit irrigation use, and subsequent irrigation requirements has been limited. Previous management will also be discussed. research for modeling of non-tree water use will be briefly reviewed as an introduction to current efforts to develop models for precision Irrigation Management for California Walnut irrigation of woody ornamentals. Pitfalls and limitations in current Richard Buchner*1, Allan E. Fulton and Ken A. Shackel modeling efforts, along with suggestions for standardizing future 1Univ. of California Cooperative Extension research will be emphasized. Models based on recent years· research Amature walnut orchard transpires an enormous amount of water. will be presented. Conditions vary, however, in California most walnut orchards have Blue-Skying Clear Water in Nursery Crop Production the potential to evaporate approximately 42 acre-inches of water per acre, annually. Since there is little or no effective rainfall during the James L. Green* growing season and winter soil moisture storage is inadequate, nearly Department of Horticulture, Oregon State University, Corvallis, OR all California walnut acreage is irrigated. Flood irrigation, under-tree 97331-7304 sprinklers or micro-sprinklers are all successfully used for irrigating Blue-skying refers to strategic planning, brain-storming, free-wheel- California walnuts. Many ways exist to help farmers decide when ing, dreaming, and asking “Why not?” We will look at the quantities to irrigate and how much water to apply. Soil moisture monitoring, of fertilizer nutrients and water a plant consumes during a growing using tensiometers, moisture blocks, neutron probe or capacitance season and at evolution of production systems to more closely match techniques have been in use for a long time. The difficulty is: knowing application with consumption. We will consider a proposed controlled the measurement locations and sampling depths actually represent environment production system that utilizes only 10% or less of the the orchard; correctly defining the range in plant available water for energy and environmental inputs of current greenhouse systems. We will variable soils so that management thresholds can be appropriately set; synthesize a potential future production system where the plant can: 1) and assuring equipment calibration is accurate. Another technique is govern uptake of water into the root substrate, 2) govern solubilization the water balance or budget approach. Regional weather conditions and uptake of fertilizers from protected reservoirs, and 3) generate pure are used in predictive models along with specific crop coefficients to water through evaporation, transpiration and condensation and conserve estimate real-time plant water use or evapotranspiration (ET). These solar energy via conversion to latent heat energy. estimates can be easily related to pressurized irrigation system designs to guide when to irrigate and how long to run the irrigation system. 8:00 am–10:00 am WORKSHOP 3 551B Particularly with flood irrigation, a reliable estimate of stored soil moisture is important to successfully apply the water budget approach. Irrigation Strategies for Temperate Tree Nut Crops Water budgeting cannot account for site-specific conditions such as orchard health and tree age which may affect crop water demand. Moderator: Patrick J. Conner Using the water balance approach also assumes that even mild levels Working Group Sponsor: Temperate Tree Nut Crops (NUTS) of crop stress are undesirable and may result in missed opportunities to reduce irrigation costs and realize potential horticultural benefits. Objective:To discuss and evaluate current strategies in the applica- Plant based methods to measure orchard water status are increasing tion of water to temperate nut crops. in popularity. One technique for walnuts is to use a pressure chamber Summary: Urban growth, regional droughts, and agricultural de- or “bomb” to measure stem water potential (SWP). Measurements are velopment have resulted in increased demand for fresh water. This taken mid-day (12 pm – 4 pm) when trees are experiencing maximum workshop will evaluate the irrigation systems in almond, pistachio, evaporative demand. Leaves are placed inside water impervious, light and walnut orchards. Experts in each of the crops will present the blocking foil bags for roughly 10 minutes. During the 10 minute inter- val leaves equilibrate with the stem xylem tension. After equilibrium, systems used and discussions will evaluate the strengths and weak- bagged leaves are placed into the pressure chamber and stem water nesses of each. potential is measured. Pressure chambers have been used for a long Deficit Irrigation Management for Almonds time in a variety of crops to detect leaf water potential and predawn leaf water potential, however, using mid afternoon SWP for irrigation Bruce D. Lampinen*, Kenneth A. Shackel, Dave Goldhamer, scheduling in walnuts is a new application. The initial investment in Rick Buchner, Joe Connell, John Edstrom, Allan Fulton, equipment is relatively expensive, measurements are restricted to Brent Holtz, Bill Krueger, Samuel Metcalf, Terry Prichard, midday when evaporative demand is highest, and it·s not completely

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clear how to interpret measured values. However, applied research ous strawberry cultivars planted in early, mid and late October. This is underway to clarify interpretation of midday SWP in walnut and experiment was conducted for 3 years (1999, 2000, 2002). Six cultivars develop management strategies based upon plant-based measurements (Chandler, Gemstar, Camerosa, Gaviota, Treasure, and Bish) were of orchard water status. grown from runner tips in TLC 50 plug trays for six weeks prior to the first field planting. Field planting dates were October 10, 20, 30. Effect of Irrigation on the Yield Components of Pistachio All plugs were started on the same day, yet plugs for the second and Bob Beede* third plantings were older at field planting. Plants were grown on Univ. of California Cooperative Extension raised bed, twin rows (12” by 12”), ten plants per treatment. Berries were harvested at full maturity and graded according to U.S. standards. 8:00 am–10:00 am ORAL SESSION 1 557 After the final harvest all plants were dug and crowns counted. The trends in the data suggest that the first planting date produced exces- Viticulture and Small Fruit-Culture and Management sive crown development resulting in greater production of undersized Moderator: Fumiomi Takeda berries. Plants excavated from the last planting date had fewer crowns and yield larger berries, but yields were reduced. Plants from the 8:00 Plant Density Affects Fruit Yield and Quality of Green- Oct 20th planting date had six to eight crowns per plant that yielded house Strawberry Grown in Pinebark Under Pesticide-free high numbers of high quality fruit of excellent size and shape, but Conditions cultivars responded differently depending on the years as well as the Ashwin Paranjpe*1, Daniel Cantliffe1, Elizabeth Lamb2, fall transplanting dates. Peter Stoffella2, Charles Powell3 1Horticultural Sciences, University of Florida, 1143 Fifield Hall, Gaines- 8:30 Environmental Impacts of Cold-climate Strawberry Pro- ville, Florida, 32611-0690, 2Horticultural Sciences, IFAS Indian River duction Systems Research and Education Center, 2199 South Rock Road, Ft. Pierce, Matthew D. Stevens*1, Brent L. Black2, John D. Lea-Cox1, 3 Florida, 34945, Plant Pathology, IFAS Indian River Research and Cathleen J. Hapeman3 Education Center, 2199 South Rock Road, Ft. Pierce, Florida 34945 1NRSL Department, University of Maryland, Plant Science Building, Strawberry (Fragaria ×ananassaDuch.) production in greenhouses College Park, MD, 20742, 2Fruit Laboratory, USDA-ARS, Beltsville using soilless substrates can eliminate dependency on methyl bromide Agricultural Research Center, Beltsville, MD, 20705, 3Environmen- and enhance off-season production. In Fall 2001, eight plant densities tal Quality Laboratory, USDA-ARS, Beltsville Agricultural Research (10.8 to 22 plants per m2) and in Fall 2002, twelve plant densities (10.8 Center, Beltsville, MD, 20705 to 27.5 plants per m2) of ‘Sweet Charlie· strawberry were evaluated fi for fruit yield and quality using six between-row spacings (BRS) (65, Replicated eld plots of three mid-Atlantic strawberry production 60, 55, 50, 45, and 40 cm) and two within-row spacings (WRS) (35 systems, conventional matted row, advanced matted row, and cold- and 17.5 cm). Plants were grown in a passive-ventilated greenhouse climate annual hill plasticulture, were established in Beltsville, MD in in north-central Florida using elevated horizontal troughs filled with 2002 for comparing environmental impacts. The conventional matted pinebark. In Fall 2001, the early and total yield per m2increased linearly row system commonly practiced in the mid-Atlantic region involves for all combinations of BRS and WRS as plant density increased. In overhead irrigation, spring and fall banded fertilizer applications, and Fall 2002, the early and total yield per m2 increased as BRS decreased cultivation for weed control. The cold-climate plasticulture system is from 65 cm to 45 cm, however, there was a reduction in yield at 40 similar to that used in North Carolina and involves raised beds with cm BRS. Also, yields per m2 were higher at 17.5 cm WRS compared plastic mulch, drip irrigation, and fertilizer injected into the drip system to 35 cm WRS. During both seasons, the average berry weight ranged at weekly intervals. The advanced matted row system developed at from 17 to 20 g, and more than 90 percent of the yield was market- the USDA research station in Beltsville, MD includes raised beds able. During Fall 2001, limited success was achieved when biological with drip irrigation, weekly fertigation, and utilizes a cover crop control agents such as Aphidius colemani and Lysiphlebus testaceipes residue mulch and directed herbicide application for weed control. parasitic wasps, and Neosiulus californicus predatory mites were used Each system was established in three replicate 6 ×15 m plots and in conjunction with chemical insecticides for controlling aphids (Aphis managed according to commercial standard practices for the region. gossypii) and two-spotted spider mites (Tetranichus urticae). However, Each plot was equipped for measuring and sampling surface runoff, during Fall 2002, exclusive use of biological control agents resulted and for sampling ground water. During the 2002 establishment year, in 95 percent aphid parasitism by parasitic wasps within six weeks of samples were collected from 18 rainfall events, and irrigation use was release and 100 percent control of two-spotted spider mites by preven- recorded weekly. Averaged over rain events, soil loss in runoff water tive monthly releases of predatory mites. Thus, high plant densities was 19.5±7.9, 11.5±4.5 and 2.9±0.7 kg/ha for conventional matted affect fruit yield and quality of greenhouse-grown strawberries and row, plasticulture, and advanced matted row, respectively. Irrigation enhance off-season production, and effective biological control agents water requirements were 50% less in the advanced matted row than offer a unique opportunity for producing pesticide-free strawberries in the conventional matted row system. Nitrogen leaching and runoff and increase the dollar value of the product. varied over the course of the year based on the timing of fertilizer application. Parameters for comparing the economic viability of each system were also measured. 8:15 Fall Transplanting Dates Affect Overall Performance of Strawberry Cultivars 8:45 Cover Crop Alternatives for Strawberry Replant Pre- Richard Hassell*, Tyron Phillips paration Plant and Environmental Science, Clemson University, Coastal Re- Ann Seigies*1, Marvin Pritts2 search and Extension Center, 2865 Savannah Highway, Charleston, 1 South Carolina, 29414 Department of Horticulture, Cornell University, 161 Plant Science Bldg, Dept of Horticulture, Cornell University, Ithaca, NY, 14853, In coastal South Carolina, spring-harvested strawberry plugs are 2Horticulture, Cornell University, 134A Plant Science Bldg, Cornell normally transplanted sometime in October. It is unknown, how- University, Ithaca, NY, 14853 ever, whether early October planting dates are superior to later dates in crown growth and development, earliness, total yield and quality In strawberry (Fragaria ×ananassa) and other cropping systems, in subsequent spring harvests. The objective of this research is to the use of certain cover crops has shown promise in suppressing soil determine the variation in growth and yield characteristics of vari- borne pathogens, and has the potential to replace methyl bromide fumigation. Black root rot (BRR) of strawberry is a common replant

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disease caused by a complex of soil inhabiting organisms. Fields of 9:15 Effects of Windborne Deicing Salts on Highbush Blueberry FRIDAY am strawberry infected with BRR experience short-life and markedly (Vaccinium corymbosum L.) lower yields. We hypothesized that certain preplant cover crop rota- Steven Berkheimer*, Eric Hanson, James Hancock tions would reduce the occurrence of BRR in strawberry plantings, and, likewise, increase fruit yield and plant vigor. To test this, four Horticulture, Michigan State University, Plant and Soil Science Bldg, replicates of the following treatments were established in a RCBD East Lansing, MI, 48824 in 1999: mowed weedy fallow, continuous strawberry, and methyl This work was conducted to determine if flower bud and twig bromide (plus chloropicrin) fumigation. Cover crop treatments con- mortality observed in blueberry fields adjacent to Michigan highways sisted of perennial alfalfa; a rotation of kale (Fall 1999) followed by was the result of wind-blown deicing salts (primarily NaCl). Flower sweet corn (Summer 2000) ending with rye (Fall 2000); a rotation bud mortality and salt deposition were recorded on 10 farms. The of hairy vetch, marigold and rye; a rotation of oats, sudangrass and most severe injury and highest salt levels were observed closest to rye; and three consecutive rotations of mustard. Each treatment was heavily traveled roads. Spraying potted blueberry bushes 6 times followed with strawberry cv. Jewel, planted in May 2001. Results from during the winter with NaCl solutions (0, 2, 4, 8,16 and 32g/L) the study show that fruit yield and plant biomass were significantly caused the same type of injury observed in roadside fields, and the improved under all treatments compared with continuous strawberry, severity was proportional to the NaCl concentration. The root media with the highest marketable yield in the mustard treatment and the of other potted plants was saturated with NaCl solutions (0, 1, 3, 9 greatest biomass in the fumigated treatment. The continuous straw- and 27g/L) in March then rinsed with distilled water in April at bud berry treatment produced the weakest root systems with a moderate swell to determine if elevated soil salt levels would cause similar rate of infection, and the fumigated treatment produced moderate damage. The highest soil salt levels killed most above ground growth, root systems with a lower rate of infection. In this study, a mustard but these soil levels were much higher than those observed in soils rotation seemed to improve a BRR-infested soil more than other sampled close to affected fields, suggesting that field injury was the cover crop rotations. result of salt deposition on buds and twigs rather than elevated soil salt. Twigs were also excised from salt treated and control branches and frozen incrementally to determine the temperature killing 50% 9:00 Soil Amendment with Hydrophobic Kaolin Particles of flower primordia (LT50). The LT50 of salt treated flower buds was Reduce Weeds as much as 11 °C higher than those receiving no salt. Fumiomi Takeda*1, D.M. Glenn2, Thomas Tworkoski2 1USDA-ARS, Appalachian Fruit Research Station, 45 Wiltshire Road, 9:30 Evaluation of the Leaf Boron Standard for Vaccinium 2 Kearneysville, WV, 25430, Appalachian Fruit Research Station, angustifolium Ait. USDA-ARS, 45 Wiltshire Road, Kearneysville, WV, 25430 John Smagula*1, Karen Loennecker2 Experiments were performed to suppress weed seed germination 1 by amending soil surface layer with a hydrophobic kaolin particle Plant, Soil, and Environmental Sciences, Univ. of Maine, 416 Deering 2 (M96-018, Engelhard Corp.). In the first study, a field that was in Hall, Orono, ME, 04469-5722, Plant, Soil, and Environmental Sciences, permanent pasture the previous 5 years was rototilled and 1-m2 plots of Univ. of Maine, 415 Deering Hall, Orono, ME, 04469-5722 untreated and treated soil were established in a pair-t-test design with Soil-applied Granubor (14.3% B) at 2.24 kg B/ha and foliar-ap- 6 replications. In the treated soil, M96-018 kaolin was incorporated plied Solubor (20.5%) at 0.74 kg B/ha, applied with or without DAP uniformly into the upper 3-cm of soil with hand cultivation in August. (448 kg/ha), was compared to a control and to DAP without B. DAP The concentration of M96-018 kaolin was 3% by weight in the treated and soil-applied B were applied preemergent and foliar-applied B in soil. Following spring, a circular area of 0.12 m2 was sampled in the mid June 2001 to 1.5 m ×15 m treatment plots in a RCB design with 7 center of each plot. Dry mass of vegetation in the untreated treatment blocks. Crop-year plots (2002) were split, half receiving 0.74 kg B/ha was 219 g/m2 and was significantly higher (P = 0.05) than the 24 g/m2 from Solubor. Fruit set for 20 tagged stems/subplot was measured. harvested from the treated soil. In the second experiment, ‘Apache· Leaf B concentrations were below the 24 ppm standard in control blackberry container plants were planted through 900-cm2 square plots and were raised to sufficiency levels by both soil-applied B and openings spaced 75 cm apart in woven fabric weed barrier covering foliar-applied B, but had no effect on stem length, branching, flower a raised bed. The square openings were either mulched with a 2- or bud formation, fruit set or yield. Crop-year B application raised leaf 4-cm layer of M96-018 kaolin (5% in dry field soil by volume) or B but had no effect on fruit set. DAP, with or without B, raised leaf N treated post-plant with napropamide (Devrinol 50 DP at 5 gm/L). and P concentrations, stem length, and yield. Raising leaf B levels to The other two treatments in this study were mechanical weeding at above 24 ppm did not increase fruit set or yield in this and previous 2-week intervals and untreated control. At monthly intervals during studies and suggests that the standard for B is too high. the growing season, weed coverage was determined and weed species were identified, counted, and removed. The following weeds were 9:45 Effect of Phototrophic Condition on In Vitro and Ex Vitro dominant: smooth crabgrass (Digitaria ischaemum), lambsquarter Growth of ‘Campbell Early· Grape (Vitis hybrid) (Chenopodium album), ground ivy (Glechoma hedaracea), dandelion * (Taraxacum officinale), spurge (Euphobiasp.), pigweed (Amaranthus Jae-Hyuk Park, In-Chang Son, Seon-Kyu Kim sp.), chickweed (Stellaria media), and nightshade (Solanum sp.). By Department of Horticulture, Chungbuk National University, Gaeshin- end of July, untreated plots had 100% weed cover while mechanical dong San48, Cheongju, Chungbuk, 361-763, Republic of Korea weeding plots had the following soil surface area covered with weeds: Effect of phototrophic condition on in vitro and ex vitro growth 74% in June, 27% in July, and 10% in August. In plots treated with of ‘Campbell Early· grape was examined. Plant growth and plant napropamide or mulched with 5% M96-018 kaolin only 15 and 3 fresh and dry weight were better in photomixotrophic condition than weed seedlings were pulled during the establishment year and weed photoautotrophic or heterotrophic condition, while root growth was canopy coverage was less than 3%. These data showed that when favored with heterotrophic or photomixotrophic condition. CO2-enrich- soil is amended with hydrophobic particles, seed germination in the ment increased the chlorophyll content (a, b, a+b), survival rate, and amended zone is inhibited due to reduced availability of water in the fresh and dry weight. Ex vitro growth of photomixotrophically grown amended zone. Seed germination may occur at the amended soil-natural plantlets was much better than those grown under photoautotrophic or soil interface and a few weeds grew through a shallow, but not deep heterotrophic condition. CO2 uptake, stomatal conductance, transpira- layer of soil amended with M96-018 kaolin. Effects of kaolin soil tion rate, and maximum photochemical efficiency (Fv/Fm) of plants amendment on blackberry growth will be discussed. grown under photomixotrophic or photoautotrophic condition were increased during acclimation. Leaf sucrose and starch content of plants

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grown under photomixotrophic or photoautotrophic condition showed 9:00 Irrigation Timing Affects Fresh Cabbage (Brassica Oleracea a gradual increase till 15 days of acclimation, then slightly fluctuated L. Capitata Group) Sensory Quality fi with the new lea ng. Theodore J.K. Radovich*1, Matthew D. Kleinhenz1, Jeannine F. Delwiche2, Rachel E. Liggett2 8:30 am–9:45 am ORAL SESSION 2 552B 1Horticulture and Crop Science, The Ohio State University, Ohio Ag- Vegetable Crops Management-Culture/Management ricultural Research and Development Center, 1680 Madison Avenue, Practices, Product Yield and Quality Wooster, Ohio, 44691, 2Food Science and Technology, The Ohio State University, 2015 Fyffe Court, Columbus, Ohio, 43210 Moderator: Robert Dufault Flavor is a primary indicator of fresh market cabbage sensory 8:30 Influence of Plant Density on Yield and Quality of Green- quality. However, the influence of important management practices, house Galia Muskmelons Grown in Perlite including irrigation, remains unknown. Therefore, recent tests were Juan Rodriguez1, Daniel Cantliffe2, Nicole Shaw* completed to determine: 1) if irrigation alone influences the perception of fresh cabbage sensory quality and 2) whether the plant develop- 1Horticultural Sciences, University of Florida, 1251 Fifield Hall, PO box mental period during which irrigation is applied influences human 110690, Gainesville, FL, Gainesville, FL, 32611-0690, 2Horticultural differentiation between samples. The study was also designed to help Sciences, University of Florida, 1251 Fifield Hall, PO Box 110690, assess the relative sensitivity of cabbage physical and sensory traits to Gainesville, FL, 32611-0690 irrigation. In 2002, a replicated triangle test was employed to determine Production of high value crops in passive ventilated greenhouses in if judges could distinguish, by flavor, between shredded, undressed Florida is an efficient way to achieve high yields and high quality. In ex- samples of fresh cabbage (‘Bravo·) grown at the Ohio Agricultural periments conducted at the University of Florida Protected Agricultural Research and Development Center, Wooster, Ohio and drip-irrigated Project in Gainesville, Fla., yields of crops such as Galia muskmelons during different periods of development. Irrigation was provided to (Cucumis melo L) are generally three or more times greater than those replicated plots (RCB design) either: 1) throughout plant development fi obtained under eld conditions (Cantliffe et al., 2000; Waldo, 1999,). (no stress, NS), 2) during frame development only (head stress, HS), The use of soilless culture and adequate plant spacing that makes ef- or 3) during head development only (frame stress, FS). Control plants fi cient use of available greenhouse space, may result in higher yields received no irrigation for the duration of plant development (frame and that do not diminish marketable fruit quality. Experiments to evalu- head stress, FHS). In a total of three sessions at the OARDC Sensory ate the effects of four different plant densities (1.7, 2.5, 3.3, and 4.1 Evaluation Laboratory in October 2002, fourteen judges evaluated 2 plants/m ) on yield and quality of Galia-type (Gal-152) muskmelon two replications each of the six possible treatment comparisons in were conducted in Fall 2001 and Spring 2002 inside a double layer triangle tests. Results were analyzed using the beta-binomial model. polyethylene passive-ventilated greenhouse. Plant density did not have Judges were able to detect differences (_ = 0.05) between heads from an effect on early or total number of fruit per plant, but did affect yields NS plots and cabbage from the two plots that received no irrigation 2 per unit area and in the case of the 4.1 plants/m treatment, the aver- during head development (HS, FHS), as well as between heads from age weight per fruits. Yields per square meter had a linear response to FS and FHS plots. Therefore, attempts to manipulate flavor through plant density, where in yields per unit area increased with increased irrigation may benefit from focusing on soil moisture availability plant density. Higher yields were obtained in spring compared to fall, during head initiation and development. Flavor differences were but fruit quality, expressed as soluble solids content did not change, attributed in part to related differences in percent tissue moisture, regardless of the season or density treatments. Yield and fruit size can although more focused investigations into the chemical basis for fl 2 be in uenced by high plant densities. While the 4.1 plants/m treatment these differences are underway. Head weight, mean diameter and lead to greater yield but smaller marketable fruit size. shape at harvest were also affected by irrigation treatment. This is the first report of an effect of drip irrigation application and timing 8:45 Influence of Stand Density and Harvest Date on Grade on the flavor of fresh cabbage. The data also suggest that cabbage Distribution of Sweetpotatoes Grown on Heavy, Fertile head physical traits may respond more frequently to irrigation than Soils cabbage flavor attributes. Peter J. Dittmar*, Bradley H. Taylor, S. Alan Walters Dept. Plant, Soil, and Gen. Agric., Southern Illinois University, 1205 9:15 Harvest Pressure Affects Yield and Root Carbohydrate Lincoln Dr., Rm. 176 Ag. Bldg., Carbondale, Illinois, 62901-4415 Status of Spring-harvested and Summer-forced Asparagus The effect of planting density and harvest date on the yield and Robert Dufault*, Brian Ward grade distribution of sweetpotato roots were measured in a split plot Dept. of Horticulture, Clemson University, Coastal REC, 2865 Savan- experiment arranged in a randomized, complete block design with 3 nah Hwy, Charleston, South Carolina, 29414 replications. Main plots were four harvest dates (1, 14, and 28 Sept. ‘Jersey Gem· asparagus, planted in 1997, was harvested for four and 12 Oct.) using 1, 2 or 3 rows per 91 cm wide raised beds (1x, years beginning in 1999 at mild to heavy pressures in the spring or 2x, and 3x standard density) as sub-plots. ‘Beauregard· plants were forced in the summer beginning in August. Cutting pressures in both planted on 15 June at the Horticulture Research Center at Southern harvest seasons incrementally increased each year ranging from 14 fi Illinois University, Carbondale. Compared to the yield at rst harvest to 28 harvests (1st year), 19 to 33 (2nd ), 28 to 56 (3rd) and 42 to 70 date (6938 kg per ha), delaying harvest increased yields of U.S. No.1 (4th year). Asparagus was harvested daily including weekends and roots by 55%, 70%, and 110% for the 14 Sept., 28 Sept., and 12 Oct. root samples were collected monthly for fructose content over the harvests, respectively. Jumbo yields remained about one third of No.1 4 years. Spring-harvested treatments were not summer-forced and yields regardless of harvest date. Increasing from 1x to 2x or 3x visa versa. Spring-harvested yields increased linearly from the 2nd standard density, increased the yield of No.1 roots by approximately to the 4th year and as cutting pressures increased, marketable and 50%. The proportion of jumbo to US No.1 roots decreased from 83% cull yields increased. Summer-forced yields increased linearly for in the standard 1x density to 33% and 14% in the 2x and 3x densi- the first 3 years; however, by the 4th year, yields declined after me- ties, respectively. These results suggest that increasing the density of dium to high cutting pressure, but plateaued at low cutting pressure. sweetpotato plantings increases marketable yields for growers utilizing High cutting pressures are beneficial to maximize spring-harvested heavy, fertile soils in the variable precipitation pattern of the lower asparagus and, apparently, higher cutting pressures than evaluated midwest where harvest delay is common. would have been tolerable and may have increased yields further. In contrast, summer-forced asparagus can only tolerate low cutting

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pressure intensities. Root carbohydrate dynamics of the spring 10:00 am–12:00 noon Ballroom B/C high pressure and summer low pressure systems followed similar OPENING PLENARY SESSION patterns over the years, yet summer-forcing at medium to high cut- ting pressures depressed carbohydrate balance progressively over the Presiding: L. George Wilson years which may explain yield suppressions. ASHS President 16th WILLIAM A. “TEX” FRAZIER LECTURE 9:30 AComparison of Transgenic Bt and Non-transgenic Sweet Corn Varieties With and Without Irrigation Sponsored by Seminis Vegetable Seeds Rao Mentreddy*, Anand Yadav Horticulture, Horticultural Science, and Agricultural Research Station, Fort Valley State University, 1005, 100 Years of ASHS State University Drive, Fort Valley, Georgia, 31030 Jules Janick, Purdue University Genetically modified, insect protected sweet corn varieties with Bt (Bacillus thuringiensis) gene provide effective, consistent, and The ASHS Board of Directors is delighted to announce that Jules economic control of major sweet corn insect pests better than insec- Janick is the Tex Frazier Lecturer for our Centennial Conference ticides. Sweet corn yields have increased since the introduction of Janick·s presentation will include a review of horticulture and hor- transgenic Bt corn varieties, particularly under high insect pressure, ticultural science, with emphasis on the last 100 years. resulting in significant economic benefit to the farmer. The performance The Tex Frazier Lecture series was named in honor of William of transgenic Bt sweet corn relative to non-transgenic varieties under A. “Tex” Frazier, an eminent member of the faculty at Oregon State variable irrigation levels has not been reported. Thus, in a field study University. The intent of the lecture series is: “to foster and promote conducted at three locations, a transgenic Bt sweet corn variety ‘GSS reciprocal liaisons between ASHS and other professional groups; 0966·having Bt Cry 1A(b) gene resistant to corn earworm (Helicoverpa to recognize distinguished scholars and to bring their point of view zea), European corn borer (Ostrinia nubilalis), and fall armyworm (Spodoptera frugiperda) was compared with two non-transgenic to ASHS members; and to encourage the development of a holistic varieties, ‘Prime Plus· (a variety 80% similar to ‘GSS 0966·) and philosophy within the horticultural science profession so that ASHS ‘Silver Queen·, with full, supplemental, and no irrigation. The seed members and students can enjoy the benefits of a broader perspective of transgenic variety ‘GSS 0966· and ‘Prime Plus· were provided by provided by an understanding of the interrelationship of seemingly Syngenta. The varieties were planted in randomized complete block diverse disciplines.” design with four to six replications. Corn cobs were harvested from 2 plants over 13.5 m area from each plot to determine fresh corn yield Jules Janick is the James Troop Distin- and yield components. Plants from two middle rows were scored for guished Professor of Horticulture at Purdue foliage damage while 12 randomly selected cobs were scored for insect University. A member of ASHS since 1952, damage. With full irrigation,‘GSS 0966· and ‘Prime Plus· had 15.2 Janick served as president in 1987, editor of and 14.3 rows of kernels per cob, respectively, compared to 12.7 rows HortScience from 1970 to 1983, editor of for ‘Silver Queen·. The fresh corn yield was 15.4 and 15.2 Mg/ha for the Journal from 1976 to 1983, and editor- ‘GSS 0966· and ‘Prime Plus·, respectively compared to 13.2 Mg/ha in-chief of ASHS Press from 1998 to 2003. for ‘Silver Queen·. Only 5.6% of the total number of cobs of ‘GSS He has been awarded honorary doctorates 0966· were damaged (lacerated) by insects compared to about 92% from the University of Bologna (1990) and of the cobs of non-transgenic varieties. With supplemental irrigation, the Technical University of Lisbon (1994) the corn yield ranged from 4.5 Mg/ha for ‘Prime Plus· to 7.9 Mg/ha and has written or edited over 100 volumes. for ‘GSS 0966· but the differences were not statistically significant, Janick·s research interests have been in fruit though transgenic corn cobs had significantly more rows of kernels breeding and tissue culture, but his passion than other varieties. The ‘GSS 0966·cobs sustained about 21% damage is in the history of horticultural science and due to corn weevil (Sitophilus granarius) compared to 98 to 100% technology as reflected in the artistic record. damage due to corn earworm and European corn borer on the cobs Jules Janick of ‘Prime Plus· and ‘Silver Queen·. Under rainfed conditions,‘GSS 0966·produced more number of rows of kernels per cob and had 35% AWARDS CEREMONY (Immediately follows Lecture) higher fresh corn yield compared to non-transgenic varieties. Again, in ‘GSS 0966·, only 12.5% of total number of cobs had lacerations Presentation of the 2003 Class of ASHS Fellows due to corn earworm, whereas about 87.5% and 83.3% cobs of ‘Prime Presiding: L. George Wilson, ASHS President Plus· and ‘Silver Queen·, respectively were damaged by this insect. There was no foliage damage on any of the varieties, although some Presentation of the 2003 ASHS Awards bud worm damage was observed early in the season at all experimental Presiding: Fredrick A. Bliss sites. Thus, the yield advantage from growing transgenic Bt sweet Outstanding Undergraduate Educator Award corn may be reduced under less favorable growing conditions, but the Outstanding Graduate Educator Award production of corn, free of insect damage, with or without irrigation, Outstanding Extension Educator Award could result in greater profits to the farmer. Outstanding Researcher Award Outstanding Industry Scientist Award 9:00 am–10:00 am BUSINESS MEETING 554B Outstanding International Horticulturist Award President's Corporate Council Cross-Commodity Publication Award Chair: Larry Knerr Vegetable Publication Award Education Publication Award 9:00 am–10:00 am COMMITTEE MEETING 554A Fruit Publication Award Collegiate Activities Committee Ornamentals Publication Award Chair: George Fitzpatrick Vegetable Publication Award (Biographies of awardees begin on p. 869)

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12:00 noon–1:00 pm RECEPTION Westin-Blackstone Room years some growers had been testing green snap beans as a new crop Awardee Reception [by invitation only] for the area. The objective of this experiment was to evaluate 10 green snap beans with round pod. The date of sowing was on March 27 2000. The first harvest was 63 days after the sowing and it was for 20 days 12:00 noon–1:30 pm LUNCHEON Westin-Washington Room with four cuttings. The varieties with more yield were: Shade, Savan- Past-Presidents and Emeriti Luncheon nah, Leader and Benchmark with 365, 351, 314 and 298 boxes/ha (30 pounds/box) respectively. The HMX8996, Probe and Derby varieties 12:30 pm–1:30 pm POSTER SESSION 1 Ballroom A yielded between 29 and 74 boxes/ha. The pod quality distribution was (Location numbers for the posters within the 16%, 30%, 40% and 14% for classification 1, 2, 3 and no commercial Poster Viewing Area are in parenthesis) value respectively. The Savannah variety was with the best pod color (dark green) but with the smallest size. We did not have any important Genetics & Germplasm pests and diseases during the time of the experiment. (206) Differential Infestation of Currant Borer in Ribes (208) Collection and Conservation of Ullucus tuberosus in Cultivars Colombia, South America Kim Hummer*1, Andrey Sabitov2 Mauricio Parra-Quijano1, Carlos Nustez2, Luz M. Reyes*3 1NCGR-Corvallis, USDA ARS, 33447 Peoria Road, Corvallis, Or- 1 egon, 97333-2521, 2Far East Experiment Station, N. I. Vavilov All ETSI Agronomos, Universidad Politecnica de madrid, Ciudad uni- 2 Union Research Institute of Plant Industry, Vavilova Str. 4, Apt. 51, versitaria, 28040, Madrid, 28040, Spain, Agronomia, Universidad 3 Vladivostok, Primorye, 690025, Russian Federation Nacional de Colombia, Ciudad Universitaria, Bogota, Colombia, Hort. Sci., NCSU, Kilgore Hall, P.O. VBox 7609, Raleigh, NC, 27695 The currant borer (Synanthedon tipuliformis Clerck), a clearwing moth, is a pest of black, red, and white currants (Ribes L.) throughout The edible tuber known as ulluco (Ullucus tuberosus Caldas) is the world. While broad spectrum insecticides are the standard control, important for the diet of Colombian Andean communities, especially more environmentally friendly techniques, such as mating disruption those living at or above 2700 meters above sea level. Although it is a using synthetic pheromones, are also successful. Genetic resistance is crop with extensive perspectives toward the future, the impact of the not extensively reported or employed as a pest control strategy. We modern agriculture has displaced the cultivation of the ulluco, causing screened 150 diverse black (Ribes subgenus: Ribes section: Botrycar- serious risks of genetic erosion for this species. In order to collect its pum), red and white currants (Ribes subgenus: Ribes section: Ribes) genetic variability and establish a national genebank, three expeditions at the U. S. Department of Agriculture, Agricultural Research Service, were carried out between 1998 and 2000. The regions of Boyacá, Cauca, National Clonal Germplasm Repository-Corvallis, for natural infesta- Cundinamarca and Nariño were prospected. These regions were previ- tion by currant borer. Fifty dormant canes (about 20 cm) of 1-yr and ously reported with high variability and consumption. The recollection 2-yr wood, and about 15 of 3-yr or greater wood, were collected from took place in small farms and in local markets. In most cases the type of each cultivar. Canes were cut transversely every 0.5 cm, and dissected material collected was a mixture of clones (genotypes) called “varieties” longitudinally when needed. The average number of larvae per cane was by the local farmers. The collections were classified by tuber form and calculated. Most larvae were found in 2-yr or older shoots. In highly color and each selection constituted a ‘morphotype·. A total of 40 dif- ferent morphotypes were identified. Each selection was registered and infested black currant cultivars, such as R. nigrum L. ‘Ojebyn·, ‘Lissil·, entered the genebank as a new accession. The phenotypic description and ‘Tough Champion·, 2 or 3 larvae were observed within one cane. Judging from the cultivar pedigrees, we suspect that a European red of some accessions found in the Colombian northeastern Andean area, currant species, R. multifl orum Kit. ex Schult., contributes cane borer corresponds faithfully to an intermediate form among the wild ulluco (U. aborigineus) and the cultivated form (U. tuberosus), described by resistance. ‘Detvan·, ‘Mulka·, ‘Redstart·, ‘Rolan·, ‘Rosetta·, ‘Ron- some authors as “semi-cultivated” form or “relics of old cultivars”. This dom·, and ‘Rovada·, had low larval counts, although a few hybrid R. form can give very valuable information for the study of the evolution multiflorum cultivars, such as ‘Blanka·, were highly infested. The R. of this crop, whose center of origin has being reported among Bolivian nigrum‘Black Naples·derivatives, ‘Saunders·and ‘Kerry·, had low borer Andes and the north area of Argentina. The first Colombian genebank counts, although ‘Neosypayushayasya·was highly infested. Some black currant cultivars from Northern Sweden, Czech Republic, and England for this species was established at the field and a duplicate was placed had low counts. Infestation levels of cultivar checks from different rows under in vitro conditions, at National University of Colombia. The within the field were similar. Additional study will examine cane borer database (BD BAGUC) was designed for its management. counts of wild Ribes species. Genetic resistance, or non-preference, of cane borer, could provide an additional tool for an integrated cane (209) Updated Gene List for Watermelon (Citrullus borer management control strategy for currant growers. Breeders could lanatus) incorporate cane borer resistance into breeding schemes. Nihat Guner, Todd Wehner* Department of Horticultural Science, North Carolina State Univ., 222 (207) Evaluation of 10 Green Snap Beans in the Northwest Kilgore Hall, Raleigh, NC, 27695-7609 Mexico Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is a J.A.C. Navarro-Ainza*1, Raúl Leonel Grijalva-Contreras1, 3, major vegetable crop in the world, accounting for 2% of the world area Arturo Lopez-Carvajal2 Gerardo Araiza-Celaya3, devoted to vegetable crops. Watermelon is a useful vegetable crop for Eduardo Liñeiro-Celaya3, Francisco López-Vilchez3, genetic research because of its small genome size, and the many avail- Victor Salvador-Rivas3 able gene mutants. A list of watermelon genes was originally organized and summarized by Poole (1944). Robinson et al. (1976) expanded the 1Campo Experimental Caborca, INIFAP, Apartado Postal 125, gene list further. The list has been coordinated by the Cucurbit Genetics Caborca, Sonora, 83600, Mexico, 2Campo Experimental Caborca, Cooperative since 1979, and has been updated approximately every INIFAP, Apartado Postal 125, Caborca, 83600, Mexico, 3Growers four years, most recently in 1999. There is some confusion about the of the SOCOADA and FIRA Club. Apdo. Postal No. 125 Caborca, action of some genes or their interaction with other genes that control Sonora. Mexico. 83600 similar traits. The objective of this work was to update the gene list, The agricultural activity in Caborca, Mexico depends on fruit identify the cultivar or line having each gene mutant, and collect seeds and vegetable production, and the main crops are grapes, olives and of the lines for use by interested researchers. Finally, we expanded and asparagus. The total with this is about 27000 ha. However, in the last clarified the gene descriptions, added information on gene interactions,

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and corrected errors in naming or citing previously described genes. (212) Segregation of Red Leaf Characters in Grapevine FRIDAY pm We listed the genes as seed and seedling mutants, vine mutants, flower Rootstock Hybrid Populations mutants, fruit mutants, resistance mutants, protein (isozyme) mutants, Peter Cousins*, Laurie Boyden DNA (RFLP and RAPD) markers, cloned genes, and gene linkages. Seven genes that have not previously been described (cr, cgr, dw-3, Plant Genetic Resources Unit, USDA-ARS, New York State Agricultural ms2, Ti, ts and zym) were added to new list, for a total of 164 water- Experiment Station, Cornell University, Geneva, New York, 14456 melon gene mutants. Grapevine (Vitis spp.) rootstocks can be very similar in appearance to the fruiting varieties grafted on them. Obvious morphological mark- ers that can be used to distinguish rootstock shoots from those of the (210) Four Cultivars of Iochroma (Solanaceae) scion would facilitate grapevine grafting and vineyard establishment Alan Meerow*1, Rick Schoellhorn2 and management. A similar strategy is used in peach orchards, where 1National Germplasm Repository, Subtropical Horticulture Research a red leaf character is used to identify rootstocks. We are incorporating Unit, USDA-ARS, 13601 Old Cutler Rd., Miami, FL, 33158, 2En- obvious morphological markers into grapevine rootstock populations. vironmental Horticulture, University of Florida, 1545 Fifield Hall, Grapevines expressing the red leaf factor have bright red leaves in the Gainesville, FL, 32611 fall, and young seedlings have reddish shoot tips, stems, and buds. Iochroma cyaneumis a soft-stemmed shrubby Ecuadorean endemic The red leaf factor is considered to be due to a dominant single al- species of Solanaceae generally found between 1800 and 2500 m eleva- lele, although its relationship to other anthocyanin regulatory genes in tion. The species is usually described as having dark blue flowers. We grapevine has not been described. We studied the segregation of red announce the formal recognition and release of three distinct color forms leaf characteristics in four populations, derived from crosses of four of this species, ‘Indigo·, ‘Royal Blue·, ‘‘Sky King·, and a forth cultivar, grapevine rootstock varieties, none carrying the red leaf factor. The fi Iochroma ‘Wine Red· as yet unidentifed to species. All have shown rootstock varieties were the interspeci c hybrids Harmony, Freedom, remarkable heat tolerance in south Florida, given their elevation range 5A, and 5BB. The sources of the red leaf factor were Alicante Bouschet, in habitat. We believe that these ever-blooming, fast-growing, and easy a V. vinifera cultivar (parent of three populations) and HN12, a com- to propagate cultivars have great potential for use as landscape shrubs in plex interspecific hybrid cultivar (parent of one population). Seedlings USDA Hardiness Zones 9B-11, root-hardy perennials in Zones 8B-9A, were grown in a greenhouse and scored for color at about one month and as annuals and/or flowering pot plants in all zones. We also present of age. Two hundred eight seedlings were scored overall. In all four AFLP analysis of the four cultivars. ‘Wine Red· is the most genetically populations, segregation of seedlings for presence or absence of red distinct of the four. Material of these cultivars is available for research leaf characteristics was consistent with a 1:1 ratio. We conclude that purposes through the National Plant Germplasm System. both Alicante Bouschet and HN12 are heterozygous for the red leaf factor. The red leaf factor can be introduced into grapevine rootstock genetic backgrounds and its expression and segregation in those ge- (211) Population of Origin Affects Leaf Structure and netic backgrounds is consistent with its behavior in grapevine scion Nutrient Concentration of Pecan Seedlings cultivar populations. L.J. Grauke*1, Bruce W. Wood2, Tommy E. Thompson1, 3 J. Benton Storey (213) NY1829: A New June Bearing Strawberry from 1Pecan Breeding, USDA ARS, 10200 FM 50, Somerville, TX, 77879, Cornell University for Mid Season Production 2 SE Fruit & Tree Nut Lab, USDA ARS, 21 Dunbar Rd., Byron, GA, Courtney Weber*, Kevin Maloney, John Sanford 31008, 3Horticultural Science, Texas A&M University, Horticulture, Forestry Bldg., Mailstop 2133, College Station, Texas, 77843-2133 Horticultural Sciences, Cornell University, 630 W. North St.-NYSAES, Geneva, NY, 14456 Seed was collected from 4-5 trees growing in each of 19 native pecan populations distributed from Illinois to Oaxaca, Mexico. Seedlings were A new mid season strawberry, NY1829, has been developed at planted in a replicated test (USDA ARS Pecan Provenance Orchard, Cornell University at the New York State Agricultural Experiment Sta- Byron, Georgia) having 11 blocks, with each of the 94 original seedstock tion in Geneva, N.Y. NY1829 was selected in 1996 from a population trees represented by one open-pollinated seedling in each block, and of NYUS256 בCavendish·. NY1829 has excellent fruit quality with fi 967 total trees (due to imbalance). Leaf samples were collected from berries that are bright red and rm but not hard, with excellent eating fl each tree in 1998 and 2002 for mineral analysis. In 2002, the fresh quality and avor. Fruit is long round conic with a fancy calyx, which weight, leaflet area and dry weight of leaf samples was determined. makes them very attractive. In a replicated matted row strawberry trial This permitted calculation of nutrient content on the basis of leaf area at Geneva, the harvest season of NY1829 was 2-3 days later than the fi as well as nutrient concentration by dry weight. Leaflet area varied by variety ‘Honeoye·. Yields were similar to ‘Honeoye·with signi cantly population of origin, with the largest leaflets coming from seedlings larger fruit size over the harvest season. NY1829 average fruit size was originating from the northern and eastern range (Tennessee, Kentucky, 12.3 g compared to 10.7 g for ‘Honeoye·over the entire harvest season. Illinois, Mississippi, Missouri, Kansas, and northeastern Texas) and Firmness and bruising ratings were superior to ‘Honeoye·after 6 days at the smallest leaflets from seedlings in the western and southern range 1 °C. Insect and other disease resistance is unknown at this time but no fi (west Texas through Mexico). Leaflet density (g dry mass/cm2) also signi cant problems have been noted to date. Yield and quality compari- varied by population of origin, and was negatively related to leaflet area. sons to 8 commercial varieties will be presented. The new variety name Seedlings originating from western Texas and Mexico had the greatest and availability will be announced at the ASHS 2003 annual meeting. leaflet density. Concentration of leaf minerals varied by year, due in part to analysis by different labs. However, leaf concentrations of N, (214) Genetic Diversity of Mexican Avocados (Persea K, Ca, Mg, and Zn differed significantly by population of origin. The americana var. drymifolia) from Mexico Determined by highest concentrations of leaf Zn were found in seedlings originating Fluorescent-AFLP Markers from west Texas populations, and were distinguishable in Zn concen- C. Thomas Chao*1, Juan C. Reyes-Aleman2, Alejandro F. tration from seedlings originating from an east Texas population. Tree 2 1 size, measured as trunk diameter, varied significantly by population of Barrientos-Priego , Pachanoor S. Devanand origin, with the largest trees originating from populations in Mexico 1Department of Botany and Plant Sciences, University of California and Texas. This research has implications for the improved selection Riverside, Batchelor Hall, UC Riverside, Riverside, CA, 92521-0124, of regionally adapted rootstocks. 2Departamento de Fitotecnia, Universidad Autonoma Chapingo, CIC- TAMEX S.C., Chapingo, Michoacan, 56230, Mexico Forty-two Mexican avocados (Persea americana var. drymifolia)

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from the avocado gene bank at the Fundación Salvador Sánchez Colín- W.Va.), were examined in 2002. Populations from New York and Indi- CICTAMEX S.C. at Coatepec Harinas, Mexico along with seven Mexi- ana-site 1 had the greatest TCSA, while trees from West Virginia had can avocados, one West Indian avocado (P.americana var. americana), the smallest TCSA. The Maryland population bloomed earliest, while and one Guatemalan avocado (P. americana var. guatemalensis) from trees from West Virginia bloomed latest. Trees from New York had the California were examined for their genetic diversity using amplified earliest fruit ripening peak, with those from Maryland the latest. Aver- fragment length polymorphism (AFLP) markers with near Infrared age fruit weight was greater in the Maryland population, at 140 g, with fluorescence labeled primers. Six AFLP primer sets were used in the average fruit weights being similar (88 to 110 g) in the other populations. study: IRD700 E+GC/M+CAC; IRD800 E+CA/M+CAC; IRD700 Total number of fruit harvested per tree and yield efficiency varied E+GA/M+CTT; IRD800 E+CG/M+CTT; IRD700 E+GC/M+CAG; greatly among populations, with trees in the West Virginia population and IRD800 E+CA/M+CAG. A dendrogram based on the unweighted having the poorest production. Significant diversity in the parameters pair-group method, arithmetic average cluster analysis (UPGMA) was measured indicates that significant genetic resources are present in constructed based on the AFLP polymorphisms, and all the samples these populations that could be used in future breeding strategies. could be uniquely identified. This is the first time that large number of Mexican avocados from Mexico is studied using AFLP markers. The (217) NYUS304B: A New June Bearing Strawberry from implications of the findings for future avocado germplasm collection and Cornell University for Late Season Production preservation in Mexico are discussed. These results demonstrated the efficiency and ease of using AFLP markers for fingerprinting avocado Courtney Weber*, Kevin Maloney, John Sanford accessions and study avocado germplasm. Horticultural Sciences, Cornell University, 630 W. North St.-NYSAES, Geneva, NY, 14456 (215) Occurrence of Fusarium Root Rot Race 1 on Lettuce A new late season strawberry, NYUS304B, has been developed at in Yuma, Arizona Cornell University at the New York State Agricultural Experiment Station in Geneva, N.Y. NYUS304B was selected in 1989 from a population 1 2 James D. McCreight* , Michael E. Matheron , Barry R. of MDUS 4774 x MDUS 5199. NYUS304B was developed through 2 3 Tickes , Belinda Platts a joint venture with the USDA breeding program in Beltsville, MD 1U.S. Department of Agriculture, Agricultural Research Service, U.S. and its parents were screened for resistance to red stele root rot. The Agricultural Research Station, 1636 E. Alisal St., Salinas, CA, 93905, fruit of this new variety is round conical with dark red color and good 2University of Arizona, Cooperative Extension, Yuma Agricultural flavor. The flesh is firm with good texture and eating quality. In a rep- Center, 6425 W. 8th St., Yuma, AZ, 85364, 3Dole Fresh Vegetables, licated matted row strawberry trial at Geneva, the harvest season of P.O. Box 1759, Salinas, CA, 93902 NYUS304B was 2-3 days later than the variety ‘Jewel·. Yields were Fusarium root rot of lettuce, incited by Fusarium oxysporum f.sp. similar to ‘Jewel· with significantly larger fruit size over the harvest lactucae, was first observed in Japan in 1955. It affected commercial season. NYUS304B average fruit size was 12.3 g compared to 10.5 g U.S. lettuce production in 1990 in the San Joaquin Valley of California for ‘Jewel· over the entire harvest season. Firmness and bruising rat- near Huron, but did not become a serious problem in the U.S. until 2001 ings were equal to ‘Jewel· after 6 days at 1 C. Insect and other disease when it reappeared in Huron and appeared in the Yuma, Arizona lettuce resistance is unknown at this time but no significant problems have production area. It was found in the California coastal lettuce district of been noted to date. Yield and quality comparisons to 8 commercial Pajaro Valley in 2002. Occurrences of two new physiological races of cultivars will be presented. The new variety name and availability will the pathogen in Japan were reported in 2001 and 2003 based on the reac- be announced at the ASHS 2003 annual meeting. tions of three differential lettuce cultigens. Two California isolates were reported to be race 1. Results from naturally-infected field tests in Yuma, (218) Impact of Environment, Irrigation and Maturity 0n and artificially-inoculated greenhouse tests with a Yuma isolate indicate Ascorbic Acid Concentrations of Diverse Pepper (Capsicum that the population of F. o. f.sp.lactucaepresent in Yuma is race 1. ‘Costa Spp.) Germplasm Lines Grown at Two Texas Locations Rica No. 4· (resistant to race 1, and susceptible to races 2 and 3) was 1 2 3 resistant. ‘Banchu Red Fire·(susceptible to races 1 and 3, and resistant to Kevin Crosby* , Kil Sun Yoo , Daniel Leskovar , 4 race 2), which was not included in the field tests, was susceptible in the Leonard Pike greenhouse. ‘Patriot· (susceptible to races 1, 2 and 3) was susceptible. 1Horticultural Sciences, Texas A&M University, Texas Agr. Exp. Consistent with previous results from Japan, ‘Salinas 88·was resistant. Station, 2415 East Hwy 83, Weslaco, Texas, 78596, 2Vegetable and Fruit Improvement Center, Texas A&M University, 1500 Research 3 (216) Evaluation of Vegetative and Reproductive Traits in Parkway Ste. 120, College Station, Texas, 77845, Horticultural Sci- ences, Texas A&M University, Texas Agr. Exp. Station, 1619 Garner Six Populations of Pawpaw (Asimina triloba) Field Rd., Uvalde, Texas, 78801, 4Horticultural Sciences, Texas A&M 1 2 3 Sheri Crabtree* , Kirk Pomper , Robert Geneve University, Vegetable and Fruit Improvement Center, 1500 Research 1Community Research Service, Kentucky State University, Atwood Re- Parkway Ste. 120, College Station, Texas, 77845 search Facility, Frankfort, Kentucky, 40601, 2Community Research Ser- Ascorbic acid is an important phytochemical and essential vita- vice, Kentucky State University, 129 Atwood Research Facility, Frank- min, crucial to human health. However, it is extremely heat labile and fort, Kentucky, 40601, 3Department of Horticulture, University of Ken- therefore most available in fruits and vegetables, which are consumed tucky, N-318 Agricultural Sciences North, Lexington, Kentucky, 40546 fresh. Peppers have been documented as a good source of ascorbic The pawpaw [Asimina triloba (L.) Dunal] is a tree fruit native to acid, though previous investigations have focused on a limited number the eastern United States. Kentucky State University (KSU) is the site of cultivars. In order to assess the genetic variation for ascorbic acid of the USDA National Clonal Germplasm Repository for Asmina spp., concentration within the Capsicum genus, 82 diverse lines from four therefore assessment of genetic diversity in pawpaw is an important species were planted in two diverse Texas environments. Transplants research priority. The objective of this study was to characterize vegeta- were established in a randomized complete block design with three tive and reproductive traits in six pawpaw populations originating from replications at each location. In addition, at Uvalde, plots were dupli- six different geographic regions. Trunk cross-sectional area (TCSA), cated under two separate irrigation regimes. Subsurface drip tape and flowering time, fruit ripening peak, total fruit harvested per tree, average chemical pest and weed control were utilized. Mature green/yellow fruit weight, total yield per tree, and yield efficiency were examined fruit were harvested for each plot based on commercially acceptable in seedlings that were established in 1995 in the repository orchards. size parameters. Later, fully mature red, orange and yellow fruit were Populations of 8 to 23 seedling trees, each collected from native stands harvested as well. All fruit was cleaned, deseeded, placed in sealed in six geographic regions (Ind.-site 1, Ind.-site 2, Ky., Md., N.Y., and freezer bags and stored at –80 °C on the day of harvest. Fruit samples

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of each line and plot were homogenized with metaphosphoric acid prior characteristics, and especially drought resistance of particular clone FRIDAY pm to injecting into a high performance liquid chromatography unit with an were examined. Among 13 clones under investigation at the beginning

alphaBond-NH2 column. Ascorbic acid concentrations were determined of the experiment, seven clones, which exhibited better characteristics based on comparison to the purified standard peaks. Extensive variation than standard cultivars cultivated in this area were chosen in 1996. The for ascorbic acid content among different pepper germplasm lines was results of researches done on these 7 clones in the 1996-1999 period observed. In most instances, higher ascorbic acid concentrations were are presented in this work. One of chosen clones was weak vigorous, observed for Weslaco grown peppers than for the same lines grown in while the others were medium or strong vigorous. Leaf sizes of chosen Uvalde. Irrigation effects at Uvalde were not significant in their impact clones were in the range between 8.1 cm2 and 18.3 cm2. All clones on ascorbic acid concentrations at Uvalde. However, Chile 127 and had very late blooming time, what is very important for avoiding of Bell 22 both had significantly greater levels of the nutrient with low frost damages. Fruit weight of examined clones was between 2.3 g water and Sweet Banana 181 had significantly greater levels with high and 3.8 g, and kernel percentage was between 13.6% and 47.5%. All water. At the green mature stage, green chile, yellow wax and bell clones had auto fertility percentage between 18 5 and 26%, and pol- types contained greater concentrations of ascorbic acid than jalapeno, len grain germination was between 61% and 73%. These promising Habanero and serrano types. Green chile 130 was highest at 502 ppm, clones were propagated by grafting on bitter almond rootstock and while Summer Sweet 870 Bell at 8 ppm and Jumbo jalapeno at 10 ppm planted in collection orchard, where the researches will be continued. were very low. At the red/orange/yellow mature stage, ascorbic acid was significantly higher for all lines at both locations. Among the highest (157) Changes of Soil Property, Tree Growth and Fruit were Bell 17 at 1276 ppm and Yellow Jalapeno 244 at 1143 ppm. This Quality Influenced by Greenhouse Grown Years of Asian contrasted greatly with Mild Jalapeno 207 at 436 ppm. Fully mature, colored pepper fruits are a good to excellent source of ascorbic acid. Pear (Pyrus pyrifolia) Some lines are also a good source at the green stage. Breeding for higher Wol-Soo Kim*, Nam-Gyun Kim, Soon-Ju Chung ascorbic levels at the green stage in bell peppers is underway. Department of Horticulture, Chonnam National University, 300 Yong- bong-dong, Bucku, Gwangju, 500-757, Republic of Korea (219) Lithospermum incisum for Landscape Use This study was carried out to determine the effect of greenhouse Dale Lindgren*, Daniel Schaaf cultivation on soil properties, tree growth and fruit quality in pear orchard. Chemical and physical properties of soil were analyzed. Horticulture, University of Nebraska - WCREC, 461 West University Growth characteristics in terms of the number of scale, bud size, Drive, North Platte, NE, 69101-7756 leaf size and thickness, shoot length, the number of shoot and the Lithospermums are a group of about 60 species of spring-flowering quality of fruit were investigated. EC, pH and mineral nutrient in herbs that belong to the Boraginaceae family. Few studies have been soil were increased in greenhouse cultivation. It was considered as conducted to evaluate these species for use as ornamental/landscape the inhibiting effect on the nutrient losses caused by the rain. The plant material. Seeds from several populations of Lithospermum incisum number of sprout shoot and spurs were decreased, that of water shoot were collected in central Nebraska beginning in 1987. These popula- was increased in green house cultivation. Length/diameter ratio and tions were evaluated and plants with the most productive flowering the number of scale in flower and leaf bud were higher in greenhouse traits, favorable growth traits and performance traits were selected for cultivation than those in field culture. Soluble solid content was 4 generations. A final population, designated as L. incisum ‘Pawnee· higher and organic acid content was lower in greenhouse cultured germplasm, was selected for release. ‘Pawnee· germplasm plants fruits in comparison to the fruit from conventional orchard. Above averaged 20.3 cm in height, 51.0 cm in width and 19 stems per plant. results demonstrated that greenhouse cultivation could be feasible for Several studies were conducted with this population. Plants survived the improvement of fruit quality and the promotion of fruit maturity. as long as seven years when grown in conjunction with buffalograss, But nutrient supply in greenhouse cultivation should be controlled to blue gramma grass or in vegetative-free plots in central Nebraska. avoid the excess nutrients of soil in comparison to field cultivation. There was a significant difference in seed germination of L. incisum between stratification treatments, averaging 71% germination with no stratification and 33% with 6 weeks of cold stratification. Average (158) Does Rootstock Differentially Affect Performance seed production per plant was 7533 seeds/plant. Seed weight decreased of ‘Cortland,· ‘Macoun,· McIntosh,· and ‘Pioneer Mac· throughout the season averaging .822 gm per 100 seed on July 1 to .520 Apple Trees? gms per 100 seed on Aug 19 for all plants. This species has potential use Wesley Autio*1, James Krupa2, Jon Clements3 as an ornamental landscape plant as well as for roadside plantings. L. 1Plant & Soil Sciences, University of Massachusetts, 205 Bowditch Hall, incisum flowers early in the spring (April to May), acts as a short-lived Amherst, MA, 01003-9294, 2Dept. Plant & Soil Sciences, University perennial, reseeds and is adapted to a wide geographic area. of Massachusetts, UMass Cold Spring Orchard, 391 Sabin Street, Belchertown, MA, 01007, 3Dept. Plant & Soil Sciences, University 12:30 pm–1:30 pm POSTER SESSION 2 Ballroom A of Massachusetts, UMass Cold Spring Orchard, 393 Sabin Street, (Location numbers for the posters within the Belchertown, MA, 01007 Poster Viewing Area are in parenthesis) ‘Cortland·, ‘Macoun,·McIntosh,·and ‘Pioneer Mac apple [Malus ×sylvestris (L.) Mill. var domestica (Borkh.)] trees were planted in Pomology—Culture/Production/Management all combinations on 11 rootstocks (B.146, B.469, B.491, M.9, M.9 (156) Almond Clonal Selection from the Natural NAKBT337, Mark, P.2, P.16, P.22, V.1, and V.3) in 1995. The ex- perimental design was a randomized-complete-block split plot, with 1 2 3 Frane Strikic* , Zlatko Cmelik , Mira Radunic seven replications. Cultivar formed the whole plot, which was split by 1Department of Fruit and Olive Growing, Institut for Adriatic Crops and rootstock. The interaction of cultivar and rootstock was nonsignificant Carst Reclamation Split, Put Duilova 11, 21000 Split, Croatia, 2Faculty for trunk cross-sectional area (TCA) and cumulative yield efficiency of Agriculture, Department of Pomology, Zagreb, Svetosimunska 25, (1997-2002). It was significant for cumulative yield per tree (1997-2002) 10000 Zagreb, Croatia, 3Birnja 7, 21216 Kastel stari, Croatia and average fruit weight (1997-2002); however, important variation in Almond (Amygdalus communis Spock) selection programme was the effects of rootstock from cultivar to cultivar was not seen. Over all started in 1990 when we choose 13 clones in the area of Dalmatia. The cultivars, V.1 (44 cm2) and Mark (39 cm2) resulted in the greatest TCA, researches were carried out according to validly descriptors for the and B.469 (15.4 cm2), B.491 (10.8 cm2), B.146 (8.4 cm2), P.22 (6.3 almonds. Biological, morphological, phenological and pomological cm2), and P.16 (5.2 cm2) resulted in the smallest. Greatest cumulative yields were harvested from trees on Mark (70 kg) and V.1 (62 kg), and

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the lowest were harvested from those on B.469 (30 kg), B.491 (27 kg), with heating block studies have shown that 52 °C for 5 minutes P.16 (20 kg), P.22 (18 kg), and B.146 (13 kg). P.16 (3.9 kg/cm2 TCA) or 54 °C for 2 minutes are needed to kill Mediterranean fruit flies. resulted in the most yield efficient trees, and Mark (1.9 kg/cm2 TCA) Similar temperatures would be expected to kill the Mexican fruit fly. , B.146 (1.7 kg/cm2 TCA) , and V.1 (1.5 kg/cm2 TCA) resulted in the The effects of RF heating on the post-treatment quality and ripen- least efficient. Largest fruit were harvested from trees on V.1 (184 g), ing of cherimoya, white sapote and green-skinned avocado will be M.9 NAKBT337 (179 g), M.9 (177 g), and Mark (175 g). Smallest came presented and discussed to determine whether RF may be beneficial from those on P.16 (156 g), P.22 (153 g), and B.146 (143 g). as a quarantine treatment for these crops.

(159) Effect of Soil Management Using Organic Materials (161) High Limb Pruning to Manage Densely Planted in Pear Orchard on Soil Properties, Tree Growth and Fruit ‘Tulare· Walnuts Quality Bruce Lampinen*1, Samuel Metcalf1, Wilbur Reil1, Wol-Soo Kim*, Kyu-Tek Han, Soon-Ju Chung David Ramos2 Department of Horticulture, Chonnam National University, 300 1Dept. of Pomology, University of California, One Shields Avenue, Yongbong-dong, Bucku, Gwangju, 500-757, Republic of Korea Davis, CA, 95616, 2Research Director, Walnut Marketing Board, 1540 This study was carried out to determine the effect of soil manage- River Park Drive, Sacramento, CA, 95815-4609 ment using organic materials on soil properties, tree growth and fruit Over the past ten years or so there has been a tendency for walnut quality in pear orchard cultivated for more than 5 years. Chemical orchards to be planted in high density hedgerows to provide earlier and physical properties of soil and the number of microorganisms in returns on investments. As these high density plantings mature, they soil were analyzed. Growth characteristics in terms of the number are causing increasing management problems including lower limb of scale, bud size, leaf size and thickness, shoot length, the number dieback and shifting of production higher into the canopy leading to of shoot and the quality of fruit were measured. Microorganisms and difficulty in getting adequate spray coverage. The initial objective earthworm were increased, and pH, phosphate, gas phase and organic of this study was to use hand pruning of limbs high in the canopy in matter in soil were improved in orchard cultivated using organic combination with mechanical hedging to move production lower into materials. The number of shoot and spurs were increased, and the the canopy. The study was carried out on ‘Tulare· walnuts with two height of water sprout shoot was decreased in orchards using organic rootstock (Northern California Black and Paradox) and tree spacing materials due to decreasing nitrogen content in soil. Bud size and (3.5m ×7.3m and 4.7m ×7.3m) combinations. Every other row was the number of scale were higher, leaf was smaller and thicker, and mechanically hedged during the first dormant season. After two seasons soluble solid content and firmness of fruits were higher in orchards of dormant season high limb pruning, tree height has been decreased using organic materials than in conventional cultivation. Above re- and the crop has moved lower in the canopy. There have been no sults demonstrated that cultivation using organic materials could be significant differences in yield or nut quality for the high limb pruned feasible for the improvement of soil quality, the growth of bud and trees at either rootstock or spacing. The only difference in canopy shoot, and fruit quality. light interception was a significant increase for high limb pruning treatment trees on Northern California Black rootstock compared (160) Effects of Radio Frequency Heating on Fruit Quality to the non-high limb pruning treatment trees on Northern California Black. Yield in rows hedged 2 and 3 winters previous averaged 150 of Cherimoya, White Sapote and Avocado as an Alternative and 153 percent of yields for rows hedged the previous winter. Trees Quarantine Treatment at the closer planting density tended to become water stressed more Maria Monzon*1, Bill Biasi2, Juming Tang3, Shaojin Wang3, rapidly when water was withheld to prepare for harvest than those Yoav Gazit3, Elizabeth Mitcham4 at the wider spacing. In general, increasing midday canopy light 1Pomology, University of California, Davis, 1035 Wickson Hall, interception was associated with increased yield for trees on both One Shields Avenue, Davis, CA, 95616, 2Pomology, University of rootstocks. Results suggest that high limb pruning may be a viable California, Davis, 1045 Wickson Hall, One Shields Avenue, Davis, option for managing dense, overcrowded walnut planting without CA, 95616, 3Dept. of Biological Systems Engineering, Washington significant impacts on yield or quality. State University, 213 Smith Hall, PO Box 646120, Pullman, WA, 99164-6120, 4Dept. of Pomology, University of California, Davis, (162) Performance of ‘Ginger Gold· Apple on Five 1035 Wickson Hall, One Shields Avenue, Davis, CA, 95616 Semidwarf Rootstocks fl Fruit ies may damage fruit quality and appearance and limit fruit Robert Crassweller*, Donald Smith export and import processes. These limitations require that potentially infested fruits be quarantine treated to assure Probit 9 insect mortal- Horticulture, Penn State University, 102 Tyson Building, University ity. Recently, the USDA APHIS has amended the Mexican fruit fly Park, PA, 16802 regulations and regulated interstate movement of commodities pro- ‘Ginger Gold· apple trees [Malus ×domestica (Borkh.)] on five duced in San Diego County, CA (Docket No: 02-129-1). San Diego semidwarf rootstocks were planted in 1995 at the Russell E. Larson County produces tropical and subtropical fruits, among which are Research Center at Rock Springs, PA. The planting was arranged in cherimoya, white sapote, and avocado; but these fruits are hosts of a randomized complete block design with ten individual tree repli- the Mexican fruit fly. Heat and cold treatments are the most common cations. Trees were supported with a single conduit pole attached types of quarantine treatments used on tropical fruit. Heat treatments to a wire at 300 cm above the ground and trained as a French Axe. involve exposure of fruits to forced hot air or hot water dips and At the end of the 7th growing season trees on EMLA 7, EMLA 106 although tropical and subtropical fruits can usually withstand heat and EMLA 111 were the largest and of similar size. Trees on EMLA treatments, long exposures to heat (1 or more hours) may alter fruit 9/111 and EMLA 26 were significantly smaller. Cumulative yield appearance, flesh quality, aroma or flavor. As an alternative to heated (1997-2001) was greatest on EMLA.106 and least on EMLA 111. air or water, fruit may be heated with radio frequency (RF) energy. RF Efficiency (yield/cm trunk area) tended to be highest on EMLA 9/111 treatments expose fruit to short wavelengths that activate bipolarity and least on EMLA 7. There were no consistent trends of rootstock of fruit molecules heating fruit by convection rather than conduction, influencing fruit size. Crop load varied each year but trees on EMLA.7 consequently raising fruit temperature much faster and more evenly. seemed to consistently have a lower crop load. Trees on EMLA 9/111 Temperatures of 50 to 54oC, which are needed to kill fruit fly fifth and EMLA 7 had a greater number of rootsuckers than did the other instar larvae and eggs, the most heat resistant stages, can be reached three rootstocks. in 2 to 4 minutes with RF treatments. Short temperature exposures

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(163) Research on the Training Systems for Asian Pear potential sources of variation including crop load, light intercep- FRIDAY pm (Pyrus pyrifolia cv. Niitaka) Orchards tion, seed count, and tissue mineral composition. Fruit diameter Jae-Young Lee*, Yong-Koo Kim, Hyun-Hee Han was measured weekly. Fruit weight and volume were estimated by a quadratic regression of weekly measurements. Crop load was a highly Horticulture, Kyung Hee University, Giheung-eup, Yongin-si, significant covariate for fruit size, but canopy light interception and Gyeonggi-do, 449-701, Republic of Korea seed count were not. Rootstock had no effect on fruit growth and final Tree physiology was compared according to different training size even with the removal of crop load effects. Rootstock had no methods including two conventional systems, Pergola (PG) and Y- influence on fruit quality attributes during 2001; however, in 2002, Trellis (YT) system, and a newly devised training system, Alternate Fan fruit obtained from trees on Pajam-1 tended to be less firm. Gener- (AF) system. Modified Alternate Fan (MAF) system was additionally ally, apple fruit size was influenced by crop load and other factors, compared. The AF system performed earlier canopy development with but not by rootstock. proper shoot growth, and the system had wider inter-row space. The other systems showed over-crowded canopy and narrower inter-row (166) Tree Size, Yield, and Fruit Size of ‘Summit· Sweet space. The AF system produced more fruits with higher quality than the other systems. The vigor and number of scaffold branches had to Cherry are Affected by Training System be controlled by the consideration of the vigor of main stem because Frank Kappel*1, Rob Brownlee2 there was a certain relationship between the vigor of main stem and 1Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, scaffold branches. Pruning methods could affect the growth of lateral 4200 Hwy 97, Summerland, British Columbia, V0H 1Z0, Canada, 2Pa- and current shoots, and training angle might alter the emerging of cific Agri-Food Research Centre, Agriculture and Agri-Food Canada, water sprouts. Training methods could alter the basipetal transport 4200 Hwy 97, Summerland, BC, V0H 1Z0, Canada of assimilates and the transport had negative correlation with fruit- In 1995 a trial was initiated to investigate the effect of tree train- ing as well as vegetative tree growth like shoot growth, water sprout ing system on sweet cherry (Prunus avium) growth and productivity. emergence, and leaf development. Trees of ‘Summit·were propagated on the dwarfing rootstock Tabel® Edabriz. They were trained to four training systems: angled, central (164) Rootstock Affects Performance of ‘Ginger Gold· leader, open center, and Y-trellis. The two systems, angled and Y-trellis Apple Trees were supported by post and wire whereas the central leader and open Wesley Autio*1, Robert Crassweller2, Jean-Pierre Privé3 center systems were free-standing, that is no supports were used. At the end of the trial trees trained to the open center pruning system 1 Dept. of Plant & Soil Sciences, University of Massachusetts, 205 had the largest trunk cross-sectional area (TCA) significantly differ- 2 Bowditch Hall, Amherst, MA, 01003-9294, Dept. of Horticulture, ent from the other three systems. There were no differences in TCA The Pennsylvania State University, 102 Tyson Building, University among the remaining systems. There was no difference in final tree 3 Park, PA, 16802, Atlantic Food & Horticulture Research Centre, height among the four training systems. Trees trained to the central Agrculture & Agri-Food Canda, P.O. Box 2069, Bouctouche, NB, leader system had the lowest cumulative yield (CY). There was no E4S 2J2, Canada difference in CY among the other training systems. Yield efficiency ‘Ginger Gold·apple trees [Malus ×sylvestris (L.) Mill. var domes- was not significantly different for the training systems. Fruit size tica (Borkh.)] on five rootstocks (B.9, Mark, P.2, P.16, and V.1) were varied from year to year for the first three years (1998 to 2000) that planted in 1995 at three locations (Belchertown, MA; Rock Springs, fruit size data were collected. The most consistent result was that PA; and Bouctouche, NB). The trial was arranged as a randomized the angled training system produced the smallest fruit and the open complete block with 10 replications at each site. After eight growing center trees tended to produce the largest fruit. There were no dif- seasons, trees on V.1 and Mark were similar in size and the largest. ferences in fruit size among the training system in 2001 and 2002. Smallest trees were on P.16. Trees on B.9 and P.2 were similar in When the over all average fruit size (1998 to 2002) was calculated, size and intermediate. Root suckering was greatest from P.16 and the angled planting and the Y-trellis produced the smallest fruit and Mark and least from P.2. Greatest yields (cumulatively, 1997-2002) the open center trees produced the largest. The central leader trees were harvested from trees on Mark and V.1, and lowest yields were were intermediate in fruit size. harvested from trees on P.2 and P.16. Yields from trees on B.9 were intermediate. The most yield efficient (cumulatively, 1997-2002) trees 12:30 pm–1:30 pm POSTER SESSION 3 Ballroom A were on P.16, followed by those on Mark. The least efficient trees were on V.1, and those on B.9 and P.2 were intermediate. B.9 resulted (Location numbers for the posters within the in the greatest average fruit weight (1997-2002), and P.16 resulted Poster Viewing Area are in parenthesis) in the smallest. For all performance variables, rootstock interacted Ornamental Plant Breeding significantly with location; however, those interactions contributed little to differences in performance. Additional rootstocks (includ- (171) Hybrid Verification and Fingerprinting Using Inter- ing B.146, B.469, B.491, CG.007, CG.66, G.65, M.9 NAKBT337, Simple Sequence Repeat (ISSR) Primers in Clematis M.26 EMLA, P.22, and V.3) were included at some locations and Nicole Gardner*1, Harold Pellett2, Stan C. Hokanson3 will be discussed. 1Department of Horticultural Science, University of Minnesota, 452 Alderman Hall, 1970 Folwell Avenue, St. Paul, Minnesota, 55108, 2Of- (165) Rootstock Effects on Growth and Quality of ‘Gala· fice of the Executive Director, Landscape Plant Development Center, Apple Fruit 600 Arboretum Blvd., Excelsior, Minnesota, 55317, 3Department of Yahya Al-Hinai, Teryl Roper Horticultural Science, University of Minnesota, 258 Alderman Hall, Dept. of Horticulture, University of Wisconsin-Madison, 1575 Linden 1970 Folwell Avenue, St. Paul, Minnesota, 55108 Drive, Madison, WI, 53706 The genus clematis, comprised of over a hundred different spe- A consistent effect of rootstock on apple size is not clear in the cies, is most well known for its showy vining cultivars. However, published studies. This study was conducted over three years at the shrubby clematis species are increasingly popular garden plants that Peninsular Agricultural Research Station near Sturgeon Bay, WI to have great potential for expanded use in the landscape. To investigate investigate the effects of four rootstocks (M.26 EMLA, Ottawa-3, the possibility of breeding some of these species to obtain improved cultivars, crosses were made between five shrubby clematis spe- Pajam-1, and V-605-1) on ‘Gala· apple [Malus ×domestica (Borkh) cv. Gala] fruit growth, size and quality taking into account multiple cies: C. integrifolia, C. hexapetala, C. heracleifolia, C. recta and C. fruiticosa. Progeny from these crosses had diverse phenotypic

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characteristics, although the hybrid nature of many of the progeny diversity of S. argentea. Controlled crosses between F.alatamaha and was not readily apparent. To assess the parentage of these question- S. argentearesulted in new intergeneric hybrid progeny. A morphologi- able progeny, Inter Simple Sequence Repeat (ISSR) markers with cal comparison of parents and the progeny are presented. xSchimlinia the capacity to distinguish between each of the parent species were fl oribunda Ranney and Fantz (mountain schimlinia) is proposed as developed. Three ISSR primers revealed unique banding patterns the name for these hybrids. for each of the five parent species. These markers were used to fingerprint progeny arising from self and controlled hybridizations. (174) Recovery, Propagation, and Evaluation of the Box Putative hybrids, seedlings with mixed phenotype, were found to Huckleberry, Gaylussacia brachycera possess bands unique to each parent species. Maternal-like seedlings 1 1 2 resulting from controlled hybridizations generally possessed maternal Margaret Pooler* , Ruth Dix , Rob Griesbach banding patterns, similar to seedlings resulting from self-pollinations. 1Floral and Nursery Plants Research Unit, USDA/ARS/U.S. National Two ISSR primers allowed for the unambiguous identification of Arboretum, 3501 New York Ave., NE, Washington, DC, 20002, 2Floral 22 popular vining clematis cultivars. The ISSR marker information and Nursery Plants Research Unit, USDA/ARS/U.S. National Arbore- is being used to determine genetic relatedness among cultivars and tum, 10300 Baltimore Ave., Building 010A, Beltsville, MD, 20705 species in the genus clematis. The box huckleberry (Gaylussacia brachycera (Michx.) Gray) is a slow-growing, dwarf evergreen woody groundcover that is native to (172) Screening Deciduous Azalea Cultivars for Resistance both the mountains and coastal plains of Pennsylvania, Virginia, Ken- to Azalea Lace Bug tucky, Tennessee, West Virginia, Delaware, and Maryland. It has glossy, dark green, fine-textured foliage, with new growth often red to maroon Carol Robacker*1, S.K. Braman2 colored. The box huckleberry·s global conservation status is listed as 1Horticulture, University of Georgia, 1109 Experiment St., Dept. of G3 and the state listing for Delaware, Maryland and Pennsylvania is Horticulture, Griffin, GA, 30223, 2Entomology, University of Georgia, S1 (critically imperiled). In the seven states in which it is native, there 1109 Experiment St., Department of Entomology, Griffin, GA, 30223 are less than 20 known populations of this species. Under permit, plants Azalea lace bug is the most serious pest of azalea. Cultivars with of box huckleberry have been collected from 14 native habitats in six resistance to this pest are desired by homeowners and the nursery states. Most of these plants have been established in a protected site at and landscape industries. However, little information is available the U.S. National Arboretum in Washington, D.C. We hope to use these concerning the level of resistance of commonly available cultivars. plants to achieve the following objectives: 1) In cooperation with the Previous studies have shown that plants of the deciduous species R. Maryland DNR, enhance the recovery of box huckleberry in the wild by canescens, R. periclymenoides and R. prunifolium generally have reintroducing the plant back into its native habitat in Maryland, where high levels of resistance to azalea lace bug. Cultivars of deciduous only one plant remains; 2) determine molecular genetic distances among azaleas vary from being primarily a representative of a single species collected populations to guide decisions regarding conservation, preser- to being a complex hybrid of several species. Prediction of azalea lace vation, and breeding; 3) determine optimum propagation and production bug resistance of cultivars based on species ancestry may be reliable methods so that this species may be evaluated by commercial nurseries for single-species cultivars, but probably not for complex hybrids. as a slow-growing, native, evergreen landscape plant; and 4) perform Therefore, a laboratory bioassay was conducted to evaluate lace bug controlled pollinations between accessions to create new genotypes. resistance of 26 cultivars. In the bioassay, two adult female azalea lace bugs were placed on cuttings containing two leaves, and incubated (175) Evidence of a Gametophytic Self-Incompatibility for five days. Each cultivar was replicated five times. Data collected System in Cornus florida ‘Cherokee Princess· included number of azalea lace bugs surviving, eggs laid, and frass spots. Results indicated that none of the cultivars were as resistant Sandra Reed* as the pure species R. canescens and R. periclymenoides. The most U.S. National Arboretum, USDA-ARS, 472 Cadillac Lane, resistant cultivars evaluated were ‘Heavy Bloomer· and ‘Dark Pink McMinnville, TN, 37110 Canescens·, both members of R. canescens. Other cultivars with a Low seed set following self-pollination in flowering dogwood fairly high level of resistance were ‘Prettiest·and ·Early Canescens·, (Cornus fl orida L.) has been reported by several investigators. The both members of R. canescens, and ‘Cannon·s Double· and ‘Gibral- objective of this study was to verify the presence and determine the tar·, Exbury hybrids. mode of action of a self-incompatibility system in this species. Stigmas and styles of ‘Cherokee Princess· were collected 1, 2, 4, 8, 12, 24, 48 (173) ×Schimlinia floribunda (Theaceae): A New Interge- and 72 hours after cross- and self-pollinations, stained with aniline neric Hybrid Between Franklinia alatamaha and Schima blue and observed using a fluorescence microscope. Germinating argentea pollen was present on at least 80% of the stigmas that were collected 4 or more hours after either cross- or self-pollination. Differences 1 1 2 Thomas Ranney* , Thomas Eaker , Paul Fantz , in pollen tube lengths between ‘Cherokee Princess· cross- and self- 3 Clifford Parks pollinations were observed in samples collected from 4 to 72 hours 1Horticultural Science, North Carolina State University, 455 Research after pollination. From 4 to 24 hours after pollination, pollen tubes Dr., Fletcher, NC, 28732, 2Horticultural Science, North Carolina State of cross-pollinated specimens were approximately twice the length University, Box 7609, Raleigh, NC, 27695, 3Biology, The University of of those from self-pollinations. By 48 hours after pollination, cross- North Carolina at Chapel Hill, 414 Coker Hall, Chapel Hill, NC, 27599 pollen tubes were observed emerging from the base of the style while Franklinia alatamaha Bartr. ex Marshall represents a monotypic self-pollen tubes had only penetrated the top one-third of the style. genus that was originally discovered in Georgia, but is now considered This study provides evidence of a gametophytic self-incompatibity extinct in the wild and is maintained only in cultivation. Although system in C. fl orida. Frankliniais very ornamental, with showy flowers and crimson/maroon fall foliage color, it tends to be short lived in the landscape and is known (176) Genetic Analysis of Postharvest Longevity and to be susceptible to a variety of root pathogens. Schima argentea Pritz Quality Traits of Antirrhinum majus L. is an evergreen tree that is native to Western Asia and is valued for its glossy foliage, late-summer flowers, and broad adaptability in mild Jaime A. Pass*, Dennis P. Stimart climates. Hybridization between Franklinia and Schima could poten- Department of Horticulture, University of Wisconsin-Madison, 1575 tially combine the cold hardiness and desirable ornamental character- Linden Dr., Madison, WI, 53706 istics of F.alatamaha with the greater adaptability, utility, and genetic Many current cut flower preservatives are known carcinogens or

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environmentally toxic, thus breeding for increased postharvest longev- age. It produces bright golden-yellow autumn color. B. platyphylla FRIDAY pm ity (PHL) has become an important consideration for breeders. The Sukatchev. ‘VerDale·(Prairie VisionTM Asian White Birch) is a stress objective of this study was to evaluate genetic variance components, tolerant selection of Asian white birch native to western China. The heritability, and phenotypic correlations between PHL and quality bark is chalky white with blackish markings. It produces an upright,

traits of cut flower Antirrhinum majus L. Of 105 F5 inbred lines pre- oblong to semi-pyramidal form. The broad triangular-deltoid leaves viously evaluated for PHL and quality traits, 38 were selected from color golden-yellow in the fall. Both cultivars have resisted heavy within three PHL categories (long, middle, and short) for the current borer pressure for 30 years, are winter-hardy in USDA Hardiness

study. The selected F5 inbreds were intermated in a half-diallel mating Zone 3 and may be grown either single or multi-trunked.

scheme to create F1 hybrids. A representative sample of 76 F1 hybrids was chosen among and within categories for greenhouse evaluation (179) Identification of Tsuga Germplasm by Morphology in Fall 2002. F plants were grown in a randomized complete block 1 and Rapd Analysis design consisting of eight blocks and three replications within each 1 2 3 block. Plants were harvested and evaluated for postharvest longevity Mark S. Roh* , Nam Sook Lee , Laua De Benedetti , and quality traits including height, stem diameter and strength, days Kang Zhou4 to flower, floral head density and uniformity, individual floret size, 1Floral and Nursery Plants Research Unit, USDA, ARS, National branching habit, cut flower weight, and senescence symptoms (wilt- Arboretum, B-010A, Rm 238, 10300 Baltimore Ave., Beltsville, MD, ing, drying, or browning of florets, wilting of leaves and bentneck 20705, 2Department of Life Sciences, Ewha Womans University, Seoul, of stem). Genetic variance components, heritability, and phenotypic 120-750, Republic of Korea, 3Instituto Sperimentale per la Floricol- correlations between traits will be presented. tura, Sanrema, Imperia, Italy, 4Nanjing Botanical Garden, Institute of Botany, Jiangsu Province, People's Republic of China (177) Considerations for Quality Trait Selection in Germplasm collection is important to maximize the genetic diver- Antirrhinum majus L. (Snapdragon) sity and germplasm conservation. Tsuga chinensis (Franch.) Pritzel, T. dumosa (D. Don) Eichler, and T. chinensis var. forrestii Downie William Martin1, Jaime A. Pass*, Dennis Stimart2 germplasm was collected from three localities, Mt. Yulong, Wenfeng 1 Horticulture, University of Wisconsin - Madison, 1545 Linden Drive, temple, and Mt. Dishiergu, Yunnan Province in the People·s Republic 2 305 Plant Sciences, Madison, WI, 53706, Horticulture, University of China. Identification of the accessions was based on morphologi- of Wisconsin - Madison, 1545 Linden Drive, 341 Plant Sciences, cal characters and molecular markers. The morphological characters Madison, WI, 53706 examined included the shapes of the apex and margin of needles, and Narrow sense heritabilities and genetic correlations of ornamental the length and width of needles, cones, and seeds. Molecular markers quality traits of Antirrhinum majus L. were evaluated with special generated by randomly amplified polymorphic DNA (RAPD) were reference to cutflower postharvest longevity (PHL). Inbreds P1 (16 also analyzed to interpret species taxonomy. Although the clustering

day PHL) and P2 (3 day PHL) were hybridized to produce an F1 (P1 by genetic markers was not consistent with morphological charac-

×P2) that was self-pollinated to produce an F2 population. The F2 were ters of the needles, based on the overall morphological characters of

self-pollinated to produce F3 families that were advanced through single- cones, and seeds, and on RAPD markers, accessions from Mt Yulong

seed descent by self-pollination to the F5 generation. P1, P2, F1, F3, and Wenfeng temple were identified as T. chinensis var. forrestii,

F4, and F5 were evaluated for ornamental quality traits. Narrow sense and accessions from Mt. Dishiergu were identified as T. dumosa. heritability (h2) estimates were high and consistent across generations Taxonomic identification of accessions based on morphology and examined. Phenotypic and genotypic correlations revealed underly- by RAPD markers concurred. However our results indicate that the ing physiological and pleiotropic interactions relevant to breeding shape of the apex and margins of needles, which previously were one programs aimed at simultaneous improvement of ornamental quality of several taxonomic characters to identify mature plants, could not traits. Relevant genotypic correlations of PHL with other quality traits be used solely to separate T. dumosa and T. chinensis var. forrestii, ranged from ± 0.35 - 0.77 ± 0.10. Index selection, based on cumulative particularly seedling populations, from Yunnan Province, China.

information from the F3, F4 and F5 generations, would be more effec-

tive than F5 family selection. Theoretically, selection for quality traits 12:30 pm–1:30 pm POSTER SESSION 4 Ballroom A can proceed rapidly. (Location numbers for the posters within the Poster Viewing Area are in parenthesis) (178) Introduction of Two New Birch Cultivars with Re- sistance to Bronze Birch Borer Nursery Crops—Water, Nutrient, and Soil Management Dale E. Herman*1, Larry J. Chaput2, Wenhao Dai3 (58) Organic Mulches as Herbicide Carriers for 1Department of Plant Sciences, North Dakota State University, Lofts- Container-grown Woody Ornamentals 2 gard Hall 266E, Fargo, ND, 58105, Department of Plant Sciences, Gary Kling*1, Jayesh Samtani1 North Dakota State University, Loftsgard Hall 270G, Fargo, ND, 1 58105, 3Department of Plant Sciences, North Dakota State University, Natural Resources and Environmental Sciences, University of Illinois, Loftsgard Hall 266C, Fargo, ND, 58105 1201 S. Dorner Drive, Urbana, IL, 61801 Among popular tree genera available in the commercial nursery An integrated approach to weed control in nursery containers is trade, Betula (birch) continues to be a highly desirable component of pivotal if herbicide applications over the growing season are to be re- duced. This experiment, conducted at Urbana, Illinois and at Columbus, the landscaper·s palette. The papery white bark produced by Betula papyrifera Marsh. and other white-barked birch species add a distinc- Ohio evaluates rice hulls, pine bark and landscape leaf waste pellets as fl tive dimension to landscapes year round, particularly in the winter slow release herbicide carriers for the pre-emergent herbicides—Sur an fi scene. The greatest threat to longevity of these birches has been at- A.S. and Karmex 80DF. The ef cacy of the treatments in controlling tack by the bronze birch borer (Agrilus anxius Gory). Two new birch annual weeds, and the phytotoxic effects of the treatments on the land- cultivars displaying excellent resistance to the borer have recently scape plant species were evaluated in separate completely randomized fi been named and introduced at North Dakota State University. B. designs. For the ef cacy experiment, no landscape plants were present and pots were each seeded with a 1:1:1 volume mixture of Poa annua, papyrifera ‘Varen· (Prairie DreamTM Paper Birch) was selected from Senecio vulgaris a native Killdeer Mountain seed source in western North Dakota. and Capsella bursa-pastoris applied at a volume of This stress tolerant birch produces snow-white, exfoliating bark. Its 0.63 ml. For the phytotoxicity part of the experiment, three woody Spiraea ×japonica fl Thuja occidentalis growth habit is semi-pyramidal to upright, becoming broadly oval with plant species— ‘Gold ame·,

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‘Nana· and Spiraea nipponica ‘Snowmound· were used. Treatments 8 weeks with a complete liquid fertilizer (21N–2.2P–16.4K; 100 mg·l –1 included direct spray application of the herbicides, a combination of an N; pH 6.0) consistently exhibited BAGS. Growing the seedlings inside herbicide adhered to mulch, or either of the mulches alone. Evalutions a structure covered with insect-excluding fabric (0.1 mm2mesh opening) were done 45 and 120 days after treatment (DAT). At 45 DAT, Rice did not reduce the incidence of BAGS, indicating that BAGS is not a hulls + Karmex, Surflan direct, Karmex direct, Pine bark + Karmex manifestation of insect feeding damage or infection of seedlings by an and Pine bark + Surflan were the most efficacious treatments. At 120 insect-vectored pathogen. Seedlings grown in a 2:1 (v/v) mixture of DAT, Pine bark + Surflan, Rice hulls + Karmex and Karmex direct PBM and soil collected either from beneath several mature river birch gave the lowest weed populations. However, Karmex direct produced trees at the Minnesota Landscape Arboretum (RBS) or from an organic some of the least marketable landscape plants based on visual scales farm field did not develop BAGS and had significantly greater stem and shoot biomass content. In contrast, Pine bark + Surflan and Rice length, leaf area, and leaf, stem and root dry mass than seedlings grown hulls+ Karmex did not produce a phytotoxicity problem and gave in 100% PBM. Seedlings grown for 2 months in PBM and exhibiting prolonged weed control over 120 days. BAGS recovered and grew normally when cores of the medium were removed and replaced with RBS (approximately 5% of the total medium (59) Ring-porous and Diffuse-porous Xylem Structure: volume) while seedlings in PBM that received an insertion of fresh PBM remained symptomatic. RBS that was sterilized prior to blending A Component of Drought Tolerance? with PBM was still effective in preventing BAGS, indicating that the 1 2 William Bauerle* , William Inman positive influence of soil on plant growth was not dependent upon the 1Horticulture, Clemson University, 176 Poole Ag. Center, Clemson, presence of viable soil microorganisms (e.g mycorrhizal fungi). Leaf SC, 29634-0375, 2Horticulture, Clemson University, F-152 Poole Ag. nutrient analysis revealed that foliar concentrations of several macro- and Center, Clemson, SC, 29634-0375 micronutrients, including potassium, magnesium phosphorous, boron, Three tree species with differing xylem structures were used to copper and zinc were significantly higher in seedlings exhibiting BAGS fi than in seedlings with normal morphology. However, it is not yet known study the effect of water de cit on stomatal conductance (gs), net whether BAGS is a symptom or a cause of the nutritional variations photosynthesis (Anet), bulk leaf abscisic acid concentration (ABAL), fl measured. Additional investigations into potential nutritional causes leaf water potential (_L), and sap ow rates. Quercus shumardii (shu- mard oak), a ring porous species; Prunus serotina (black cherry), a of BAGS are currently underway. semi diffuse porous species; and Acer rubrum L. ‘Summer Red· (red maple), a diffuse porous species, were studied under growth chamber (61) Nitrogen Flow and Management in Container conditions. Drought stress was imposed by transplanting the trees Nurseries: An Adaptive Cycle Model into a pre-conditioned dry substrate. Net photosynthesis and gs were measured after the plants had received between five and six hours of David Sandrock*, Ray William fl Horticulture, Oregon State University, 4017 Ag and Life Sciences, light. All species showed decreased sap ow, gs, and Anet in response fi Corvallis, Oregon, 97331 to drought. All species showed signi cantly lower _L in response to drought. Bulk leaf ABA levels were not significantly different before Nitrogen (N) management in container nurseries is a complex sys-

or after drought stress development. In response to drought stress, Anet tem. Working within this system, owners, managers and employees of and sap flow rates of shumard oak declined faster than black cherry container nurseries routinely make N management decisions that have

and red maple. In response to substrate volumetric water content (Vw), consequences for the immediate nursery environment (plant growth, stomatal conductance declined at a faster rate in red maple and black yield, disease susceptibility, water quality) as well as areas beyond

cherry than shumard oak. Stomatal conductance, Anet, and _L of all nursery boundaries (surface and groundwater quality, public percep-

three species had a strong correlation with Vw. Leaf water potential of tion). Research approaches often address parts of the system (usually shumard oak decreased at a faster rate than red maple in response to parts associated with the immediate nursery environment and purpose) fi Vw, whereas Anet of red maple decreased signi cantly faster than that resulting in improved water usage, water recycling, controlled release

of shumard oak in response to Vw. The results indicate differences in fertilizers, catch strips and other best management practices that con- drought response among species of known xylem structure variation. tribute to improved N use efficiency. Research approaches that consider Further research is warranted to elucidate potential drought tolerance the whole system reveal novel relationships and patterns that identify mechanisms that may be exploited. areas for future research efforts and may serve to direct future manage- ment decisions. To investigate N management from a whole system (60) Abnormal Growth of Containerized River Birch perspective, a group of container nursery managers from Oregon and scientists from Oregon State University was developed. The group met ( Betula nigraL.) Seedlings Growing in Peat-based Medium three times between 2001 and 2003. Growers drew their N management 1 2 3 Steve McNamara , Harold Pellett , Carl Rosen , systems and identified components, relationships and feedback loops. Stan C. Hokanson*4 From this information, participants developed a model based on the 1Department of Horticultural Science, University of Minnesota, 3675 Adaptive Cycle that represents N flow and management in container Arboretum Boulevard, Chanhassen, MN, 55317, 2Office of the Execu- production systems. Several items of management/research interest tive Director, Landscape Plant Development Center, 600 Arboretum emerged from the model including the relative importance of reducing N Boulevard, Excelsior, MN, 55331, 3Department of Horticultural inputs in order to truly reduce N leaching from container nurseries, the Science, University of Minnesota, 305 Alderman Hall, 1970 Folwell role that scale plays in defining N imbalances in the environment and Avenue, St. Paul, MN, 55108, 4Department of Horticultural Science, the determination of N “leaks” in the system. The model is a learning University of Minnesota, 258 Alderson Hall, 1970 Folwell Avenue, tool around which nursery managers, policy makers and researchers St. Paul, MN, 55108 can center discussions for future directions. River birch seedlings grown in peat-based, soilless media (PBM) frequently exhibit stunting, short internodes and small, distorted leaves (62) Slope and Underlay Affect Runoff Percentage for with necrotic margins. This abnormal morphology, which we refer to as Woven Polypropylene Ground Cover BAGS (birch abnormal growth syndrome), results in a high percentage J.B. Million*1, T.H. Yeager1, H.B. Bryant1, C.A. Larsen1, of seedlings unusable for commercial production or research applica- 1 2 tions. Several experiments were conducted to quantify the impact of J.K. Shook , J.P. Albano BAGS on growth of greenhouse-grown river birch seedlings and to 1Department of Environmental Horticulture, IFAS, University of Flor- help elucidate the underlying cause of this phenomenon. River birch ida, PO Box 110670, Gainesville, Florida, 32611, 2U.S. Horticultural seedlings grown in the greenhouse in a PBM and irrigated weekly for Research Laboratory, United States Department of Agriculture, 2001

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South Rock Rd, Ft. Pierce, Florida, 34945 can occur. The objective of this study was to determine how pre-plant FRIDAY pm Woven polypropylene is used extensively in container plant nurseries moisture loss affects subsequent growth and flowering performance as a durable surface for container production. To better understand the of containerized plants. Twenty four hours prior to the start of the fate of irrigation water, we designed and constructed platforms (2.9 experiment, plants were dug bare-root and immediately placed into m2) to measure the relative amounts of runoff and leachate from single wet storage where freestanding moisture was maintained on the plants irrigation events as affected by slope and underlay beneath polypro- using periodic overhead mist. To allow for different levels of moisture pylene. Polypropylene covered platforms at slopes of 1.5% and 11% loss, plants were then allowed to air dry for 0, 1, 3, 5, or 7 hours. Five or were tested with each of five underlay treatments: none, coarse sand, seven hours of drying resulted in 40% to 80% dead plants and increased coarse sand with 50% of surface area removed, gravel, and native sand time to flower and decreased flower shoot number for surviving plants soil. Irrigation was applied for 30 min at 1.8 cm/hour. Average runoff for the cultivars Angel Face, Blue Girl, and Peace. Moisture content percentages (runoff/runoff plus leachate) for the 1.5% slope were less averaged 43% or less for these plants compared to >50% for plants than or equal to 0.7. Runoff percentages for each underlay at the 11% not subjected to drying. No plants of First Prize died due to drying, slope were larger than for the 1.5% slope, ranging from 0.7 for coarse though the number of flowering shoots was reduced. Moisture content sand with 50% coarse sand removed to 3.1 for native sand soil. Results of these plants did not drop below 45% after 7 hours of drying. Allow- from these experiments will benefit nursery and water managers who ing moisture content to drop 43% or below appears to be detrimental must consider the impact that converting agrarian or naturally vegetated to subsequent growth and flowering or rose plants after potting. This land to container nursery production has on altering drainage water work was supported by commercial producers in Texas and Arizona. flow. Our data also provide information useful for predicting the fate of nutrients and agrochemicals deposited on ground cover or exiting (65) Use of Time Domain Reflectometry Can Reduce Water containers in nurseries. Use and Nutrient Leaching in Container Nursery Produc- tion (63) Assessing the Infectivity of Commercial Mycorrhizal Andrew G. Ristvey1, John D. Lea-Cox*2, David S. Ross3 Inoculants in Plant Nursery Conditions 1Natural Resource Sciences and Landscape Architecture, Univ. of Lea Corkidi1,2, Donald Merhaut*2, Edith Allen2, Michael Allen2, Maryland, 2102 Plant Sciences Building, College Park, MD, 20742- James Downer3, Jeff Bohm6, Michael Evans1 4452, 2Natural Resource Sciences and Landscape Architecture, Univ. 1Research, Tree of Life Nursery, 33201 Ortega Highway, P.O. Box 635, of Maryland, 2120 Plant Sciences Building, College Park, MD, 20742- San Juan Capistrano, CA, 92693, 2University of California, Riverside, 4452, 3Biological Resources Engineering, Unive. of Maryland, 1431 CA, 92521, 3Extension, Univeristy of California Cooperative Extension, Animal Science/Agr. Engr Building, College Park, MD, 20742-2315 669 County Square Dr., Suite 100, Ventura, CA, 93003 Various state and federal nutrient management regulations are The importance of arbuscular mycorrhizas for horticultural plants ensuring a re-evaluation of water and nutrient application efficiency, is well documented. Inoculation with arbuscular mycorrhizal fungi particularly when plants are grown in intensive, out-of-ground container- often improves the growth of many perennial herbaceous and woody nursery and greenhouse operations. The quantity and quality of water ornamental plants. However, horticultural crops are usually grown in used by intensive agriculture is a topic of national interest, as clean soilless potting mixes containing peat moss, perlite, vermiculite and water is a critical requirement that helps sustain natural and managed composted barks, and not much is known about the effect of these terrestrial and aquatic ecosystems. The majority of container nursery and artificial mixes on mycorrhizal colonization. We examined the infectiv- greenhouse operations in the U.S. are irrigated by overhead irrigation ity of several commercial mycorrhizal inoculants in different potting systems. Many container production systems have low irrigation water mixes. Corn plants were grown in a soil-based medium and in two interception efficiencies, since containers are large, and plants need to different soilless substrates, the commercial Sunshine # 5 mix, mainly be spaced to reduce the effects of canopy interaction. Water that either composed by Canadian sphagnum peat moss and a potting mix prepared falls between containers, or leaches from the container, may contribute with redwood bark, pine sawdust, calcined clay and sand. Mycorrhizal to nutrient runoff, particularly when soluble fertilizers are used. To and nonmycorrhizal plants were grown in “Super Cells” (3.8 cm di- increase water application efficiency, irrigation scheduling also needs ameter, 21 cm deep Ray Leach “Cone-tainers”, Stuewe & Son, Inc.). to be based on a precise technology that can integrate diurnal plant The different commercial mycorrhizal inoculants were applied at the water use, rather than using subjective ‘timed· irrigation events. Time moment of transplanting at the rate recommended by each producer. Domain Reflectometry (TDR) has been shown to precisely schedule Low rates of Osmocote 18–6–12 and Sierra Micromax were added as water applications to various soilless substrates under experimental sources of N–P–K and micronutrients, respectively. Seven replicates conditions. In 2002, this technology was integrated into a large-scale of each treatment were harvested 50 days after planting and the shoot nursery research site at the Wye Research and Education Center in Mary- height, total dry mass and percentage of mycorrhizal colonization was land. The research site consists of two 560 m2 production houses with recorded. The percentage of mycorrhizal colonization obtained with the eight replicated blocks per house. The surface of each house was lined different mycorrhizal inoculants ranged from 0% to 50%. The infectivity with two continuous layers of 6-mL polyethylene sandwiched between of each mycorrhizal inoculant varied widely among the different pot- two layers of groundcover fabric, so that all irrigation water, rainfall ting mixes. Mycorrhizal colonization was not related to plant growth. and the subsequent leachate from plant containers can be captured. Plants grown in sunshine mix were the tallest and had the greatest dry Overhead sprinklers irrigated half of the blocks; the other half were mass independently of their mycorrhizal status. irrigated by pressure-compensated drip stakes, each system delivering approximately 15 mL of water per minute into each plant container. All water applications were measured by calibrated flowmeters. Water (64) Moisture Loss from Bare-root Roses Results in Re- applications, rainfall events, N and P applications, plant N and P uptake, duced Flowering of Containerized Plants and N and orthophosphate leaching data were continuously quantified H. Brent Pemberton*1, Ursula Schuch2 from May through November in this system, with irrigation scheduling 1Horticultural Sciences, Texas A&M University, 1710 N. Highway for eight split-plots of Rhododendron cv. azalea and Ilex cornuta being 3053, Overton, TX, 75684, 2Plant Sciences, Univ. of Arizona, Forbes entirely controlled by TDR compared to the timed cyclic daily irrigation Building Room 303, Tucson, Arizona, 85721 event. Increasing irrigation interception efficiency with drip systems Each year, several million dormant rose (Rosa sp.) plants are dug reduced the total amount of nitrogen and orthophosphate leached from bare-root from production fields in Arizona and shipped to Texas where containers. The total nutrient recovery in the leachate was higher for fl they are forced in containers for the national market. During the dig- overhead irrigation for both species, re ecting the lower interception fi ging, shipping and potting operations, significant plant moisture loss ef ciency as compared to drip. Time-domain controlled plots had a

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significantly lower total water use compared to timed cyclic events for transplants. Significant interactions were detected year and cultivar, both irrigation systems and plant species. No significant differences year and planting date, and cultivar and planting date for marketable in plant dry mass between treatments were noted. Thus by increasing yield of bare root transplants. interception efficiency and reducing overall water applications, we can reduce the total amount of nutrient runoff from container-production (424) Effects of Seeding Date, Transplant Size, and Con- systems, without a loss in productivity. tainer on Growth and Yield of Pickling Cucumber David Handley*1, Mark Hutton2 (66) Constructed Wetland System for Mitigation of 1Cooperative Extension, University of Maine, Highmoor Farm, P.O. Nutrient Contaminants in Offsite Drainage from a Box 179, Monmouth, ME, 04259-0179, 2Cooperative Extension, Commercial Nursery University of Maine, P.O. Box 179, Highmoor Farm, Monmouth, Ted Whitwell*1, Milton Taylor2, Steve Klaine3 ME, 04259-0179 1Horticulture, Clemson University, 171 Poole Hall, Hort. Dept., Clem- Commercial production of most cucurbit crops is challenging in son, SC, 29634-0375, 2Environmental Toxicology, Clemson University, the northeastern United States due to short growing seasons and cool 509 Westinghouse Dr., Pendleton, SC, 29670, 3Environmental Toxicol- soil temperatures in the spring. To encourage early plant growth and ogy, Clemson Uniersity, 509 Westinghouse Dr., Pendleton, SC, 29670 harvest, plastic mulch, plant covers and transplanting may be employed. Container-grown plants from commercial nurseries require large Although transplanting cucurbit crops has been shown to improve early amounts of water and nutrients during their production cycle. Nutrients harvest, these plants are known to be susceptible to transplant shock. may be delivered through incorporation in potting media, by top-dress- Growers often use large transplant containers for cucurbits in the green- ing with granular or slow-release fertilizers, or through liquid feeding house to prevent transplant shock, but this is often not economically by injection into irrigation water. Thus, mitigation of offsite movement efficient. Determining optimum transplant size and age to encourage of nutrients in runoff is a serious concern. Wight Nurseries of Cairo, plant establishment and early harvest could improve the success and Georgia has installed 9.31 acres of planted wetlands to receive direct profitability of these crops under short season conditions. Seeds of runoff in excess of recapture needs from over 30 acres of growing cucumber (Cucumis sativa, cv. Calypso) were started in four different beds and excess water diverted from a retention basin and pond used transplant containers, including 7.6 cm diameter ×7.6 cm deep round to retain water for an adjacent watershed. Water flows though trench peat pots, 5 cm diameter ×5 cm deep round peat pots, 6 cm diameter drains between wetland cells and eventually into stilling ponds before it ×5.9 cm deep round plugs (24 count), and 3.8 cm diameter ×5.9 cm is allowed to exit the property. Water flow through the wetlands ranges deep round plugs (72 count). Seeds were started at two dates (6/11/02, from 1.6 million to 2.2 million liters per day. Monitoring data indicates 6/26/02) in each type of container to provide transplants that were 18 strong seasonal differences in nitrate and nitrite nitrogen removal ef- days and 34 days from seeding when planted. Large peat pots (7.6 ficiencies. Nitrogen removal between April and November averaged cm diameter ×7.6 cm deep) produced the largest transplants by fresh 93.3% while removal during winter months averaged 44.1%. Nitrite was weight, dry weight and number of leaves in both the 18 and 34 day never found in wetland discharge water. Nitrogen as nitrate in discharge seeding dates, followed by the 24 plug tray, the small peat pots, and the water varied from 0.05 ppm to 4.3 ppm, well below drinking water 72 plug tray. All transplants established well. There were no significant quality standards, and was below 0.6 ppm between June and Novem- differences between seeding dates on early or total yield among any ber except in September during construction activity. Orthophosphate of the container types. Transplants from the 24 cell trays produced the phosphorus removal was highly variable with highest removal occur- greatest early yield, regardless of seeding date. The 34-day transplants ring during late spring, averaging 33.6%, and some removal occurring in the large peat pots were nearly as productive, followed by the small during early fall, averaging 13.8%. However, there was a net export of peat pots, the 18-day large peat pots and the 72-plug tray plants. There phosphorus from the wetlands during winter months. Phosphorus levels were few significant differences in total yield for any of the treatments. ranged between 0.9 and 1.9 ppm. While there is currently no legal water The 24 plug trays produced the greatest yield, but all of the treatments quality standard, these levels are above the generally accepted level of produced acceptable harvests of marketable fruit. Although larger 0.01 ppm for preventing downstream eutrophication. transplant size may provide a slight increase in early yield, using high cell-count plug trays and short transplant growing periods may 12:30 pm–1:30 pm POSTER SESSION 5 Ballroom A provide a more efficient and economical method of producing cucum- ber transplants that will perform well under short growing seasons. (Location numbers for the posters within the Poster Viewing Area are in parenthesis) (425) Planting Date, Irrigation, and Cultivar Affect Yield Vegetable Crops Management—Planting Date of Lima Bean (423) Planting Date Affects Early Season Fruit Yield of Thomas Horgan*1, Kent Cushman1, David Nagel2 Strawberry (Fragraria ×ananassa Duch.) in a Winter 1North Mississippi Research & Extension Center, Mississippi State Annual Hill Production System Univ., 5421 Hwy 145 S, Verona, MS, 38879, 2Plant and Soil Sciences, Mississippi State Univ., PO Box 9555, Mississippi State, MS, 39762 John Duval*, Craig Chandler, Elizabeth Golden This study was initiated to determine conditions under which plant- Horticultural Sciences, University of Florida, 13138 Lewis Gallagher ing date, irrigation, and cultivar affect yield of lima bean (Phaseolus Rd., Dover, FL, 33527 lunatus) in northeastern Mississippi. Fresh market lima beans are popular The annual hill production system is used to produce strawberries in among consumers and producers, but the region·s climate is not ideal for west central Florida for winter markets in the eastern United States. To production due to sensitivity of flower and fruit set to high temperature supply berries between November and March, transplants are established and drought. The experiment was conducted in 2002 at Verona, Miss. fi in fruiting elds during the entire month of October. The majority of the and the design was a split plot with four replications. The main plot acreage (>95%) is planted using bare-root, non-defoliated transplants, factor was irrigation (irrigated vs. non-irrigated) and the subplot factors with the remaining acreage planted with plug plants. All transplanting were a factorial arrangement of planting date (Apr. 23, May 22, Jun. 25, is done by hand. A two-year experiment was conducted using bare-root and Jul. 22) and cultivar (‘Bridgeton·, ‘Nemagreen·, and ‘Thorogreen·). and plug plants planted on 4 dates during October. Data was separated Canopy temperatures were monitored and there were no differences in by transplant type, due to different nursery sources, and analyzed over temperature due to irrigation or cultivar. All three cultivars produced fi both years. Signi cant interactions between year and planting date, year higher pod (unshelled) and bean (shelled) yields with irrigation than and cultivar, and planting date and cultivar for marketable yield of plug without irrigation. However, there was a significant cultivar by irri-

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gation interaction. There were no differences in pod and bean yield plants/ha with means of 68.03, and 57.93 cm, respectively. In days to FRIDAY pm among cultivars with irrigation, but without irrigation ‘Nemagreen· blooming, also significant differences were obtained (P < 0.05), the and ‘Thorogreen· produced higher yields than ‘Bridgeton.·There was variety ‘Green Best·exhibited the shortest period of 47 days using the a significant planting date by irrigation interaction. Without irrigation, planting densities of 50,000, and 69,444 plants/ha. Similar response pod and bean yield for the two latter plantings (Jun. 25 and Jul. 22) was observed with the number of fruits obtaining 10, and 11 fruits were lower than any other combination of planting date and irrigation. per plant, respectively. In mean fruit weight significant differences With irrigation, pod yield was highest for the 4th planting date and bean were also obtained (P < 0.01), heavier fruits were registered with yield was highest for the 3rd and 4th planting dates. A wet spring prob- the variety ‘PX 416543· using 69,444, 50,000, and 41,600 plants/ha ably accounted for the lack of yield differences between irrigated and with 9.73, 9.86 and 9.9 g, respectively. In total yield of fresh fruits non-irrigated treatments during the two early planting dates and a dry significant differences were obtained (P < 0.01), highest yield was summer probably accounted for the significant yield differences between obtained using the ‘PX 416543· planted at 69,444 plants/ha with irrigated and non-irrigated treatments during the latter planting dates. a yield of 7517.08 Kg/ha. In overall, ‘PX 416543· exhibited best It is clear that under hot and dry conditions yield was improved by ir- agronomic performance. Highest planting density favorably affected rigation as well as by use of the cultivars ‘Nemagreen·or ‘Thorogreen·. the total yield of fresh fruits per hectare.

(426) Use of Decision Tree Analysis to Determine Optimal (428) Tomato High Density Planting for the 1st Fruit Planting Dates for Celery Cluster Harvest with Cutting Nursery Plant Darlene Desserault1, Laurie Baker1, Katrine Stewart*2 Sungkoo Yang, Soon-ju Chung, Wolsoo Kim* 1Agricultural Economics, McGill Univ., 21,111 Lakeshore Road, Ste Department of Horticulture, Chonnam National University, 300 Anne de Bellevue, Quebec, H9X 3V9, Canada, 3Plant Science, McGill Yongbong-dong, Gwangju, 500-757, Republic of Korea Univ., 21, 111 Lakeshore Road, Ste Anne de Bellevue, Quebec, H9X In order to cultivate tomato of the 1st fruit cluster harvest a lot of 3V9, Canada nursery plants were required as much as 75,000 to 100,000 plants/ha Quebec celery producers face both domestic and international in plastic house in Korea. Therefore it needs too many expenses to competition, which has resulted in the development of management buy tomato seeds, which almost were imported from abroad. This strategies to capture higher prices. One such strategy is the use of study was carried out to confirm the possibility of alternative use earlier plantings, which while potentially allowing growers to be more of the tomato cuttings instead of tomato seedlings of two varieties. competitive increase the risk of crop losses due to bolting. Celery Cutting materials of lateral shoots were taken from the harvesting plants bolt when exposed to vernalizing temperatures. Bolting risks tomato plants in commercial green house. Four to five nodes of lateral based on 10 years of weather data were calculated for 5 planting dates shoots were cut into plug tray with 50 to 128 cells, 23 to 80 mL/cell using a model developed by Alt and Wiebe (2001) for celeriac. The in cell capacity. After 5 days, rooting was initiated and it could be model assigned a 60% risk of having more than 10% bolting for the transplanted as nursery plant. The nursery plants of ‘Rockusanmaru· first, 30% for the second and 0% for the third, fourth and fifth dates. and ‘Momotarouyoku· varieties were planted to the perlite media in Thermal times were used to calculate plant growth and development hydroponics bench in green house with 111,110 plants/ha (90 cm and determine time to harvest for each planting date. Market price data ×10 cm) in planting density at May 8, 2002. The matured fruits were from 1995 – 2002 were used to calculate the average weekly prices for harvested from July 9 through July 26, 2002. The number of harvested Grade 1 celery during the harvest periods. This information was used fruits was 2.9 to 3.3 for the two varieties. The fruit weight was 138 to to develop a decision tree. The decision tree indicated that the second 153 g for ‘Rockusanmaru·, and 127 to 146 g for ‘Momotarouyoku·. planting date was optimal in terms of risk and returns. The cutting nursery plants of ‘Rockusanmaru· showed higher fruit yields as much as 51.5 tons/ha than that of seedlings as 40.3 tons/ha. (427) Evaluation of Growth and Yield of Okra There was a similar result in ‘Momotarouyoku·. The duration from cutting to harvest of 1st fruit cluster was required 89 to 105 days, as (Abelmoschus esculentus L.) Varieties Under Three well as 63 to 79 days from field planting to harvest. In conclusion Planting Densities the cultivation with tomato cutting nursery plants was considered as Francisco Radillo-Juárez1, Juan Manuel González-González2, better effects in shorter periods in nursery raising and higher yields Jaime Molina-Ochoa2, José Hyvan Castañeda-Alvarez2, in comparison to conventional cultivation with seedlings. Francisco Radillo-Juárez*3 1Facultad de Ciencias Biológicas y Agropecuarias, Universidad de 1:30 pm–2:30 pm COMMITTEE MEETING 554B Colima, Km. 40 Autopista Colima-Manzanillo, Tecomán, Colima, Horticulture Hall of Fame 2 28100, Mexico, Facultad de Ciencias Biológicas y Agropecuarias, Chair: Edward Proebsting, Jr. Universidad de Colima, Km. 40, autopista Colima-Manzanillo, Tecomán, Colima, 28100, Mexico, 3Facultad de Ciencias Biológicas 1:30 pm–2:30 pm BUSINESS MEETING 554A y Agropecuarias, Universidad de Colima, Azucena 1735, Col. Lázaro Cárdenas, Colima, Colima, 28070, Mexico International Advisory Council In Mexico, Okra is a relevant horticultural crop because about Chair: Frederick T. Davies 83% of the production is exported. Differences in yield depend upon the varieties and planting densities used. The study was carried out to 1:30 pm–2:30 pm BUSINESS MEETING 550B evaluate the growth and yield of three Okra varieties and three planting Cucurbit Genetic Cooperative densities. The evaluation was conducted in field with a loamy-sandy texture, pH 6.5, and under dropping irrigation. Three Okra varieties Chair: Timothy Ng were used: ‘Clemson Spinaless·, ‘PX 416543·, and ‘Green Best·. Three planting densities were used: 69,444, 50,000, and 41,600 plants/ha. 1:30 pm–2:45 pm ORAL SESSION 3 552B A randomized complete blocks design with bifactorial arrangement Genetics and Germplasm with nine treatments and three replications was used. Statistically significant differences were shown in the percent of emerging plants Moderator: Maria Jenderek (P < 0.05), ‘PX 416543·using a density of 41,600 plants/ha had 27% 1:30 Phenotypic Characteristics of Open Pollinated Garlic of emerged plants in four days. Taller plants were registered using Progenies the varieties ‘PX 416543 , and ‘Green Best and a density of 69,444 · · Maria Jenderek*1, Richard Hannan2 HORTSCIENCE, VOL. 38(5), AUGUST 2003 673

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1NALPGRU, USDA, ARS, 9611 S. Riverbend, Parlier, CA, 93648, transmissible, TSV has also been implicated in the virus complex. A 2WRIPS, USDA, ARS, 59 Johnson Hall, Pullman, WA, 99164 replicated field trial of 240 germplasm accession representing plant Production of true seed in garlic is well documented. However, phe- introductions and recombinant inbred lines developed from a cross notypic characteristics of plants derived from true seeds have not been of Eagle ×Pueba s was planted at Arlington, WI Research Station in reported. In this study, the progenies of 13 open-pollinated families that mid-July, 2002. Two weeks prior to planting the trial, mixed spreader originated from Allium sativum and A. longicuspis USDA germplasm rows consisting of a soybean and virus susceptible snap bean cultivar, accessions from the collection at Pullman, WA, were evaluated for an Hystyle were planted. Germplasm accessions included 170 accessions array of plant and bulb characteristics when grown in the environment from the USDA Regional Plant Introduction Station in Pullman, WA, of the Central California San Joaquin Valley. Wide inter- and intra- 10 commercial cultivars and 60 recombinant inbred lines from a cross variation was observed for the characters of plant survival (7.8% to of Eagle ×Puebla 152. Visual ratings of virus symptoms were taken. 83.3%), bulb maturity (June–December), bulb weight (0.1–53.3 g), Thirty-one accessions were phenotypically symptomless. These plots number of cloves (2.9–10.4), and the lack of ability to mature in one were resampled for AMV and CMV using ELISA, and two accessions growing season (0% to 23.5%). The extent of unfavorable attributes were virus free. These results suggest that genetic variability exists relative to production, such as low seedling survival, small bulbs, and within Phaseolus vulgaris and could serve as a source of resistance the fraction of bulbs with symptoms of physiological degradation (waxy to this soybean aphid transmitted virus complex. breakdown), varied between populations. The wide range in values for these characteristics highlights the challenges for breeders of garlic. 2:15 Inheritance and Heritability of Terbacil Herbicide Toler- However, they present the potential for sexually derived progenies that ance in Strawberry will enhance the further development of better cultivars with traits that may not be available from clonally propagated material. These char- Courtney Weber* acters would include low number of cloves, new maturity windows, Dept. of Horticultural Sciences, Cornell University, New York State or non-bolting quality in the first growing season. Agricultural Experiment Station, 630 W. North St., Geneva, NY, 14456 The herbicide terbacil (Sinbar) is one of a few herbicides approved 1:45 Characterization of Anthocyanins from Diverse Germ- for use in strawberry production. It is an effective broad-spectrum herbicide with good residual activity, low soil mobility, and low plasm of Purple Carrot mammal toxicity (caution label) and is fairly environmentally benign. Erin Silva*, Philipp Simon Unfortunately, tolerance to terbacil is highly variable among straw- Dept. of Horticulture, USDA-ARS Vegetable Crops Research Unit, Uni- berry cultivars and use of the herbicide has been associated with the versity of Wisconsin-Madison, 1575 Linden Dr., Madison, WI, 53706 incidence of black root rot in some studies possibly due to increased Anthocyanins are the brightly-colored, purple, red, and blue pig- plant stress. This wide range of tolerance to terbacil indicates a large ments found widely in higher plants and are responsible for the typical level of available genetic diversity for tolerance yet little work has colors of flowers, fruit, and leaves. Anthocyanins are glycosylated and been done to elucidate the inheritance or improve the level of toler- acylated derivatives of six cyanidins and vary widely among plants. ance to this herbicide in commercial strawberry cultivars. A complete Different additions to the base molecule result in compounds of varying diallel design was utilized with two tolerant cultivars, ‘Honeoye· and color stability and intensity. Historically, purple color was found in ‘Earliglow·, two moderately tolerant cultivars, ‘Lester· and ‘Allstar·, carrot roots and some characterization had been done to confirm that and two susceptible cultivars, ‘Red Chief· and ‘Guardian· as parents. this color was due to anthocyanins, particularly cyanidin glycosides. Seedlings from each of 36 populations were treated with 0.5 mg/plant While variation in tone and intensity of purple color has been noted in terbacil to estimate the heritability of tolerance and elucidate the in- diverse carrots, the chemical basis of this variation is unknown. Thus, the heritance of the trait. Seedlings were treated at the 5 leaf stage and identification, quantification, and characterization of these compounds tolerance was recorded at 2 weeks and 4 weeks post treatment on a in carrot roots would be useful in a breeding effort in order to select for scale of 1-10 (1 being least tolerant). Symptoms included interveinal roots with the most stable and intense purple color. We selected roots chlorosis, leaf curling, reduced vigor, and death in some cases. Heri- from different breeding lines that displayed varying shades of color tability estimates indicate significant progress in increasing the toler- in a range of intensities. Pigment was extracted using EtOH/HCl and ance of new cultivars to terbacil can be achieved through traditional analyzed using gradient RP-HPLC. Anthocyanin profiles of the lines recurrent selection procedures. were compared. As anthocyanins are widely applicable as natural food coloring agents and are potent phytonutrients with high antioxidant ca- 2:30 Studies on The Germplasm of Genus Prunus and Gennus pacity, better characterization of carrot anthocyanins will be of interest. Armeniaca Fruit Trees in Jilin Province Bingbing Zhang* fi 2:00 Identi cation of Genetic Resistance to the Soybean Aphid Jilin Academy of Agricultural Sciences, Pomology Institute, No. 6 West and Viral Disease Complex in Snap Beans Xinhua Street, Gongzhuling City, Jilin Province, P.R.China, Gongzhul- James Nienhuis*1, Michell Sass2 ing, jilin Province, 136100, People·s Republic of China 1Horticulture, Univ. of Wisconsin, 1575 Linden Drive, Madison, WI, The genus Prunus and genus Armeniaca in Jilin Province consist 53706, 2Horticulture, Univ. of Wisconsin, 1575 Linden Dr., Madison, of seven species and four varieties of which Prunus salicina and Ar- WI, 53706 meniaca vulgaris are found all over the Province. Prunus ussuriensis, The re-occurance of virus disease complex causing plant stunting, Prunus nigra and Prunus americana can only be found in those old pod necrosis and malformation as well as yield loss in snap beans orchards in Changchun city and Jilin city, Armeniaca sibirica mainly (Phaseolus vulgaris L.) was observed in the 2000-2002 growing sea- exists in western meadows and Sand banks along the Songhua river sons. The disease was widespread, and has been reported in the snap bean and the Tumen river. The chromosome number, economic character- production areas of Wisconsin, Illinois, Minnesota, Michigan, Iowa, istics, qualitative characters, hardiness of eighth Kinds of materials Kentucky, New York and Ontario, Canada. In snap beans, the disease and the current situation of their utilization are studied. We discovered is thought to be caused by a virus complex consisting predominantly a dwarf plum bud mutant with is a mixture of diploid and tetraploid of CMV (Cucumber Mosaic Virus), AMV (Alfalfa Mosaic Virus) and We also found fourteen plum and apricot varieties bear fruits of more TSV (Tobacco Streak Virus). Viruses CMV and AMV are transmit- than 40 grams per fruit, nine apricot varieties have sweet edible ted in a non-persistent and stylet-borne manner by the soybean aphid Kernels, two high-sugar plum varieties, one high-Vitamin C plum (Aphis glycines) which was first discovered in the Midwest in 2000 variety and one high-vitamin C apricot variety. Twenty-four kinds and is thought to have been introduced from Asia. Although not aphid of extremely hardy germplasm and thirty-one kinds of hardy germ-

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plasm of plum and apricot are collected. Suggestions about plum estimates and observed values of transpiration calculated from sap flow and apricot development and utilization are also being proposed. and gas exchange measurements on both a fifteen-minute and daily FRIDAY pm basis. The results indicate that when soil water is extractable, measured 1:30 pm–3:00 pm ORAL SESSION 4 556A and modeled transpiration follows that of atmospheric demand without the use of a crop coefficient. In contrast, when soil water becomes Nursery Crops—Water, Nutrient, and Soil Management limited during progressive drought, transpiration is not only reduced, Moderator: John Lea-Cox but diverges from atmospheric driving variables. The data justify the incorporation of a gas exchange function to constrain water loss when 1:30 Management of Canopy Heterogeneity in a Temperate Red transpiration is simulated under water deficit conditions. Maple Container Nursery: Simulation of Light Transfer on Radiation Absorption, Assimilation, and Transpiration 2:00 Aspects of Water and Nutrient Use Efficiency in a Container William Bauerle* Nursery System Horticulture, Clemson University, 176 Poole Ag. Center, Clemson, Andrew Ristvey1, John Lea-Cox*1, David S. Ross2 SC, 29634-0375 1Natural Resource Sciences and Landscape Architecture, University Solar radiation distribution in a canopy is three dimensional in of Maryland, College Park, Plant Sciences Bldg, Room 2120, College nature, where distribution of light over leaves is a governing factor Park, MD, 20742, 2Department of Biological Resources Engineering, in physiological and morphological processes. The application of a University of Maryland, College Park, 1431 Animal Science/Agr. Engr three-dimensional model at the intracrown and intracanopy scale was Bldg, College Park, MD, 20742 used to investigate the interaction of canopy heterogeneity and crown spacing. Variation in tree size ratio and crown spacing were simulated There are few studies in the ornamental literature that provide ac- fi on an instantaneous, daily, and seasonal basis. Net photosynthesis (A ), curate, long-term water or nutrient uptake and use-ef ciency data, and net none that provide data for large-scale nursery systems. Concerns about transpiration (E), absorbed photosynthetically active radiation (Qa), and fi nitrogen (N) and phosphorus (P) runoff, and the consequent effects on light use ef ciency (¡c) of a heterogeneous canopy were predicted to exceed that of a uniform canopy under space limiting conditions. Tree water quality, make accurate information on water and nutrient use ef- ficiency imperative for effective best management practices (BMPs). size ratio had a large effect on A , E, Q , and ¡ when light transfer to net a c A three-year study investigated aspects of water and nutrient use in lower canopy layers was limited by inadequate space between crowns. a large-scale (12,600 sq. ft = 0.33 acre) nursery research site at the Increasing daily intercepted photosynthetically active radiation (PAR) Wye Research and Education Center in Maryland. Water applications, at lower crown layers had the largest impact on whole crown and whole rainfall events, N and P applications, plant N and P uptake, and N and canopy A , E, Q , and ¡ . Although increase in canopy productivity net a c orthophosphate leaching data were continuously quantified from July led to increased water use, the simulations of heterogeneous stands 1999 to November 2002, to provide complete water, N and P budgetary under adequate soil water indicate that light absorption is maximized data, over a 40-month production cycle for Rhododendroncv. azalea and under space limiting conditions as a canopy moves toward heteroge- Ilex cornuta. The experimental system was designed to replicate a local neity. Moreover, the simulations at the intracrown and intracanopy container-production nursery system. The research site consists of two scale indicate that fluxes of carbon and water exchange increase when 560 m2 (6,300 sq. ft.) production houses with eight replicated blocks per canopy heterogeneity is maximized under space limiting conditions. house. The surface of each house was lined with two continuous layers The results indicate that nurseries can optimize productivity per unit of 6-mL polyethylene sandwiched between two layers of groundcover land area by tactical placement of several annual tree sizes, but with fabric, so that all irrigation water, rainfall and the subsequent leachate an accompanied increase in canopy water use. from plant containers could be captured. All water applications were measured by calibrated flowmeters. Nitrogen and P applications were 1:45 Red Maple Water Use Under Irrigated and Water Deficit quantified by application rate. Budgets were developed by analysis of Conditions in a Warm Humid Climate: Modeling Tran- nutrient solutions, plant and substrate material, and leachates. Half of the spiration with a 3-dimensional Mechanistic Approach blocks were irrigated by overhead sprinklers; the other half were irrigated William Bauerle* by pressure-compensated drip stakes, each delivering approximately 15 mL of water per minute into each plant container. During the first two Horticulture, Clemson University, 176 Poole Ag. Center, Clemson, years of this investigation, irrigation for both drip and overhead methods SC, 29634-0375 was cyclical. The third year compared Time Domain Reflectometry Management practices with nursery crops tend toward excessive (TDR) controlled irrigation and cyclic irrigation. Each of the replicated water use due to fears of a decline in growth and production. To date, blocks within the houses drained into a central furrow that captured fi simpli ed forms of the Penman-Monteith equation are often used to the runoff into a 200-L below-ground polyethylene drum, which was fi estimate rates of canopy transpiration from atmospheric humidity de - continuously pumped to above ground drums and metered to capture fi cits. In an attempt to establish crop coef cients, numerous models have volume data through calibrated flow meters. Sub-samples of the total been employed to estimate evapotranspiration (ET) from meteorological volume were taken for nutrient analysis immediately after fertigation, data. Lost in these common procedures are a number of plant morpho- irrigation, or rainfall events, acidified and frozen. These data allowed us logical and physiological features of both the crop canopy as a whole to develop a complete water and nutrient-use efficiency dataset for each and the individual tree within the canopy. However, three-dimensional treatment over the 3-year period, and to assess the effects of different biological process models are able to take into account canopy radiation, water and fertilization management strategies on leaching and nutrient transpiration, and photosynthesis of single trees and/or canopy layers at runoff potential, and the consequent effects on plant growth. Plant N relatively short time intervals. This type of model, which is used in this and P uptake was not significantly affected by irrigation strategy the study, holds potential advantages for nurseries, forests, and orchards first year, nor were there any differences in uptake between the species. by specifying structural parameters such as tree position, crown shape, Thereafter, Ilex cornuta took up significantly more N and P, most of fi and dimensions. In addition, speci c physiological values of the species which resided in leaves, branches and roots. Leachates accounted for under study are incorporated into our model calculations, potentially no more than 20% of the N and P budget and a large portion of the N fi yielding a more accurate estimate of water use for a speci c crop. Us- and P budget was not accounted for each year. ing the physiological and physical parameters, the transpiration values were computed and compared with the observed values. Predicted transpiration values were also compared to potential evapotranspira- 2:15 High Temperature Stress Effects on Water Use and Nutri- tion of both the Penman-Monteith with zero canopy resistance and Van ent Utilization in Container Systems Bavel combination equations. These values were compared with model Sara Johansen*1, Hannah Mathers2

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1Horticulture and Crop Science, Ohio State University, 2001 Fyffe Ct., Corvallis, OR, 97331 Columbus, OH, 43210-1096, 2Horticulture and Crop Science, Ohio Wholesale woody ornamental nurseries grow a wide variety of State University, 2001 Fyffe Ct, Columbus, OH, 43210-1096 cultivars and species with various nitrogen (N) requirements. Yet, top- Root zone temperatures are a major limitation to container pro- dress and incorporation of controlled release fertilizers (CRF) at constant duction. In above ground container systems, the roots in the western rates regardless of plant N requirements have become standard practices container quadrant are often injured or killed by high temperatures. in the nursery industry. To determine the relative efficiency of one CRF Root injury severely impacts plant water and nutrient use but the to a liquid feed program, N fertilization budgets for Euonymus alatus extent of this effect has not been well documented. We examined (Thunb.) Sieb. ‘Compactus·(a slow growing taxon) and Weigela florida the interactions of high temperature stress on the root systems of (Bunge.) A. DC. ‘Red Prince· (a fast growing taxon) were determined container grown plants and their effect on water and nutrient use. during the 2001 growing season. Based on these budgets, daily (D) Syringia meyeri albin , Hosta ide Brim , Viburnum trilobum and bi-weekly (BW) N delivery regimes (liquid feed) were developed ahs and Taxus densiformis were studied from May 1, 2002 through and tested against industry standards in a completely randomized October 1, 2002. Plants were evaluated by destructive sampling at design. Liquid feed treatments supplied 1015 and 1837.5 mg N per four dates: June 1, July 1, August 1 and September 1. Two container container over the 20 week study period for E. alatus ‘Compactus·and types, black plastic one-gallon containers, and fiber pots, mycorrhizal W. fl orida ‘Red Prince· respectively. The CRF treatments [Osmocote fungi inoculated and non-inoculated and three softwood bark/peat 18-6-12 (Scotts, Marysville, Ohio; 18N-2.6P-9.9K)] supplied between medias with varying amounts of compost, 0%, 10% and 20% were 2500 and 3500 mg N per container depending upon the rate (high or investigated. There were four single plant replications per treatment medium) and application method (top-dress or incorporation). For E. combination and harvest date. Container and ambient temperatures alatus ‘Compactus·, leaf area, total dry weight and total N of the D were recorded using thermocouples and data loggers. Shoot and root and BW treatments were not significantly different (alpha = 0.05) from length and shoot and root weight measures were collected. The main the high rate of 18 g Osmocote (3240 mg N) per container, which had effects of species, date and media type, and the interactions of harvest the highest values. However, the D and BW liquid feed treatments date by species and media type by species were significant for all introduced 68.7% less total N to the production system. Leaf area, measures. The interaction of date by media was significant for all total dry weight and total N of W. fl orida ‘Red Prince· were highest measures except root length. Root and shoot weight was highest in the when Osmocote was incorporated at the high rate of 7.12 kg·m 3 (3573 10% compost mix. The date by pot interaction was non-significant for mg N). However, leaf area, total dry weight and total N were not sig- the root weight data but was significant for shoot weight. Plastic pots nificantly less (alpha = 0.05) for the D and BW liquid feed treatments produced significantly more shoot weight than fiber in the September which introduced 48.6% less total N to the production system. After harvest; however, on the other three evaluation dates shoot weight 20 weeks the pH of the media for all treatments ranged from 6.1 to 6.6, was not significant influenced by pot type. and the electrical conductivity ranged from 0.19 to 0.84 dS/m. Results indicate that comparable woody nursery stock can be produced with significantly less N inputs than are often recommended. 2:30 Water Content of Pine-bark Growing Media in a Drying Mineral Soil 1:30 pm–3:00 pm ORAL SESSION 5 555A Anne-Marie Hanson, J. Roger Harris* Horticulture, Virginia Tech, 301 Saunders Hall, Blacksburg, VA, 24061 Vegetable Breeding Newly transplanted container-grown landscape plants are reported Moderator: Dean Kopsell to require very frequent irrigation. However, container nurseries in the 1:30 Detection of QTL for Sugar-Related Traits in Ananas and U.S. commonly use growing media that is mostly bark, even though Cantaloupe Melons the contribution of bark-based growing media to water relations of 1 1 2 2 1 transplanted root balls is unknown. Therefore, a field experiment was S.O. Park , J.W. Sinclair , K.S. Yoo , L.M. Pike , K.M. Crosby* undertaken to determine water relations of pine-bark media (container 1Texas Agricultural Research and Extension Center, Texas A&M removed) within a drying mineral soil over a three-week period. A University, Weslaco, Texas, 78596, 2Vegetable & Fruit Improvement range of common production container sizes, 3.7-L (#1), 7.5-L (#2), Center, Texas A&M University, College Station, Texas, 77845 21.9-L (#7), 50.6-L (#15), and 104.5-L (#25), was used. The fraction Sugar components such as sucrose, fructose, glucose, and total of media volume that is water (total volumetric water, TVW) within soluble solids are important factors to determine mature fruit sweetness the top and middle zones of container media was compared to TVW at in Cucumis melo L. Molecular markers linked to genes which regu- corresponding depths of adjacent mineral soil. Fraction of media and late synthesis of these compounds may improve the breeder·s ability soil volume that is plant-available water (plant-available volumetric to recover high sugar genotypes and aid in the development of high water, PAVW) was calculated by subtracting the fraction of media sugar cultivars. Our objective was to identify RAPD markers associated or soil volume below where water is unavailable to plants (measured with major QTL affecting sucrose, total sugars and brix contents using with pressure plates) (plant-unavailable volumetric water, PUVW) bulked segregant analysis in two F2 populations from crosses of Deltex from each TVW measurement. Pine-bark media had a PUVW of (high sugar ananas) ×TGR-1551 (low sugars) and Dulce (high sugar 0.32, compared to a PUVW of 0.06 for soil. Top sections of media cantaloupe) ×TGR-1551. Data for concentrations of sucrose, glucose, dried to near zero PAVW six days after irrigation for all containers. fructose and total sugars were obtained from 108 and 110 F2 plants with Larger container sizes maintained higher PAVW in middle sections their parents using HPLC. Clear separations for sucrose, total sugars than smaller container sizes, and PAVW was always higher in the and brix contents of Deltex and TGR-1551 or Dulce and TGR-1551 adjacent soil than in the embedded media. Overall, very little PAVW were observed, whereas slight differences for glucose and fructose is held by embedded pine-bark growing media, suggesting the need concentrations were found. Continuous distributions for sucrose, total for container media with greater water retention once transplanted sugars and brix contents were observed in both populations, suggesting to mineral soils. that the sugar traits were quantitatively inherited. Significant negative correlations were observed between sucrose and glucose (r = _25 and –85) or fructose (r = 0.31 and 0.58). Significant positive correlations 2:45 Fertilization Based on Specific Plant Requirements Reduces were noted between sucrose and total sugars (r = 0.79 and 0.34) or Nitrogen Inputs in the Production of Two Woody Ornamen- brix r = 0.64). Three low and high DNA bulk pairs for sucrose, total tals: Comparison with a Controlled Release Fertilizer sugars and brix were developed from F2 plants. A total of 300 primers David Sandrock*, Anita Azarenko, Tim Righetti were used to simultaneously screen between the low and high bulks, Horticulture, Oregon State University, 4017 Ag and Life Sciences, and between the parents. Several RAPD markers were found to be

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significantly associated with QTL affecting high sucrose, total sugars may affect the health benefits of consuming these leafy vegetables. FRIDAY pm and brix contents. Particularly, marker OAA19.350 was significantly associated with QTL affecting sucrose, glucose and fructose in the 2:15 Glucoraphanin Concentration of Broccoli Seed is Highly Dulce/TGR-1551 population, and accounted for 4% to 13% of the Influenced by Genotype phenotypic variation for the traits. These markers associated with the 1 2 2 sugar synthesis QTL could be useful to transfer these genes into a low Mark Farnham* , Katherine Stephenson , Jed Fahey sugar cultivar to enhance the fruit quality. 1U.S. Vegetable Laboratory, USDA-ARS, 2875 Savannah Hwy., Charleston, SC, 29414, 2Department of Pharmacology, Johns Hopkins 1:45 Evaluation of Black Rot Resistance in Cabbage Germplasm University, 725 N. Wolfe St., Baltimore, MD, 21205 Derived from Intraspecific and Interspecific Crosses The discovery that broccoli (Brassica oleracea L., Italica Group) seedling sprouts contain high levels of glucoraphanin has stimulated fi 1 2 Phillip Grif ths* , Muhammet Tonguc much interest in seed production by this crop. Glucoraphanin is the 1Horticultural Sciences, Cornell University NYSAES, 302 Hedrick precursor of sulforaphane, an isothiocyanate that may provide che- Hall, Geneva, NY, 14456, 2Horticultural Sciences, Cornell University moprotection against certain carcinogens when consumed in broccoli NYSAES, 303 Hedrick Hall, Geneva, NY, 14456 heads or sprouts. Previously, we found that selected, self-compatible Black Rot (Xanthomonas campestrispv. campestris) is a seed-trans- inbreds (conventional and doubled haploid) of broccoli will produce mitted bacterial disease of cabbage (Brassica oleracea var. capitata) significant yields of uniform seed. In the present study, we measured the that enters the plant through hydathodes at the leaf margin resulting glucoraphanin concentrations of seed produced from those same inbreds in characteristic V-shaped lesions. B. oleracea derived resistance to grown in two greenhouse and two outdoor screen cage environments. black rot is quantitative and incomplete, complicating introgression Our objective was to determine if seed glucoraphanin concentrations into commercial cabbage varieties. Alternative sources of black rot of different inbreds was consistent across environments. Seed gluco- resistance from related species including Brassica carinata (Ethiopian raphanin content was measured by a hydrophilic interaction liquid mustard) have dominant, single gene control for the two major races chromatography method employing an HPLC. In all environments, (race 1 and race 4). Populations have been developed from interspecific seed glucoraphanin concentrations varied significantly among inbreds. crosses of PI 199947 and A 19182 with B. oleracea to introgress black Overall, concentration for a given inbred was relatively similar across rot resistance from related species. Inoculation of plants with black rot all four environments. One doubled haploid had the highest mean seed revealed segregation distortion of a black rot resistance gene derived glucoraphanin concentration at 70.4 µmole/gdw across all environments, from B. carinata accession PI 199947 that was confirmed with linked and a conventional inbred from an open-pollinated population had RAPD markers. Segregation distortion does not appear to be related to the next highest at 61.9 µmole/gdw. Two doubled haploids had mean gametic inviability or aneuploidy, but may be related to chromosomal seed glucoraphanin concentrations less than 10 µmole/gdw across all instability. Inoculation of juvenile and mature plants also revealed dif- environments, while the remaining inbreds were intermediate. Results ferential responses to wound and spray inoculation procedures with indicate that observed genetic variation was more important than the several commercial cabbage varieties exhibiting high levels of tolerance environmental variation in determining glucoraphanin concentration in to black rot in field spray inoculation trials while being susceptible broccoli seed produced in these trials. It appears that development of self- to seedling wound inoculations. Breeding lines developed from PI compatible inbreds that combine consistent high yield and high glucora- 199947 were evaluated with commercial cabbage varieties to determine phanin should be readily accomplished though inbreeding and selection. responses to wound/spray inoculations and the practicality of using this germplasm in commercial breeding programs. 2:30 RAPD Analysis for mtDNA of OguCMS and its Maintainer in Non-heading Chinese Cabbage 2:00 Variability in Lutein and Beta-carotene Accumulation Gong-Jun Shi1, Xi-Lin Hou2, Zhongchun Jiang*3 Among Leafy Brassica oleracea Cultigens 1Horticultural College, Nanjing Agricultural University, Tongwei Road 1 2 Dean Kopsell* , David Kopsell 1#, Nanjing City, Jiangsu Province, 210095, People·s Republic of 1Plant Biology, The University of New Hampshire, G48 Spaulding China, 2Horticultural college, Nanjing Agricultural University, Tongwei Hall, 38 College Road, Durham, NH, 03824, 2Plant Biology, The Road 1#, Nanjing city, Jiangsu Province, 210095, People·s Republic of University of New Hampshire, G37 Spaulding Hall, 38 College China, 3plant science, state Univ.of New York, Cobleskill,NY 12043, Road, Durham, NH, 03824 New York, 12043 Green leafy vegetables crops are important sources of dietary ca- RAPD analysis was employed to study the mtDNA of OguCMS and rotenoids and kale (Brassica oleracea L. var. acephala) ranks highest its maintainer in non-heading Chinese cabbage. Results showed much among all vegetables for reported levels of lutein and beta-carotene. difference appeared between the OguCMS and its maintainer. Two fi fi fi Twenty-three B. oleracea cultigens, including kale, were eld grown speci c mtDNA fragments OPAF121200and OPAF12900 were ampli ed

under similar fertility over two separate years and evaluated for leaf from OguCMS and one fragment OPAF122000 from its maintainer. lutein and beta-carotene accumulation. Choice of B. oleracea cultigen Further study was conducted to prove its relation with the fertility. and year significantly affected both lutein and beta-carotene accumula- tion in leaf tissues. Lutein concentrations ranged from a high of 13.43 2:45 Resistance to Soilborne Tombusviruses Within Lactuca mg per 100 grams fresh weight for B. oleracea var. acephala Toscano Sativa: Genetic Control, Mechanisms, and Potential for to a low of 4.84 mg per 100 grams fresh weight for the USDA ac- cession B. oleracea var. acephala 343-93G1, representing a 2.7 fold Reliable and Long-Term Disease Control increase across cultigens. Beta-carotene accumulations ranged from Rebecca Grube*, Edward Ryder, William Wintermantel, a high of 10.00 mg per 100 grams fresh weight for B. oleracea var. Rami Aburomia acephala Toscano to a low of 3.82 mg per 100 grams fresh weight U.S. Dept. of Agriculture, ARS, 1636 E. Alisal St., Salinas, CA, 93905 B. oleracea acephala for var. 30343-93G1, representing a 2.6 fold At least two tombusviruses, tomato bushy stunt and lettuce necrotic fi increase across cultigens. Cultigens grown in year 2 displayed signi - stunt viruses, cause the disease lettuce dieback. In commercial lettuce cantly higher carotenoid values than year 1, but rank order among the fields in California and Arizona, symptoms have been observed only cultigens for both lutein and beta-carotene did not change between on romaine and leaf lettuce cultivars, but never on modern crisphead the years. During each year there were high correlations between (iceberg) cultivars. Over 100 Lactuca sativa cultivars and plant intro- B. ol- leaf carotenoid and chlorophyll a and b pigments. Choice of duction (PI) accessions were evaluated for resistance in field experi- eracea fl cultigen appears to in uence carotenoid accumulation, which ments. Consistent with observations in commercial fields, all modern

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crisphead cultivars were asymtomatic (resistant) and all modern romaine (‘Sunrise·) was also available. Breeding goals were to develop plants cultivars were susceptible. Both resistant and susceptible accessions with earlier flowering, more compact growth, bigger flowers, long were identified among modern leaf lettuce cultivars, heirloom crisphead blooming period and outstanding performance as bedding plants or cultivars, and romaine-like PI accessions. The romaine PI 491224 was in hanging baskets. Breeding methods have included multitrait selec- used in the development of resistant romaine breeding lines (Grube tion, polyploidization and interspecific hybridizations. Selection cycles and Ryder 2003). Focusing on the modern crisphead cv. Salinas and are initiated under artificial lighting in the greenhouse during fall and PI 491224, both of which fail to develop symptoms in infested fields, winter months. During summer, selected lines are trialed in the field our objectives were to determine the inheritance of resistance and to and as outdoor and greenhouse hanging baskets. In Spring 2002 the assess whether the viral pathogen systemically infects asymptomatic first two cultivars developed at UNH were released: ‘Wildcat Blue·and plants under field and laboratory conditions. Preliminary data sug- ‘Wildcat Orange·. We have also obtained breeding lines with pink and gest that resistance in PI 491224 is conferred by a dominant allele at violet flower colors. Currently, other Anagallis breeding lines are under a single locus. We will discuss the implications of our results on the industry trials with the goal of releasing cultivars with other flower colors. potential for the long-term control of lettuce dieback through the use The inheritance of flower color in A. monelli is being studied. Based of resistant cultivars. on pigment analysis of blue, orange and red anthocyanins and genetic segregation data, we propose a three-gene model determining flower 1:30 pm–3:15 pm ORAL SESSION 6 557 color in this species. Research is in progress to test this hypothesis with populations developed using diploid blue and orange wild accessions Ornamental Plant Breeding of A.. monelli collected in Southern Europe. Moderator: To be announced 1:30 Molecular Genetic Components of Inflorescence Archi- 2:00 The Ornamental Plant Germplasm Center—Ranking tecture in Buddleja Priority Genera For Conservation Jeffrey A. Adkins*, Dennis J. Werner David Tay* Horticultural Science, North Carolina State University, Campus Box Ornamental Plant Germplasm Center, The Ohio State University, 670 7609, Raleigh, NC, 27695-7609 Tharp Street, Columbus, OH, 43210 Rapid progress has been made over the past decade in understand- The Ornamental Plant Germplasm Center (OPGC), the new US ing the molecular genetic control of meristematic phase change and National Plant Germplasm System (NPGS) repository at The Ohio State inflorescence development. Several pathways for floral induction and University is mandated to conserve, evaluate and distribute herbaceous development have been extensively characterized in model plant ornamental plant germplasm. It is the first specialized genebank for species. These findings provide increased insight into the molecular flowers in the world. The center·s mission, goal and objectives have genetic components of inflorescence diversity. Buddleja, a cosmopolitan been formulated, presented and approved by the US Department of taxon of roughly 100 species, provides a unique model for studying Agriculture, floriculture industry and academia following its official inflorescence development at the molecular level. Great diversity in inauguration in July 2001. Herbaceous ornamentals consist of many inflorescence architecture exists among Buddlejaspecies, and numerous genera and species and one of OPGC key tasks is the prioritization hybrids exist between and among many of these taxa. Breeding goals of plant genera for conservation. The center works in consultation have included the enhancement of floral architecture through increased with the NPGS Herbaceous Ornamental Crop Germplasm Committee panicle branching and total flowers per inflorescence. Homologues of (HOCGC) on this. The HOCGC in 1995 proposed the first list of 24 floral meristem identity genes FLORICAULA (FLO) and LEAFY (LFY) priority genera and was superseded by a second list of 48 genera from from Antirrhinum majus and Arabidopsis thaliana have been isolated a survey among HOCGC members in 1999. The current priority genera from B. davidii ‘Nanho Purple·(2n = 4 × = 76) and B. lindleyana (2n = 2 list effective from 2001 includes thirty genera as follows: Aglaonema, × = 38). A Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) Alstroemeria, Anthurium, Aquilegia, Aster, Baptisia, Begonia, Cam- technique was used to isolate partial internal cDNAs of putative homo- panula, Chrysanthemum (Dendranthema), Dianthus, Dieffenbachia, logues from total RNA extracted from young developing inflorescences. Euphorbia (Poinsettia), Geranium, Hemerocallis, Impatiens, Iris, Lilium, Additional DNA sequences corresponding to the 5·- and 3· – ends of Narcissus, Pelargonium, Petunia, Phalaenopsis, Philodendron, Phlox, the coding regions were isolated by Random Amplification of cDNA Rudbeckia, Salvia, Spathiphyllum, Tagetes, Verbena, Veronica and Ends (RACE). DNA sequences representing the coding regions of B. Viola. Together they represent some 6,692 species based on Hortus davidii and B. lindleyana homologues show strong sequence identity Third (1976) and thus too many taxa for a new center to handle. It was with FLO and other FLO/LFY homologues. FLO/LFY homologues decided at the 2001 HOCGC meeting to rank them. Eight criteria were exist as single copy genes in most other plant species. Three unique used to score the degree of importance in term of germplasm conserva- coding sequences have been identified in B. davidii and B. lindleyana tion and commercial value. The questionnaire was distributed to the representing at least two gene copies each. Deletions in the coding current 37 HOCGC members from the floriculture industry, universi- sequences from both taxa are consistent with other FLO/LFY homo- ties, USDA and botanic gardens, and 16 responses were received. The logues. Additionally, B. lindleyana transcripts are shorter than B. davidii questionnaire was also sent to the industry by OFA An Association of transcripts. However, no deletions within functional domains were found. Floriculture Professionals and 13 responses were returned. Weighed means were used to handle missing values and to take care of differences 1:45 Breeding and Studies of Flower Color in Anagallis monelliL. in scoring level between responses. The HOCGC and non-HOCGC group were analyzed separately and then combined together. The top 1 2 Rosanna Freyre* , Robert J. Griesbach fifteen genera in descending order are as follows: Begonia, Impatiens, 1Plant Biology, University of New Hampshire, G36 Spaulding Hall, geranium (referring to Pelargonium), Petunia, Salvia, Pelargonium, Durham, NH, 03824, 2U.S. Dept. of Agriculture, Floral and Nursery Viola, Dianthus, Campanula, Hemerocallis, Alstroemeria, Lilium, Plant Research, Agricultural Research Service, BARC-West, Bldg. Verbena, Rudbeckia and Phlox. 010A, Beltsville, 20705 Breeding of Anagallis monelli (Blue Pimpernel) was initiated at 2:15 Breeding New Chilean Bulb Species UNH in 1998. A.. monelli is an annual plant of Mediterranean origin with beautiful blue flowers and trailing habit. In 1998, only one blue Mark Bridgen* cultivar (‘Skylover Blue·) was grown commercially. Although attrac- Department of Horticulture, Cornell University, 3059 Sound Ave. tive, ‘Skylover Blue·is very leggy (long internode length) and flowers LIHREC, Riverhead, New York, 11901 later than desired for spring sales. A cultivar with small orange flowers Along-term breeding project with several Chilean geophytes began

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in 2002 at Cornell University. The genera that are being investigated Fifteen bulbs were obtained from each of eleven sources. Bulbs were

are Conanthera, Rhodophiala, Leucocoryne, Pasithea, Zephyra, and potted, rooted at 21 °C for 2.5 weeks, vernalized at 4 °C for 6 weeks, FRIDAY Alstroemeria. All species, except Alstroemeria are new to the breed- and then grown at 21 °C in a randomized complete-block design. Data ing program. Alstroemeria has been hybridized for the past 18 years were collected on days to soil emergence (DSE) after vernalization, with 5 patented cultivars released. This presentation will describe days to visible bud (DVB), flower bud number (FBN) and node number the procedures that are involved when beginning a new breeding (NN). DSE, DVB, FBN, and NN varied significantly among growers; program. These genera are long-term breeding projects because the 5–24, 50-68, 4.3–7.1, and 83-104 respectively. Difference between bulbs, rhizomes, and corms that are involved can take three to five years DSE and DVB was not significantly different among growers (P = to flower from seed. In addition to traditional breeding techniques, 0.26), and DSE and DVB were highly correlated (r2 =0.88). DSE and in vitro procedures are being developed to hasten the growth of the FBN were negatively correlated (r2 = –0.54). DSE appears to be the geophytes and to subsequently increase the speed of flowering. Embryo primary factor for variable greenhouse forcing. culture procedures for these geophytes will be discussed. 3:00 Chromosome Counts in Eleven Populations of Gaura coc- 2:30 History of Ornamental Peach Cultivation and Develop- cinea Pursh. ment in China Grace Pietsch*, Neil Anderson 1 2 3 Dongyan Hu* , Zuoshuang Zhang , Donglin Zhang , Horticultural Science, University of Minnesota, 1970 Folwell Avenue, Qixiang Zhang4 St. Paul, MN, 55108 1Horticulture Department, Beijing Botanical Garden, Wofosi Road, Bei- Gaura coccinea is the most complex species of the genus Gaura, jing, 100093, People·s Republic of China, 2Director, Beijing Botanical ranging from diploid (2n=2x=14) to octaploid (2n=8x=56), with the Garden, Wofosi Road, Beijing, 100093, People·s Republic of China, most common forms being tetraploid (2n=4x=28) and hexaploid 3Department of Plant, Soil, and Environmental Sciences, University of (2n=6x=42). G. coccinea is an herbaceous perennial that occurs Maine, 5722 Deering Hall, Orono, Maine, 04469-5722, 4Department of naturally from British Columbia through central United States and landscape Horticulture, Beijing Forestry University, Haidian District, Mexico, and is being used in the breeding program to introgress Xiaozhuang, Beijing, 100083, People·s Republic of China winter hardiness into G. lindheimeri, a commercial diploid species. G. Ornamental peach (Prunus persica (L.) Bastch) originates from coccinea populations have been collected in Minnesota (n=6), Texas China. Over 3000 years ago, there were records of cultivated peach in (n=3), and California (n=2). A total of 32 genotypes were included in Chinese poetry. From Han Dynasty (B.C. 206–A.D. 220), peach was this study. The objectives of this research are to determine the ploidy grown in the gardens as an ornamental plant and there were 7 cultivars level of the different populations and the correlation between ploidy could be found in the writing record. Since then, this beautiful early level and phenotype. Root tips were collected from cuttings of each spring bloom plant brought a lot of attentions in China and became the genotype, fixed in 1:3 propionic acid : ethanol, stained with Shiff·s symbol of luck and happiness. Cultivation of ornamental peach began reagent, and examined using light microscopy. Chromosomes within from Shanxi and Gansu, one group eastward to Hebei, Henan, and five cells per genotype were counted. Four phenotypic traits were Shandong, along the Yellow River, then southward to Hangzhou and recorded for each genotype: flower size (n=5, diameter at widest Shanghai, then continued southward to Guangzhou, Taiwan; Meanwhile, point), plant habit (upright or spreading), plant height (soil to base another group southward to Hunan and Sichuan. During Qing Dynasty of inflorescence), and leaf l/w ratios (n=5). Results showed that the (1644–1911), Ornamental peach had been widely cultivated in China populations from Minnesota were tetraploid (2n=4x=28). Once chro- and many new cultivars were developed from the different climatic mosome numbers were verified in all MN, TX, and CA populations, zones and habitats. Hangzhou and Shanghai had 21 cultivars, which phenotypic trait data was correlated with the different ploidy levels. belonged to the different phenotype compared to the cultivars in Beijing. Based on the results of this study, diploid G. coccinea will be selected Today, 60 ornamental peach cultivars are preserved in the 10 different for interspecific hybridization with G. lindheimeri. However, it will locations in China. Beijing Botanical Garden hosts the best ornamental be necessary to create a tetraploid G. lindheimeri to introgress winter peach collection with 55 cultivars and more than 5000 individual plants. hardiness from tetraploid Minnesota populations. These collections are great resources for further studies on ornamental peach biological characteristics, environmental impact, genetic diver- 1:30 pm–3:30 pm WORKSHOP 4 552A sity, breeding, and utilization, which will enhance ornamental peach popularity in the gardens worldwide. Proprietary Issues Concerning New Fruit Cultivars Moderator: M. Elena Garcia 2:45 Somaclonal Variation Among Lilium longiflorum ‘Nellie Sponsor: Pomology Working Group (POM) White· Bulb Grower Sources David Zlesak*, Neil Anderson Objective: To address legal and practical issues concerning the testing of new fruit cultivars given the limitations associated with Horticultural Science, University of Minnesota, 1970 Folwell Ave., St. Paul, MN, 55108 the interpretation the plant patent law. Easter Lily (Lilium longifl orum) is a unique crop in North America Summary: Future testing of fruit cultivars is in jeopardy because of because there is a limited number of bulb growers in a narrow geo- the interpretation of the plant patent law. How are legal and practical graphical region, one predominant clone (‘Nellie White·), and no issues being resolved by breeders while trying to protect program central propagator. Each of the ten major bulb growers maintain their objectives and organizational policies, and the effect of these solu- own somaclonal selection of ‘Nellie White· and over time variability tions on testing new cultivars by researchers will be adressed. accumulates. Each decade, growers put a new somaclonal selection of ‘Nellie White· into production originating from one plant selected To Whom Do the Fruits Belong? An Introduction to for superior performance. Bulb producers tend to select late emerging the Workshop Discussion on the Impact of Proprietary somaclonal variants to avoid spring hail storms. Somaclonal selection Rights on the Fruit Industry has led to divergence among bulb producers and variable forcing Curt R. Rom* characteristics for greenhouse finishers. Greenhouse finishers typically Dept. of Horticulture, University of Arkansas, Fayetteville, AR, 72701 purchase bulbs from multiple growers to account for variability and ensure a salable crop. The objective of this research is to document Fruit crops in the US have been proprietorially protected with patents somaclonal variability among bulb growers for greenhouse forcing. and/or trademarks for more than a century. However, in the past few

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decades, the number and rate at which new cultivars are protected by plant field. This model shows promise in lowering management costs while patents and trademarks has dramatically increased. Although previously maximizing the realized royalty revenue for varieties that may only have patented or trademarked plants were widely available to the growing pub- niche market or low acreage potential. In contrast, the breeders of seed lic, this is changing significantly. The protection of fruit crops, although crops at Cornell utilize a combination of material transfer agreements providing protection of ownership may be creating impedance to tech- (MTAs), plant variety protection (PVP) and utility patents to protect nology development and use of new cultivars. The following workshop varieties and germplasm. These can provide long-term protection for presents discussions of pros and cons of proprietary ownership, the pro- germplasm transferred to other public or private breeding programs, tection of new fruit cultivars, and who will benefit from those protections. for new varieties, and for novel traits developed in individual crops. While PVPs are not granted for asexually propagated crops, public fruit Working with Plant Breeders· Rights and Plant Patent breeding programs have utilized MTAs and utility patents to some extent Regulations in Tree Fruit Breeding Programs to protect fruit varieties or germplasm. Cornell fruit breeders to date David M. Hunter* have not utilized MTAs or utility patents, but restrictive test agreements Agriculture and Agri-Food Canada and University of Guelph Depart- are used in some fruit breeding programs to retain and control breed- ment of Plant Agriculture Vineland Station, Ontario, Canada L0R 2E0 ing rights. In addition, MTAs and utility patents may become part of The AAFC tree fruit breeding programs formerly located at Harrow, the future model for protecting germplasm and varieties developed in Ontario, have resulted in the introduction of several new cultivars of pear, Cornell·s fruit breeding programs. It is clear that the heyday of public funding for public plant breeding programs is long past. Regardless of peach, nectarine and apricot. Prior to the Canadian Plant Breeders·Rights Act of 1990, new cultivars were introduced and released into the public the model used, it is increasingly necessary for public breeding programs domain. Cultivars introduced since 1990 have been subject to protection to generate direct revenue that can be attributed to the program. This and commercialization through contracted agents in North America and is required to replace traditional funding sources and to validate the relevance of such programs to university administrators. Unfortunately, Europe. The Plant Breeders·Rights Act also necessitated changes in the process of second test and grower evaluations, requiring tighter controls this process will increasingly restrict the free flow of ideas, germplasm, over plant materials during the evaluation of advanced selections. Alter- and cooperation between the relatively few public breeding programs natives to our current practices (presently under review) will be discussed. still operating at universities in the U.S. This will create an ever more difficult landscape through which these programs will have to navigate Plant Patent Perspectives from Cornell Fruit Breeding in order to be successful. The long-term effect will inevitably be a reduc- Programs tion in the productivity of public breeding programs and increase in the Courtney A. Weber* privatization of the germplasm resources for fruit breeding in the U.S. Department of Horticultural Sciences, Cornell University, New York 1:30 pm–3:30 pm WORKSHOP 5 555B State Agricultural Experiment Station, Geneva, NY 14456; Public plant breeders are increasingly under pressure to realize Engaging the Online Learner with Multimedia direct financial value from the products of their programs. Continued Presentations reductions in support for public breeding programs from traditional state and federal sources have increased the need for alternative sources of Chair: Tim Rhodus funding. Cornell University s fruit breeding programs began using plant · Sponsors: Teaching Methods Working Groups (TCHG) and patents to protect intellectual property and generate alternative funding Computer Applications in Horticulture (COMP) sources since the early 1980·s. The Cornell model for managing patented fruit varieties was initially set up as a collaborative effort between the Objective:Online learning and web-assisted courses provide students inventor/breeder and the New York State Fruit Testing Cooperative the opportunity to acquire information, expand their understanding Association and more recently the Cornell Research Foundation (CRF). of concepts, and interact with others. However, the great majority Royalties for plants sold were split between the breeder, CRF, the of online content is being presented as “virtual” textbooks or lecture affiliated academic department of the inventor/breeder, and Cornell s · notes. As such, the learner is merely reading the information. As a College of Agriculture and Life Sciences. This model consists of plant patents to protect varieties and open licensing to nurseries in the U.S. way of engaging learners and increasing their knowledge, several Licensing of patented varieties outside the U.S. has usually been ac- technologies exist for creating multimedia presentations or nar- complished through exclusive or semi-exclusive licensing with nurseries rated slide shows. This workshop will demonstrate the use of video or marketing companies by country or region with the potential for sub- presentations and narrated slide shows for creating online tutorials, licensing. The small fruits program, mainly strawberries and raspberries, lectures, and problem-solving guides. An emphasis on reusable has been successful in generating significant royalty income using this learning modules and managing digital assets is critical to this type model due to high density and short term production systems utilized of communication. Software options for content management and in these crops. The apple, grape, and stone fruit breeding programs delivery will be presented. have seen limited success in generating meaningful funding using this model, mainly due to the long-term production systems for these crops Summary: Multimedia presentations engage students and improve but also because of rising legal costs associated with patent applica- their ability to acquire information and learn new concepts. This tions. This has prompted modifications and innovations in the model workshop will demonstrate the use of presentations and slide shows used for protecting varieties to increase the potential royalty revenue for creating online tutorials, lectures, and problem-solving guides. and decrease the costs associated with management of the varieties. Software options for content management, presentation creation, Modifications include exclusive and semi-exclusive licensing within the and online delivery will be covered. U.S. targeted at marketing companies or larger nurseries to maximize the exposure and availability of new varieties per management dollar Experiences at Texas A&M with Video Presentations spent by CRF. This is much the same model used abroad and allows Dan Lineberger* for easier tracking and control of a patented variety while maintaining Dept. of Horticultural Sciences, Texas A&M University broad distribution among producers. Additionally, in some instances the plant patent approach has been abandoned in favor of licensing the Experiences at Ohio State with Synchronized right to use variety/intellectual property directly from Cornell without Multimedia Presentations transfer of ownership. Nurseries and growers alike are required to Tim Rhodus* sign agreements granting the right to grow the variety, yet Cornell Dept. of Horticulture & Crop Sciences, Ohio State University University retains the ownership of the plant itself even in the grower·s

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1:30 pm–3:30 pm COMMITTEE MEETING 556B anthocyanins were absent and cells appeared dead in unhealthy (buck- FRIDAY pm HortTechnology Editorial Board skinned) periderm. These data suggest that 1) calcium concentration of the periderm influences the anthocyanin concentration and visual color Chair Neal E. De Vos of ‘Dark Red· Norland tubers, 2) application of supplemental calcium increases the anthocyanin content of red tuber skin, and 3) there is a 1:30 pm–4:00 pm ORAL SESSION 7 551A potential for reducing the incidence of buck skinning in red tubers by Environmental Stress Physiology in season application of calcium. Moderator: Jiwan Palta 2:00 Effect of Soil- and Foliar-applied Calcium Chloride on Pear 1:30 Analysis of Blueberry ESTs from cDNA Libraries of Cold Tolerance to Brown Spot (Stemphylium Vesicariium) Acclimated and Non-acclimated Flower Buds Moreno Toselli1, Bruno Marangoni*2, Donatella Malaguti3, Anik Dhanaraj, Lisa Rowland*, Janet Slovin Graziella Marcolini1, Elena Baldi1 Fruit Laboratory, Bldg 010A, USDA/ARS, 10300 Baltimore Ave., 1Dipartimento di Colture Arboree, University of Bologna, viale Fanin, BARC-West, Beltsville, MD, 20705 46, Bologna, Italy, 40127, Italy, 2Dipartimento di Colture Arboree, Environmental stresses, including low temperature extremes, University of Bologna, viale fanin, 46, Bologna, Italy, 40127, Italy, reduce crop yields and impact the profitability and competitiveness of 3Dipartimento di Colture Arboree, University of Bologna, Viale Fanin, U.S. producers. The U.S. is the world·s leading blueberry producer, 46, Bologna, Italy, 40127, Italy but the blueberry industry suffers from a lack of winter hardy and Brown spot (Stemphylium vesicarium) is one of the most important spring-frost resistant cultivars. Our laboratory has been studying disease of pear causing, in susceptible cv like Conference and Abb¨¨ genetic and molecular aspects of cold hardiness in blueberry in order Fetel, heavy losses of yield. The scarce effectiveness of chemical control to identify markers/genes associated with this trait. Marker-assisted along with the increasing demand for sustainable orchard management selection or transgenic approaches based on such markers or genes drive research toward integrated control strategies. Recently, it was can be used to develop cold hardy cultivars that can be grown in a shown a positive effect of soil salinity on pear resistance to fire blight wider geographical range. Currently, we have undertaken a genomics (Toselli et al., 2002), although it was not clear if this effect was related project involving partial sequencing of cDNA clones from cold accli- to leaf osmoregularity or to a decreased tree water potential. The aim fl mated and non-acclimated ower buds to identify and compare genes of this study was to assess the effectiveness of soil and foliar-applied expressed under both conditions. So far, about 600 cDNA clones from CaCl2 in lowering pear susceptibility to brown spot. Two-year old potted each of these libraries have been sequenced from the 5 ends and most pear tree, cv Abb¨¨ Fetel/Quince C were treated, according to a com- fi of the clones have been putatively identi ed based on their similarity plete randomized design (5 replicates), as it follows: 1) untreated, well to sequences in Genbank. Assembly of individual ESTs into clusters –1 watered control 2) soil-applied solution of 5.6 g·L of CaCl2 (electric of sequences representing unique transcripts has been performed using – 1 conductivity of 8.3 mS·cm ) 3) foliar-applied (once a week) CaCl2 contig assembly software. Contigs representing ESTs with putative at a concentration of 7.35 g·L–1 (2 g·L–1 of Ca). Soil treatments were fi protein identities are being classi ed into ~12 functional groups and applied twice a week by returning the whole evapo-transpirated of tap the percentages of clones that fall into each category determined for water or saline solution. After 6 weeks of treatments (on June 14), trees fl each library. About 200 of the clones from the cold acclimated ower were enclosed in a chamber of plastic film to increase relative humid- bud library have been sequenced from the 3 ends as well as the 5 ends ity and inoculated at sunset by spraying a S. vesicarium suspension (2 and PCR primers developed based on their 5 and 3 sequences. Primer ×10000 conidia/mL) on the leaves. Plastic chamber was removed the pairs have been used to develop EST-PCR markers that are useful for following morning and 21 days after experimental inoculation, leaves fi DNA ngerprinting and mapping in blueberry. and fruits were harvested to determine brown spot incidence both as a percentage of infected leaves and as a number of necrotic spot per 1:45 Calcium Improves Skin Health and Color of ‘Dark Red fruit. Before inoculation stem water potential (_·w) and leaf osmotic Norland· Potato (Solanum tuberosum L.): Localization of potential (_·s) were measured from 1 leaf per tree on May and June. Color in Intact Cells Soil salinity was also measured from a 100-g-soil sample. Ten g of fruit fresh weight (including peel) and 1 g of leaf FW were used to detect the Anne Reis, Jiwan Palta* following fractions of Ca: soluble, water soluble salts of organic acid, Department of Horticulture, University of Wisconsin-Madison, 1575 pectate, triphosphate, oxalate, and residual (Mostafa and Ulrich, 1976). Linden Dr., Madison, WI, 53706 While increasing soil salinity, soil-supplied CaCl2 decreased stem _·w, Calcium is known to be deficient in potato tubers and research from total number of leaves, total number and percentage of infected leaves. our group has shown that tuber quality can be improved by changing Number of necrotic spots per fruit was unaffected by treatments. Only

tuber calcium levels. In season calcium applications were made to plants Ca-oxalate was higher in trees treated with foliar CaCl2. Fruit total Ca of ‘Dark Red·Norland potato (Solanum tuberosum L.) to determine the ranged between 169 and 194 mg·kg–1 FW. Fractions of leaf Ca were effect of calcium application on color and anthocyanin concentration not affected by treatments and total leaf Ca ranged between 4549 in and visual appearance of buckskinning. In addition, tuber periderm control and 5385 mg·kg–1 FW in soil-applied trees. Unlike leaf total sections were viewed under a microscope to determine the location Ca, Ca-triphosphate was linearly and negatively related (r = 0.64*) to of anthocyanins in the periderm. Application of calcium increased the percentage of infected leaves, however in both leaf and fruit, residual-Ca tuber periderm calcium concentration by 10% over the control. Cal- was best related (R2 = 0.85 and 0.69, respectively) to disease resistance, cium application also increased visual color and increased anthocyanin according to a quadratic relationship. Stem _·w and leaf _·s were not concentration in the periderm by 22%. Paired measures of calcium related to the incidence of the disease. Calcium appears to be positively concentration and anthocyanin concentration were made on individual involved in pear tolerance to brown spot, and its effect is more detectable tubers from calcium treated tubers and control tubers to determine the on leaves than fruits. Among different fractions, residual-Ca seems to relationship between tuber calcium and anthocyanins. Linear regres- be the best correlated to the brown spot tolerance. sion analyses showed that calcium concentration and anthocyanin concentration were positively correlated and that calcium application 2:15 Effects of Heat Stress on Antioxidases and Superoxide Anion increased the slope of the regression line by 35%. Buckskinning was in Seven Summer-Flowering Chrysanthemum Cultivars significantly reduced in calcium treated tubers after three months of storage. Magnified periderm sections showed that anthocyanins were Weiming Guo*1, Heling Song1, Zhongchun Jiang2 located in the cell sap and cell walls of healthy periderm, whereas 1College of Horticulture, Nanjing Agricultural University, No.1 Wei- gang, Nanjing, 210095, People·s Republic of China, 2Dept. of Plant Sci- HORTSCIENCE, VOL. 38(5), AUGUST 2003 681

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ence, State Univ. of New York, 116 Hodder Hall, Cobleskill, NY, 12043 pieces from natural populations in Texas and Missouri and from plants Metabolism of membrane-lipid peroxides and oxygen derived free native to Missouri and Arkansas that have been cultivated in northern radicals as well as changes of antioxidases in seven summer-flower- Illinois. TTC (2,3,5-triphenyl tetrazolium chloride) staining of cortex ing chrysanthemum cultivars were studied. The heat-tolerant cultivars and phloem was compared with discolouration of the same tissues to produced less MDA, had a lower superoxide anion production rate, determine hardiness levels. There was a strong correlation between

and displayed higher activities of POD and SOD. In the heat-tolerant the two assays; however, in some cases the critical temperature (T50) cultivars, the accumulation of superoxide anion under heat stress stimu- identified by the TTC method was 5 °C lower than for discolouration.

lated SOD activity, which was not observed in heat-intolerant cultivars. Although T50 for samples from Texas was –20 °C on 2 Dec. 2002 and

–35 °C on 21 Jan. 2003, T50 for samples from Missouri and Illinois was either the lowest temperature tested (–35 °C and –60 °C in December and 2:30 Evaluation of Common Bean Yield Components under January, respectively) or was below the tested range. Plants of Leitneria Heat Stress fl oridana appear to tolerate temperatures well below those found in Katy Rainey*1, Phillip Griffiths2 native habitats. While this indicates that the species could survive in 1Horticultural Sciences, Cornell University, Cornell University NY- diverse climates, provenance differences in cold hardiness should be SEAS, 303 Hedrick Hall, 630 West North Street, Geneva, NY, 14456, considered when selecting plants for use in landscapes. 2Horticultural Sciences, Cornell University NYSAES, 630 West North Street, 302 Hedrick Hall, Geneva, NY, 14456 3:00 Major Factors Influencing Year to Year Variation of Yields Yield reduction due to heat stress in common bean (Phaseolus in Sao Paulo, Brazil Citrus vulgaris L.) is important in temperate production areas experiencing L. Gene Albrigo*1, Juan Valiente2, Carlos Van Parys de Wit3 brief and problematic seasonal heat waves and tropical production areas 1 where high temperatures restrict bean cultivation both geographically Citrus Research & Education Center, University of Florida, 700 Experi- 2 and temporally. Yield components of 24 common bean genotypes were ment Station Rd., Lake Alfred, FL, 33850, Citrus Research & Education evaluated following exposure to four different greenhouse temperature Center, University of Florida, 700 Experiment Station Rd., lake Alfred, 3 treatments during reproductive development (night/day temperatures: FL, 33850, Production Department, Fazenda Sete Lagoas Agricola, 21/24 °C, 24/27 °C, 27/30 °C, 30/33 °C). Mean responses to high Bairro Martinho Prado, Mogi Guacu, Sao Paulo, 13840-970, Brazil temperature treatments included decreased seed number (49%), pod Year to year variation in yield can be more than 20% in Sao Paulo number (31%), and mean seed weight (25%). Seed number decreased State·s citrus industry. Drought during fruit set leads to excessive fruit in all genotypes; however, ‘G122·, ‘CELRK·, and ‘Brio· exhibited drop and is an important factor in decreasing fruit production in some reduced sensitivity (10%, 19% and 20% reductions in seed number, years. The influence of winter climate during flower bud induction respectively). The pod sets of heat susceptible genotypes ‘Labrador· is not well documented. Eight years of fruit per tree sample data for and ‘Majestic· were reduced under high temperatures (58% and 65%, both spring irrigated and non-irrigated blocks from four farms were respectively) while the pod sets of heat tolerant genotypes ‘HT38·and evaluated against weather data to determine the primary winter factors ‘Carson· were reduced minimally (0% and 5% respectively). ‘G122· involved in yield swings. Most of the winter period flower bud induction and ‘CELRK· set a higher number of pods as temperature increased; is presummed to be from drought stress induction. Even when blocks however, the interaction between yield components must be considered were irrigated during the fruit set period (the three months after bloom), as ‘CELRK·also exhibited a 35% reduction in mean seed weight. The fruit per tree variation followed the changes in statewide yields, even interaction between pod set and mean seed weight was a significant though most citrus in Brazil is non-irrigated. The fruit/tree values had component in reducing yield loss under heat stress. Yield stability is an an r2 of 0.42 to general yields for Sao Paulo State suggesting that factors important aspect of heat tolerance and was most consistent in ‘Brio·, other than spring irrigation play an important role in year to year varia- ‘CELRK·, ‘G122·, ‘HT20·and ‘Venture·. Understanding the responses tion. Evaluation of winter rainfall and cool weather periods identified of yield components to heat stress will enable more efficient selection of drought stress duration and cool weather periods following winter rains heat tolerant bean genotypes for reducing yield losses in growing areas. as factors that influenced yield potential. It was concluded that winter weather conditions during flower bud induction play an important role in determining the citrus crop level in Sao Paulo State in Brazil. 2:45 Germination and Low-temperature Tolerance of the Rare Leitneria floridana (Leitneriaceae) 3:15 Response of Carambola Trees to Four Moisture Levels in Jyotsna Sharma*, William R. Graves Calcareous Soil Horticulture Department, Iowa State University, 106 Horticulture 1 1 2 Hall, Ames, Iowa, 50011 Rashid Al-Yahyai* , Bruce Schaffer , Frederick S. Davies 1 Leitneria fl oridana, a rare shrub of the monotypic family Leitneria- Tropical Research and Education Center, University of Florida, 18905 2Horticultural Sciences, Uni- ceae, grows in mesic to wet habitats and is native mostly to the southern SW 280 St., Homestead, Florida, 33031, versity of Florida, PO Box 110690, Gainesville, Florida, 32611 United States. Its horticultural potential remains largely unexplored. We studied germination of seeds and cold hardiness of plants by sampling The effect of four levels of soil water on leaf gas exchange, stem some of the northernmost and southernmost populations of the species. water potential, vegetative and reproductive growth, yield, and fruit qual- When sown immediately after collection in June, ”5% of the intact, un- ity of mature field-planted and container-grown carambola (Averrhoa treated drupes from natural populations in Missouri and Florida produced carambola L. cv. Arkin) trees in calcareous limestone soil was studied. germinants. After storage, seeds were removed from the fruit or intact Soil water contents for field-grown trees were 100–92%, 91– 89%, 88– 86%, or 85–83% and for container-grown trees were 100– 79%, fruits were leached and then treated with gibberellic acid (GA3 at 750 mg/L). In the sample from Florida, germination occurred among 32% 78–69%, 68–50%, or 49–40% of soil water depletion as measured with and 24% of extracted seeds and seeds in leached drupes, respectively. multi-sensor capacitance probes. Plants in all treatments were irrigated Less than 5% germination was observed in treated seeds from Missouri after the preset soil water depletion level was reached. There were short-

and in untreated seeds from both locations. Post-emergence survival of term reductions in stem water potential and net CO2 assimilation when seedlings ranged from 60% (Florida) to 100% (Missouri). Chemical soil water content dropped below 89% for field-grown trees and 79% for inhibitors in tissues surrounding embryos, or physical properties of those container-grown trees. Re-irrigating stressed trees resulted in stem water

tissues, appear to inhibit seed germination. Physiological dormancy of potential and net CO2 assimilation returning to pre-stress levels. The

the embryo also likely contributes to the delayed germination of vi- short-term reductions in stem water potential and net CO2 assimilation were not sufficient to cause significant reductions in growth and yield. able seeds, and this may be overcome by a GA3 treatment. Laboratory tests were conducted to test midwinter low-temperature injury of stem

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3:30 Salinity Effects on Pepper Fruit Quality: The In- Need help interviewing for and getting the perfect job? Need FRIDAY pm volvement of Oxygen Radicals Production and the insight on what direction to take your career? Find out what Contradicting Effects of Calcium, Zinc, and Manganese resources are available to you. Beny Aloni*1, Leah Karni1, Asher Bar-Tal2 Topics include: 1Genetics and Vegetable Crops, ARO, The Volcani Center, POB 6, Bet- State of the job market Dagan, 50250, Israel, 2Department of Soil Chemistry, Plant nutrition What employers look for in prospective employees and Environmental Physiology, A.R.O. the Volcani Center, P.O.B. 6, Bet-Dagan, 50250, Israel Advice and inspiration for young graduates Irrigation of bell pepper (Capsicum annuum L.) crop with water Cold hard facts talk on job prospects and what it takes of high salinity reduces many aspects of fruit quality. It may increase to get in the door (and stay there!) Blossom-end rot, enhance fruit softening and cause premature ripen- ing. Previously it had been demonstrated that high salinity induces Tentative Speakers: oxidative stress in plant tissues. In the present study we show that bell Charles Riemenschneider* pepper fruits grown under high salinity contain high activity of oxygen Director Liaison Office: Washington, FAO radicals and of the radical producing enzyme–NAD(P)H oxidase. When incubated in vitro with pepper fruit pericarp discs, high NaCl concentra- Freddi Hammerschlag* tion (100–500 mM) caused an immediate production of oxygen radicals Research Plant Physiologist, USDA in concentration dependent manner. This effect was abolished by the Simon Hankins* NAD(P)H oxidase inhibitor DPI, indicating that NaCl was directly Research Manager, Acadian Seaplants affecting this enzymatic activity. Zinc and manganese (at 1 mM and to a lesser extent, calcium (at 3 mM), abolished oxygen radicals produc- Caula Beyl* tion in discs of control and of NaCl treated fruit pericarp. Magnesium Dir. of Institutional Planning, Research & Evaluation, Alabama A&M was not inhibitory in this system. Likewise, Zn, Mn, Ca, but not Mg, Lisa Ferns* inhibited NAD(P)H oxidase activity in vitro. The possible interactions Career Counseling Service, University of Rhode Island between these minerals in vivo and their effect on quality of salinity- grown bell pepper fruits will be discussed. 1:30 pm–5:00 pm COLLOQUIUM 1 Ballroom B/C

3:45 The Role of Anthocyanins in Senescing Leaves: Testing Bio-Derived Energy Sources for Protected Horticulture the Resorption Protection Hypothesis Moderator: Cary A. Mitchell William Hoch*1, Eric Singsaas2, Brent McCown3 Working Group Sponsor: Growth Chambers and Controlled En- 1Department of Horticulture, University of Wisconsin-Madison, 1575 vironments Working Group. The colloquium is co-sponsored by the Linden Dr, Madison, WI, 53706, 2Department of Biology, University following five working groups: Crop Physiology, Mineral Nutrition, of Wisconsin-Stevens Point, 1900 Franklin Street, Stevens Point, WI, Water Utilization and Management, International Topics of Concern 54481, 3Department of Horticulture, University of Wisconsin-Madison, to Horticulturists, and Waste Utilization in Horticulture. 1575 Linden Drive, Madison, WI, 53706 Co-organizers: Cary Mitchell, Purdue University; The capacity of anthocyanins to protect foliar nutrient resorption during senescence by shielding photosynthetic tissues from excess Corinne Rutzke, Cornell University. light (resorption protection hypothesis) was tested using wild-type Objectives: To inform ASHS members of emerging technologies and anthocyanin-deficient mutants of Vaccinium elliottii (Chapmn.). and opportunities to utilize alternative energy sources for horticul- Photosynthetic and nitrogen (N) resorption performances were compared tural production industries, especially those involving protected between and within three different environmental regimes during senes- horticulture, as we enter the 21st century and the U.S. government cence: an outdoor coldframe treatment; a high-stress treatment consisting adopts policies to move from a fossil-fuel-based economy toward of five days exposure to high light and low temperatures followed by transfer to a low-stress environment; and a low-stress treatment that a more bio-fuel-based one. Adoption of cheap, environmentally served as control to the two stressful treatments. Within the low-stress friendly crop-production technologies that deter global warming environment, mutant and wild-type plants were not significantly differ- and that use readily renewable, bio-based energy sources should be a priority goal for horticultural production industries, whose energy ent in photochemical efficiency (Fv/Fm) and N resorption performance during senescence. Within the coldframe treatment, a close relationship costs run anywhere from a third to over half of total production was observed between the biosynthesis of anthocyanins in senescing costs, depending on the degree of environmental control needed leaves of wild-type plants and significantly lower photochemical ef- (i.e., local climate and time of year), as well as degree of automation ficiencies in mutant plants. In the high-stress environment, wild-type utilized. The colloquium will enhance awareness by ASHS Members plants maintained higher photochemical efficiencies than did mutants. of emerging controlled environment production technologies and When transferred to the low-stress environment, wild-type plants were guide their development of research, instructional, outreach, and able to recover from the high-stress treatment, whereas mutant leaves dropped while still green and displayed symptoms of irreversible photo- business plans for the coming decade. oxidative damage. Nitrogen resorption of mutant plants in both stressful Summary: Fossil-fuel energy costs prevent controlled environment treatments was significantly lower than the wild-type counterparts. This agriculture (CEA) from providing quality, affordable horticultural work is part of the first experimental study supporting our resorption products to consumers year-round. Bio-based fuels represent poten- protection theory of anthocyanins in senescing leaves. tially cheap energy alternatives for CEA. Biogas piped from landfills can fuel heating/cooling of greenhouses and artificial lighting of 1:30 pm–3:30 pm STUDENT ACTIVITY 551B crops growing in warehouses clustered nearby. Anaerobic production

Career Planning Seminar of CH4 from feedlot waste or from composting of agricultural and Moderator: Jeff Norrie municipal wastes represents a renewable energy source for horti- Agricultural Research Manager, Acadian Seaplants Limited, 30 Brown cultural enterprises willing to locate in their immediate vicinity. The Ave., Dartmouth, Nova Scotia B3B 1X8 proposed federal Sun Grant Initiative for USDA, DOE, and land-grant

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universities to sponsor R&D will assist the transition to bio-based as well as treatment of wastewater and waste gases will be addressed. fuels and commodities. The diversity of bio-derived resources that Biographical Sketch:Chynoweth holds a bachelor·s degree in chem- can be converted into energy holds great promise to empower future istry and biology from the University of Louisville, and a master·s in horticultural CEA enterprises. environmental chemistry and biology and doctorate in environmental microbiology from the University of North Carolina. After postdoctoral The New Jersey Ecocomplex: Waste to Food Project study at the University of Florida and seven years on the faculty of the Harry Janes* Dept. of Environmental and Industrial Health at the University of Michi- Rutgers University gan, he became Assistant Director of Biotechnology and Environmental Research at the Institute of Gas Technology in Chicago. He is currently The mission of the NJ EcoComplex, a research center of Rutgers professor in the Agricultural and Biological Engineering Dept. and was University in southern New Jersey, is to develop solutions for busi- recently Deputy Director of the Environmental Systems Commercial ness and industry. The current research program emphasizes controlled Space Technology Center at the University of Florida. He is responsible environment agricultural production as well as new-use agriculture and for research and feasibility programs in the area of applied microbiol- aquaculture. One of the multi-dimensional innovative projects being ogy, with emphasis on production of methane and other chemicals from demonstrated at the EcoComplex is the waste to food project. The driving renewable resources, degradation of environmental pollutants, microbial force for this project is the landfill gas that operates four-30 kilowatt influenced corrosion, and indoor air quality. Chynoweth has co-authored microturbines. The microturbines provide heat and electricity for the over 130 technical publications, including one book and seven patents. greenhouse. Waste heat from the microturbines is also captured to run a desalinization unit, which produces freshwater that is then utilized in Energy Conversion Options for Energy-Efficient CEA: the greenhouse. Tilapia, a warm-water fish, is grown in recirculating Emphasis on Fuel Cells aquaculture tanks. The water is then filtered and used in the production of tomatoes that are grown hydroponically year-round. The tomatoes Norman R. Scott and fish are then sold to food distributors. By combining the two food Cornell University production systems, there is virtually no wastewater created or discharged One of the deterrents to the adoption of CEA on a broader scale is into the environment. The process also requires little to no pesticides. the significant cost of energy necessary for lighting and thermal environ- Each step of the process will be evaluated for its economic viability, mental control. Recent advances in energy conversion technologies such pollution prevention and application for landfills throughout the U.S. as microturbines and fuel cells offer the potential for combined heat and By combining these innovative, environmentally sound technologies power (CHP), which can be matched with the needs of CEA to reduced into an integrated system, this project demonstrates a sustainable pro- consumption of fossil-based fuels. Also, the potential introduction of duction technique for high quality, locally grown, fresh vegetables and CO2 from the energy conversion process offers an additional opportunity fish that is very energy efficient. It also reduces pollution by utilizing to enhance plant production. An assessment of microturbine and fuel the renewable landfill methane gas and avoiding emissions that would cell technologies for applicability to CEA will be a principal focus of otherwise be produced by electrical generating facilities. the presentation. Issues of energy efficiency, gaseous emissions, noise, Biographical Sketch:Janes is a research professor at Rutgers Univer- reliability and environmental impacts will be discussed. sity and has published extensively on environmental-plant interactions. Biographical Sketch: Scott is professor of biological and environ- He has worked in the area of value added agriculture, helping develop mental engineering at Cornell University. Scott was involved in bioen- agricultural businesses for high value specialty markets. Janes is also gineering research and teaching for over 20 years prior to spending 14 the director of the NJ EcoComplex, a consortium of university and years as a Cornell administrator. Since returning to the faculty in 1998, governmental partners focusing on research and technology transfer he has focused on research in sustainable development. with the goal of fostering economic development. Janes has spent his career working at the Cook College campus as a part of the New Jersey The “Sun Grant” Initiative Agricultural Experiment Station. Kevin Kephart* Renewable Biomethane from Land, Ocean, and Outer Dept. of Plant Sciences, South Dakota State University Space-energy Crops Land grant universities were initiated to develop programs in agri- cultural sciences and to support rural communities. Whereas a reliable, David P. Chynoweth* affordable, safe, and secure food system continues to be an important University of Florida asset for American society, need for a reliable, affordable, safe, and secure Production of methane via anaerobic digestion of energy crops and energy system is becoming increasingly evident. Many recognize that organic wastes would benefit society by providing a clean fuel from agriculture has a role in solving some of the nation·s projected energy renewable feedstocks. This could replace fossil fuel-derived energy and problems. The Sun Grant Initiative has been proposed to broaden the reduce environmental impacts, including global warming and acid rain. role that land grant universities play in their unique approach to higher Although biomass energy is more costly than fossil fuel-derived energy, education by implementation of a new program that will focus their trends to limit carbon dioxide and other emissions through regulations, efforts on renewable energy and biobased industries. The mission of carbon taxes, and subsidies of biomass energy would make it cost the Sun Grant Initiative will be to (1) enhance national energy security competitive. Methane derived from anaerobic digestion is competitive through development, distributiion, and implementation of biobased in efficiencies and costs with other biomass energy forms including energy technologies, (2) promote diversification and environmental sus- heat, synthesis gases, and ethanol. The objective of this presentation tainability of America·s agriculture through land-grant based research, is to review the results and conclusions of research on biomass energy extension, and education programs in renewable and biobased products, conducted under the sponsorship of the gas industry with periodic and (3) promote opportunities for biobased economic diversification in co-funding from other institutions. The scope of this program was rural communities. South Dakota University, Oklahoma State Univer- to determine the technical and economic feasibility of production of sity, the University of Tennessee–Knoxville, Cornell University, and substitute natural gas (SNG) from marine and terrestrial biomass and Oregon State University will serve as regional Sun Grant centers. The organic wastes using anaerobic digestion as a conversion process. Also regional centers will emphasize integrated research, extension, and discussed is the potential impact of this form of renewable energy on educational programs on renewable energy and biobased industries mitigation of carbon dioxide emissions from fossil fuels. More recently, based in rural communities. Sun Grant centers will engage with other the potential use of anaerobic digestion for stabilization of a recovery of land grant institutions and Department of Energy research laboratories nutrients from solid wastes during space missions has been studied with as well as a synergistic mechanism for technology transfer and higher funding from NASA. The application of this process for that function education for the benefit of a rural biobased economy.

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Biographical Sketch: Kevin Kephart is Associate Dean of the Col- the field trip destination and construct activities relating to the trip. FRIDAY pm lege of Agriculture and Biological Sciences and Director of the South Unfortunately, school budgets and time involved with pre-visits are Dakota Experiment Station. His academic home is Professor in the not always available. The integration of web-based pre-visits may be Department of Plant Sciences at South Dakota State University. He a more efficient alternative. The objective of this study was to com- is currently active nationally implementing the Sun Grant Initiative. pare the effects of traditional and web-based pre-visit activities on the This Initiative is aimed at broadening the land grant mission to include learning and attitude of fourth and fifth graders following a field trip research, extension, and teaching programs in ag-based renewable energy to a public garden. Each class was divided in half and assigned to one and biobased products. Kephart joined the faculty at South Dakota State of the pre-visit treatments. Seven open-ended questions were used to University in 1986, where his emphasis was a research and teaching evaluate cognitive responses. Twelve close-ended (Likert scale) ques- program in forage crop production and physiology. He received a Ph.D tions were used to evaluate attitudinal responses. Our results indicate in crop production and physiology from Iowa State University in 1987. that web-based pre-visit treatments significantly increased cognitive scores in students compared to the traditional pre-visit treatments. Two 2:30 pm–3:00 pm WORKING GROUP MEETING 550B advantages to the web-based pre-visit were 1) self-directed learning and 2) access to more visuals and information. While there were no Temperate Tree Nut Crops (NUTS) Working Group significant differences in attitudinal responses between treatments, the Chair: Patrick Conner overall attitudes of students in both treatments exhibited a willingness to learn and enjoy the field trip. This research can benefit public gardens 2:30 pm–3:30 pm COMMITTEE MEETING 554B by providing garden educators with another avenue of access to school Awards children and aid in creating suitable curricula. Chair: Fredrick A. Bliss 3:45 Comparing the Effectiveness of Independent Learning, 3:15 pm–4:15 pm COMMITTEE MEETING 554 A Traditional Learning, and Independent Web-based Learn- Leafy Vegetable Crop Germplasm Committee ing when Receiving Text-based vs. Object-based Material 1 2 3 Chair: Rebecca Grube Igino Teolis* , Ellen B. Peffley , Roman Taraban , David B. Wester4, Cynthia McKenney5 3:15 pm–4 pm ORAL SESSION 8 555A 1Plant and Soil Science, Texas Tech University, Box 42122, Lubbock, Texas, 79409, 2Dept. of Plant and Soil Science, Texas Tech University, Teaching Methods Box 42122, Lubbock, Texas, 79409, 3Dept. of Psychology, Texas Tech Moderator: Alice Le Duc University, Box 42051, Lubbock, Texas, 79409, 4Dept. of Range, Wild- life, and Fisheries Management, Texas Tech University, Box 42125, 3:15 Demystifying the ICNCP - Cultivated Plant Code1995 Edi- Lubbock, Texas, 79409, 5Dept. of Plant and Soil Science, Texas Tech tion and Upcoming 2003–04 Edition Univ. and Texas A&M Univ., 17360 Coit Rd., Dallas, Texas, 75252 Alice Le Duc* The purpose of this study was to examine the relative effectiveness Sarah P. Duke Gardens, Duke University, Box 90341, or, 426 Anderson of three teaching methods in delivering material that was predominantly Street, Durham, NC., 27708 text information (i.e., text-based) or material that was predominantly In the latest editions the International Code of Nomenclature for visual information (i.e., object-based). The text-based lesson was on Cultivated Plants (ICNCP) has undergone some dramatic changes. photosynthesis and the object-based lesson was on tropical plant iden- The intent was to provide a simple system for an increasingly diverse tification. Each participant in the study was instructed on one of these and complex assemblage of plants. The 1995 edition has not satisfac- two topics and received the instruction by one of three delivery methods: torily resolved all the problems but with the revisions in the upcoming 1) independent learning using a text handout, 2) traditional learning 2003–04 edition there is a hope for international harmony. To many of involving a summary lecture and a text handout, and 3) independent the users and givers of plant names the code is a maze they would rather web-based learning involving material all on the computer, resulting not navigate. However without an understanding of and adherence to in a 2 ×3 factorial design. Participants receiving the tropical plant the Code the difficulties we face today will only become magnified. identification lesson through independent web-based learning viewed A simplified guide for horticulturists, nurserymen, gardeners and stu- photographs of the plants, while those receiving the lesson through dents is currently being developed by the members of the Horticultural independent learning or traditional learning had access to live plant Taxonomy Group (HORTEX). Key components are descriptions of the specimens in the University greenhouse. Each participant had up to one categories governed by the Cultivated Plant Code, commercial names, hour to study the material. The following day, each participant was asked expanding use of Plant Breeders· Rights (PBR) and how to publish a to complete a concept mapping exercise (in which the participant linked new cultivar name. One of the most important additions to the revised the concepts that were learned from the lesson), an exam consisting of Code is the establishment of a designated Standard with an accompa- 20 multiple-choice questions, and a survey that included an assessment nying portfolio. In this era of intensive plant breeding and expanded of the participant·s learning styles. The exam scores and the number of marketing, international trade and high consumer interest in plants, relevant concepts from the concept mapping exercise were statistically improved communication between the scientific and the horticultural analyzed to test for significant differences between the delivery meth- communities is essential to co-existence. It is imperative that we have a ods and to test for an interaction between delivery method and topic. unified system of nomenclature that everyone understands and adheres to. Analyses of the survey results were done to test for differences in the perceptions of the participants toward the three delivery methods and to examine for correlations between learning styles and perceptions, 3:30 Web-based Pre-visits are Effective for Educating Elementary exam performance, and concept mapping performance for each of the Students Visiting A Public Garden delivery methods. Preliminary results indicate that participants in the Jon Pieper*, Cynthia Haynes independent web-based learning treatment had the highest scores for Horticulture, Iowa State University, 106 Hort. Hall, Ames, IA, 50011 the text-based lesson while participants in the traditional learning treat- ment had the highest scores for the object-based lesson. Participants Creating effective learning experiences with today·s stretched educational resources has made educators evaluate the need for field generally performed well on the exams (mean score above 80%) but trips. Pre-visit activities in the classroom prior to a field trip experi- had difficulty recalling the concepts they learned when they did the ence increase attention and therefore learning of students. Tradition- concept mapping exercise. ally, speakers from the garden or the teachers would lecture about

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3:30 pm–4:45 pm ORAL SESSION 9 552B 22%, 28%, and 41%, respectively. Planting dates were between October 28–November 10, 1997, April 30–May 7, 1998, October 23–28, 1998, Nursery Crops—Environment and Growth Management and May 1–10, 1999. Plants were covered with plastic and straw from Moderator: Mary Meyer the second week in November until the second week in April. Winter fi 3:30 The Effects of Heat on Photosynthesis in Acer rubrum survival was evaluated 6 weeks after uncovering and for nished dates every two weeks thereafter. Sporobolus heterolepis and Miscanthus 1 2 David Weston* , William L. Bauerle sinensis ‘Variegatus· had significantly lower over-wintering survival 1Horticulture, Clemson University, P&A Building, Room 136, Perimeter than the other selections. Schizachyrium scoparium; Calamagrostis Rd., Clemson, SC, 29634, 2Horticulutre, Clemson, P&A Building, xacutifl ora ‘Karl Foerster·; and Miscanthus ‘Purpurascens·performed Room 136, Perimeter Rd., Clemson, SC, 29634 almost equally well across media porosities. Sporobolus heterolepis The effects of heat on photosynthesis were investigated in Acer had significantly lower winter survival in low than in high porosity rubrum‘Florida Flame·andAcer rubrum‘Northwood·, which are known media. Overall, the low porosity media resulted in lower root dry to differ in heat tolerance. The photosynthetic temperature optima under weights and smaller crown diameters. Containers influenced growth control conditions, for Florida Flame and Northwood was 28–33 °C as a function of volume with 6.2 L containers having the highest values and 25–30 °C, respectively. When plants were acclimated to elevated for all growth parameters. temperatures, 10 °C above control, for sixteen days the photosynthetic temperature optima increased by 3 °C for both cultivars. Leaf absorbtance 4:15 Effect of Container Size and Cupric Hydroxide Application did not change in the photosynthetically active radiation (PAR) region on Growth of Pawpaw (Asimina triloba) Seedlings between cultivars or temperature regime. Under high temperature (42 1 2 °C), both basal fluorescence (Fo) and non-photochemical quenching Kirk Pomper* , Snake Jones (qN) fluorescence parameters increased, indicating photosystem II 1Community Research Service, Kentucky State University, 129 Atwood (PSII) acceptor side limitation. Under similar temperatures alternative Research Facility, Frankfort, Kentucky, 40601, 2Community Research electron transport increased for both cultivars. However, Florida Flame Service, Kentucky State University, Atwood Research Facility, Frank- exhibited less thermoinhibition and less PSII acceptor side limitation fort, Kentucky, 40601 compared to Northwood. Rubisco activity in both cultivars decreased The North American pawpaw [Asimina triloba (L.) Dunal] has in response to heat and the rate of decrease was related to cultivar and potential for use as a new tree fruit crop or in landscapes. Pawpaw has temperature acclimation. Our research indicates that photosynthetic a strong taproot that complicates container production. A randomized decline of red maple to moderate heat is in part due to Rubisco activity, block greenhouse experiment was conducted to examine the influence

and we propose that the regulation of Rubisco is essential in providing of container size and application method of Cu(OH)2 paint (SpinOut) plant tolerance and acclimation mechanisms. to the interior of containers on root and shoot development. Seeds were sown in treated and untreated Rootrainers or Treepots with ProMix-BX 3:45 Effects of Pot Color on Soil Temperature and Root growing substrate. Rootrainer (0.7 L/cell) treatments included: 1) paint Development on Rhododendron obtusum Kurume Azalea applied by brush, 2) paint diluted with water (3:1) applied by brush, 3) containers dipped in paint, and 4) no paint applied as a control. ‘Hot Shot· Treepots (7.6 L) were either dipped in Cu(OH)2 paint to coat the interior Wayne J. McLaurin* or were untreated. There were 30 replicate seedlings per treatment. At Horticulture Department, University of Georgia, Athens, GA, 30602 18 weeks after sowing, seedlings in Rootrainers set terminal buds and The root zone temperature is critical for proper plant growth. One were destructively harvested. Seedling height was reduced by 25% of the main factors affecting root growth is the amount of heat units in dipped Rootrainers compared to the control. Seedling total shoot, accumulated within the pot. Color affects heat absorption. The objective total root, and lateral root dry weights were about 30% lower in dipped of using different colored pots is to evaluate the effect of pot color on and regular paint Rootrainers than for control seedlings. During early plant growth and development. The following colored pots were used development, seedlings in treated Treepots were shorter than those in the study: purple, burnt orange, maize, white, copper, terra cotta, in untreated Treepots. However, by harvest (26 weeks) seedlings in green,fiber, mauve, burgundy, t-green (t-slightly thinner plastic), black, treated Treepots were 20% taller than those in the untreated control. At t-black, t-rust. Fiber pots produced significantly more plant height than 26 weeks, seedling total shoot, total root, and lateral root dry weights the other pot colors. The rust and green pots produced significantly lower were about 35% greater in treated containers than the control. Treat- ment of 7.6 L Treepots with Cu(OH) greatly improved seedling root heights than all other color pots. White pots produced significantly more 2 plant growth diameter that the succeeding pots while at the same time biomass development. the rust and green pots produced significantly lower heights than all other pot colors. Also,the white pots had significantly more dry weight 4:30 Identification and Management of Inula britannica in production than the other pot colors. Michigan Nurseries Robert Richardson*1, Bernard Zandstra2 4:00 The Effects of Media Aeration Porosity and Container Size 1Horticulture, Michigan State University, A432 PSSB, East Lansing, on Over-wintering and Growth of Ornamental Grasses MI, 48824, 2Horticulture, Michigan State University, PSSB, East Mary Hockenberry Meyer*1, Bruce Cunliffe2 Lansing, 48824 1Horticultural Science, University of Minnesota, 3675 Arboretum Inula britannica is an invasive, perennial member of the Asteraceae Drive, Chanhassen, MN, 55317, 2Glacial Stone Nursery, Wisconsin, family that has recently been introduced into several Michigan nurs- N5500 County Rd D, Leoplis, WI, 54948 eries through contaminated nursery stock. This weed has distinctive fl Five ornamental grasses {little bluestem [Schizachyrium scoparium yellow disc and ray owers, pubescent stems and leaves, and leaves (Michx.) Nash], prairie dropseed [Sporobolus heterolepis (A. Gray) A. usually have a slightly clasping attachment to the stem with no petiole. Gray], feather reedgrass [Calamagrostis xacutiflora(Schrad.) DC. ‘Karl Flowers can produce large quantities of wind-disseminated seed, and Foerster·],flamegrass (MiscanthusAnderss. ‘Purpurascens·), and varie- roots form dense colonies by vegetative reproduction. Current control gated Japanese silvergrass (Miscanthus sinensisAnderss. ‘Variegatus·} methods involve complete crop destruction to eradicate the weed. Field were propagated by transplanting plugs or field divisions into either and greenhouse studies were conducted in 2002 and 2003 to evaluate fi 480-mL (4-inch round), 2.7-L (#1), or 6.2-L (#2) nursery containers potential herbicidal controls. In Fall 2002 eld studies, I. britannica containing media with ratios (v/v) of 0:1, 1:1, 2:1, 3:1, 1:0 rice hulls to control was 95% or greater with 2,4-D, dicamba, clopyralid, clopyralid sand, resulting in aeration porosities in 2.7-L containers of 5%, 12%, plus triclopyr, and glufosinate at 11 weeks after treatment. In greenhouse

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studies, control with 2,4-D, dicamba, dicamba plus diflufenzopyr, clopy- Rd., Aurora, OR, 97002 FRIDAY pm ralid, clopyralid plus MCPA, clopyralid plus triclopyr, and glufosinate CPPU (N-(2-chloro-4-pyridinyl)-N-phenyl urea) was applied was at least 95% at 4 weeks after treatment. Glyphosate, fluroxypyr, 3 weeks after petal fall at a concentration of 10 mg/L on highbush fl umioxazin, halosulfuron, and imazapic did not consistently control blueberry ‘Elliott·. Berry weight, size, Brix, firmness, and color were the weed in field or greenhouse studies, although some suppression determined against untreated controls at each harvest. Three harvests was observed. were carried out by commercial pickers. CPPU treatment significantly increased berry weight and size in all three harvests. The increase in 3:30 pm–5:00 pm ORAL SESSION 10 557 hundred-berry weight from the first to the third harvest was 5%, 18%, and 25%. CPPU did not affect Brix and color of mature blueberry Plant Growth Regulators and Genetics fruit. Berry firmness at the first two harvests was not affected by CPPU Moderator: Brent Black treatment. However, the berries treated with CPPU were softer at the 3:30 Fragaria virginiana Tolerates Tarnished Plant Bugs third harvest than those untreated controls. Overall, CPPU application fi 1 1 2 delayed harvest by two weeks, which is very signi cant to the late- Adam Dale* , Dragan Galic , Rebecca Hallett season fresh blueberry market. 1Plant Agriculture, University of Guelph, 1283 Blueline Road, Box 587, Simcoe, Ontario, N3Y 4N5, Canada, 2Environmental Biology, Univer- sity of Guelph, Bovey Building, Guelph, Ontario, N1G 2W1, Canada 4:15 Chemical Bloom Thinning Hybrid Wine Grapes Tarnished plant bugs (Lygus lineolaris) are one of the two major D.C. Ferree*, D.M. Scurlock, J.C. Schmid pests of June-bearing strawberries, and the major pest of day-neutral The Ohio State University, Wooster, OH 44691 strawberries in Ontario. In order to develop cultivars that are tolerant Three French-American hybrid grape cultivars with a tendency to to the pest, sources of tolerance or resistance need to be identified. For overcrop were sprayed with three chemicals at 50-75% open bloom to two years, damage to the fruit by tarnished plant bug was recorded in evaluate thinning potential. Generally as the rate of Endothall increased, a planting which contained 12 single-plant replicates of 200 cultivars, berries per cluster and yield decreased. Ammonium thiosulfate caused advanced selections, genotypes of Fragaria virginiana, and hybrids excessive leaf injury and resulted in over-thinning when applied under between F. virginiana, and F. chiloensis and F. ×ananassa. The F. high temperatures. Endothall and Wilthin resulted in visible necrosis virginiana genotypes were, as a group, very tolerant of tarnished plant on both leaves and clusters following application but subsequent bug, the cultivars and advanced selections, as a group, were much less growth was unaffected. Generally, Endothall (1.9 mL/L) and Wilthin tolerant. The hybrids segregated into those that were tolerant and those had no effect on cluster number, but reduced berry number per cluster that were not. The cultivars and selections varied in their reaction from and cluster weight and resulted in an increase in juice soluble solids those that more tolerant to those that were very intolerant; none were as similar to hand-thinned vines. Hand thinning at bloom reduced cluster tolerant as the most tolerant F. virginiana genotypes. Possible reasons number per vine and increased berries per cluster and cluster weight for this variation are discussed. on all three cultivars with the greatest effect on ‘Vidal blanc·. Bloom thinning sprays of Endothall and Wilthin show potential to achieve 3:45 Fruit Nitrogen Content of Eleven Strawberry Genotypes similar results to hand-thinning by reducing yield and increasing juice Grown in Advanced Matted Row Culture quality on ‘Seyval blanc·, ‘Chambourcin·and ‘Vidal blanc·. However, the reduction in crop is achieved by reducing berries per cluster by the 1 2 1 Brent L. Black* , Stan C. Hokanson , Kim S. Lewers chemicals and not whole cluster removal. 1Fruit Laboratory, USDA-ARS, Building 010A, BARC-W, 10300 Balti- more Ave., Beltsville, MD, 20705, 2Horticulture Science Department, 4:30 Interaction Between the Pathogen and Host Plants during University of Minnesota, Alderman Hall, St. Paul, MN, 55108 the Pierce·s Disease Development of Grapevines Information on nitrogen (N) removal during harvest is necessary for developing fertility programs and for nutrient management planning. J. Lu*, X. Xu, Z. Ren, H. Yun, X. Liu Five strawberry cultivars and six numbered selections were grown in Center for Viticulture, Florida A&M University, 6505 Mahan Drive, advanced matted row culture (AMR) and compared for harvest removal Tallahassee, FL, 32317 of N over two seasons. The cultivars Allstar, Earliglow, Northeaster, Pierce s disease (PD) is a limited factor to production of non-native Ovation, and Latestar, and the numbered selections B51, B683, B781, grapes in the southeastern United States. The disease has recently B793, and B817 were established in replicated AMR plots in both 1999 received national and international concerns due to its outbreak in and 2000. During establishment, plots were fertilized with 130 kg N per California. Pierce's disease is caused by a bacterial pathogen known hectare. During the first fruiting season, ripe fruit was harvested twice as Xylella fastidiosa (XF) which is transmitted by leaf hoppers when weekly to determine total yield. Sub-samples were collected weekly they feed on grapevines. It has generally been believed that clogging and stored for subsequent N analysis. The fruit sample corresponding the xylem vessels by XF results in the typical PD symptoms: marginal to date of peak harvest was dried and total N determined by Dumas necrosis, uneven lignifications of annual canes, abscissions occurring combustion. There were significant differences in harvest removal of between leaf blades and petioles, and dead shoots. However, there N among genotypes. N removal values for numbered selections ranged are many unexplained phenomenon during the course of the disease from 14.4 to 20.1 kg N per hectare for B51 and B793, respectively. development, and the real causes of PD maybe more complicated than For cultivars, N removal ranged from 15.2 to 21.6 kg N per hectare water deficiency. In order to better understand the mechanism of the for ‘Ovation·and ‘Earliglow·, respectively. The amount of N removed disease development and host plant resistance to PD infection, we at harvest was largely determined by yield, however there were also have been investigating the pathogenesis of XF, interactions between significant genotype differences in fruit N content, ranging from 0.67 to XF and grapevine, variations and changes of plant growth regulators 1.00 mg N per gram fresh weight for B817 and ‘Earliglow·, respectively. among PD resistant and susceptible grapes. It appeared that the PD The harvest N removal rates presented here represent 11.1% to 16.6% symptom development associated with physiological and biochemical of fertilizer N applied in the establishment year. changes of grapevines. For example, both ABA and SA levels increased during the course of PD development. In the mean time, PD infected 4:00 CPPU Application Delayed Maturity of ‘Elliott·Highbush leaves showed various abnormalities with symptoms similar to mineral fi Blueberry in Oregon nutrient imbalances such as phosphorous (P) de ciency and magnesium (Mg), manganese (Mn) and iron (Fe) toxicities. In addition, the PD Wei Qiang Yang* infected leaves and petioles showed significantly lower levels of K Horticulture, North Willamette Res & Ext Center, 15210 NE Miley and higher levels of Fe, Cu, and Zn than those non-infected ones.

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In a separate study, when culture filtrates from X. fastidiosa were one or more cycles of crosses (intra- or interspecific hybridization), and placed on wounded leaf segment, the susceptible cultivars showed select genotypes exhibiting commercially acceptable traits. Polyploidy severe symptoms while no or very mild symptoms were found on PD has been used to restore fertility in interspecific hybrids (Zinnia) and to resistant cultivars. Two toxic compounds were also isolated from the increaseflower size, diversity of flower color, and stem strength in Easter XF culture filtrate. This result indicated that PD symptom development cactus (Hatiora ×graeseri) and Thanksgiving cactus (Schlumbergera maybe associated in part with a toxic effect from X. fastidiosa. Our truncata). Research on the reproductive biology, cytology, and genetic studies revealed that the PD development involves a series of complex diversity within germplasm collections has been helpful for clarifying interactions between the XF pathogen and the host plant, and many genetic relationships between different accessions and selecting parents physiological and biochemical changes occured in the host plants for crosses. Recent releases from my breeding program include some during PD development. seed-propagated crops (Alternanthera dentata,Pennisetum alopecuroi- des) and vegetatively-propagated crops (Boltonia latisquama,Hatiora, 4:45 Somatic Embryogenic Line Induction and Maintenance Schlumbergera). Cooperation with commercial growers and/or seed companies is advantageous for selecting, protecting, and marketing of Grapevines new cultivars. Xia Xu*, Jiang Lu fi Center for Viticulture, Florida A&M University, 6505 Mahan Drive, Rede ning Bedding Plant Petunias Tallahassee, FL, 32317 Robert J. Griesbach*, U.S. National Arboretum USDA-ARS: Somatic embryogenesis is a rapid propagation method and an The Elusive Blue Cineraria: A Breeding Case History At important tool for genetic transformation and somatic hybridization. Longwood Gardens” An experiment was initiated to induce somatic embryogenic lines from grapevines. Embryogenic lines were obtained from immature James F. Harbage*, Longwood Gardens: ovules extracted from berries of muscadine grape cultivars ‘Summit· Breeding New Chilean Bulb Species and ‘Tara·as well as bunch grape cultivars ‘Autumn Royal·, ‘Crimson Mark Bridgen* Seedless·, and ‘Fantasy Seedless· when cultured on three different media with or without plant growth regulators (PGR). The induction Cornell Univ., Long Island Horticultural Research & Extension Center of embryogenic lines was highly genotype-dependent and thus far Floriculture Breeding at the University of Florida·s Gulf was confined to these cultivars. However, the embryogenic lines from Coast Research and Education Center: Past, Present ‘Summit· and ‘Tara· were stable maintained on Murashige & Turcker and Future (MT) medium supplemented with 1 µM 2, 4-D and 1 µM NAA while the embryogenic lines from ‘Autumn Royal·, ‘Crimson Seedless·, and Zhanao Deng and Brent K. Harbaugh ‘Fantasy Seedless· grew better on CP medium supplemented with 0.2 University of Florida, IFAS, Gulf Coast Research and Education µM BAP and 1µM NOA. Plant regeneration was successfully achieved Center, 5007 60th Street East, Bradenton, FL 34203 from those embryogenic lines when transfer them to the Woody Plant Floriculture breeding began at the University of Florida·s Gulf Coast (WP) medium supplemented with 1 µM BA. Research and Education Center in the early 1950·s. Our program is part of the statewide ornamental breeding effort of the UF·s Environmental 3:30 pm–5:30 pm WORKSHOP 6 552A Horticulture Department, and it has remained very active, dynamic and Ornamental Plant Breeding in the East productive for the last 50 years. More than 40 new gladiolus, orchid, gypsophila, caladium, lisianthus, and ornamental tomato cultivars have Moderator: Neil O. Anderson been released. Breeding efforts were initially focused on cut flowers and Sponsor: Ornamental Plant Breeding Working Group (OPB) have gradually shifted toward flowering potted plants and landscape Objective: The objective of this workshop is to provide a forum plants. Disease resistance and heat tolerance, as well as improved fl for herbaceous and woody plant breeders to present historical ower or foliage color, quality and production, were and remain to be the top breeding objectives, so that released varieties are well adapted summaries of their crop-specific breeding programs, as well as to commercial production and/or garden performance in the Southern providing future directions. United States. Cross hybridization and inbreeding have been the main Summary:The Ornamental Plant Breeding Working Group is spon- approaches used in the past. Currently, several new technologies are soring a workshop on “Ornamental plant breeding in the east”. This being adapted and applied to improve breeding efficiency or to overcome workshop includes several plant breeders, from academic, private certain barriers. Caladium, lisianthus, and gerbera are crops currently gardens, and USDA breeding programs in the eastern United States, in our breeding program. who will share historical perspectives, past breeding/genetic ac- Building on Success: 45 Years of Crapemyrtle Breeding complishments, and future breeding objectives. Talks will include at the U.S. National Arboretum herbaceous and woody annual/perennial crops, given by seasoned Margaret Pooler* breeders and recent hires. USDA/ARS/U.S. National Arboretum, 3501 New York Ave., NE, Interspecific Hybridization Among the Large-bracted Washington, DC 20002 Dogwoods and Holly Species The crapemyrtle (Lagerstroemia) is a popular shrub or tree with Elwin Orton*, Rutgers University hundreds of named cultivars that offer the grower and gardener diverse combinations of flower color, growth habit, and bark characteristics. Breeding of Floricultural Crops at the University of Although originally from Asia, the crapemyrtle or “lilac of the south” Massachusetts has become a mainstay in southern U.S. gardens and represents a Thomas H. Boyle* significant source of income for both wholesale and retail nursery growers. Some of the greatest strides and most lasting contributions Dept. of Plant and Soil Sciences, Univ. of Massachusetts, Amherst, to crapemyrtle improvement came from the late Donald Egolf of the MA 01003 USDA/ARS/U.S. National Arboretum in Washington, D.C. As one The primary objective of my breeding program is the develop- prominent crapemyrtle wholesale grower said, “Our story of crape- fl ment of new cultivars of bedding plants or owering potted plants for myrtle development would be very short were it not for Dr. Donald commercial production. My general approach has been to obtain and R. Egolf.” By incorporating germplasm from L. fauriei into his breed- evaluate germplasm of promising species plus related taxa, perform

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ing program, he was able to develop cultivars that were resistant to benefit sharing and increased partnerships with host countries. Some FRIDAY pm powdery mildew. Since the release of ‘Natchez· and ‘Muskogee· in examples will be offered that illustrate the contributions of benefit shar- 1978, 20 additional interspecific hybrid cultivars have been released ing and innovative methodologies toward improving the effectiveness from the U.S. National Arboretum, many of which have set the of the NPGS's Plant Exploration Program. standard for disease resistance in the nursery industry. In addition to breeding for disease resistance, the current breeding objectives The Sino-American Botanical Expedition of 1980: A for crapemyrtle at the Arboretum focus on the development of novel Retrospective Analysis of Success flower colors, early bloom, and compact or miniature plant habit. The Michael S. Dosmann*1, Peter Del Tredici1,2 history and future of crapemyrtle breeding at the National Arboretum 1Department of Horticulture, Cornell University, Ithaca, NY 14850; will be discussed. 2The Arnold Arboretum of Harvard University, Jamaica Plain, MA From Cape Town to Commercialization: The History of 02130, Department of Horticulture, Cornell University Pelargonium Domestication The 1980 Sino-American Botanical Expedition (SABE) to the Shen- nongjia Forest District, Hubei Province, China was the first botanical Richard Craig*, Pennsylvania State University collecting trip by American scientists to that country since 1949. This collaborative venture with Chinese botanists yielded 2085 herbarium 3:30 pm–5:00 pm WORKSHOP 7 555B and 621 germplasm collections from the species-rich region. A few Germplasm Acquisition from Conception to Products collections (e.g., Heptacodium miconioides, Magnolia zenii, and Sor- bus yuana) have been successfully introduced as ornamentals, while Moderator: Mark P. Widrlechner others are under further evaluation. This analysis tracked the fate of Sponsor: Genetics and Germplasm Working Group (GG) the SABE germplasm 22 years after its introduction to North America and represents one of the few case studies of its kind. Two hundred Objective: The workshop will present information on important and fifty-eight of the original germplasm collections still survive and aspects of germplasm acquisition ranging from planning and finan- are in cultivation in at least one of 18 botanical institutions. Yet 115 of cial support for explorations to the successful introduction of new these (45%) are represented by a single accession growing in a single varieties and valuable genes from recent collections. location, which suggests that the plant introduction process is more tenuous than is generally assumed. The scientific value of documented Summary:This workshop will examine important aspects of interna- wild germplasm warrants that careful measures are in place to ensure tional germplasm acquisition, beginning with an overview of the ex- that significant collections do not vanish. This case study outlines steps plorations and exchanges supported by the US National Plant Germ- that can be taken throughout the introduction process (from propagation plasm System and including analyses of the success of germplasm to distribution and follow-up) to prevent any such loss. In particular, propagation and introduction from the first major Chinese exploration the role of data sharing among institutions is highlighted as a means of after the re-establishment of diplomatic relations between the United identifying collection uniqueness, and assessing environmental adapt- States and the People·s Republic of China and reports from two ability and invasiveness. researchers who collected both wild and improved germplasm in sup- Acquiring Important Prunus Germplasm from Central port of breeding efforts, examining various aspects of the exploration and Eastern Europe process and the discovery of valuable germplasm through evaluation. Amy Iezzoni* An Overview of the U.S. National Plant Germplasm Department of Horticulture, East Lansing, MI 48824 System·s Exploration Program The sour cherry industry in the United States is a monoculture Karen Williams* of a 400-year-old variety from France named ‘Montmorency·. To USDA-ARS, National Germplasm Resources Lab., Beltsville, MD provide a solid germplasm base for a domestic sour cherry breeding The Plant Exploration Program was established by USDA in 1898, program to develop alternatives to ‘Montmorency·, cherry germplasm several decades before the US National Plant Germplasm System was systematically collected over a ~15-year period from its ancestral (NPGS) itself, and continues to support international and domestic home in Central and Eastern Europe and introduced to the U.S. The plant explorations for germplasm acquisition. These explorations are strategy of germplasm collection utilizing pollen, seed and budwood designed to fill collection gaps identified by the 40 Crop Germplasm importation of a highly quarantined species will be discussed. Valuable Committees that counsel the NPGS. Approximately 15 explorations are germplasm resulting from this effort will be highlighted, including a conducted annually under the auspices of this program. Although plant few examples of commercial success. Finally, the “recycling” of this fi explorations to remote areas are often still the only means of acquiring immense germplasm collection to search for dwar ng precocious unique new germplasm, the focus and methods applied by modern rootstocks for sweet cherry will also be detailed. plant explorers have changed significantly in recent years in response Realizing Value from Central Asian Allium Collections to evolving germplasm needs and the new opportunities presented by Philipp Simon* recent technological advances. Modern explorations are characterized by the targeting of specific taxa and traits. Wild species in the secondary USDA, ARS Vegetable Crops Research Unit, 1575 Linden Dr., Horti- or tertiary genepools of major crops are frequently emphasized, largely culture Department, University of Wisconsin, Madison, WI 53706 resulting from their increased use in crop improvement having been Central Asia is the center of origin for many Allium species and facilitated by molecular genetics. Other wild species are targeted for a rich genetic source of wild relatives of onion, garlic, and leek. For their potential as new crops. New exploration techniques and tools, this reason, germplasm curators of cultivated Allium have targeted the including geographical information systems and improved methods acquisition of seed and bulb samples from this region, and several plant of data collection, are being applied to locate, document, and assess expeditions from Asia, Europe, and North America have collected Allium plant genetic diversity. During the past decade, legal obstacles faced germplasm in Central Asia. The value of germplasm collections can be by the Program have increased due to restrictive laws implemented in measured by the addition of accessions to the collection, by the number germplasm "donor" countries that exercise their national sovereignty of requests for those accessions, by research on the collection, and by over genetic resources, replacing the free and open access to genetic the utilization of those accessions to improve these crops for modern resources that prevailed prior to the ratification of the Convention on agriculture. By any of these measures, Central Asian Allium collections Biological Diversity in 1993. The NPGS has responded to these regula- have been valuable. Challenges and successes in collecting, maintaining, tory challenges with a flexible approach that includes non-monetary evaluating, and utilizing these collections will be discussed.

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3:30 pm–5:30 pm COMMITTEE MEETING 554B 4:00 pm–5:00 pm ORAL SESSION 11 556A Reseach Advisory Council Pomology—Thinning Chair: Mikal Saltveit Moderator: Esmaeil Fallahi fl 3:30 pm–5:30 pm COMMITTEE MEETING 550B 4:00 In uence of Organic Blossom Thinners on Fruit Set and Quality in Apples, Peaches, and Plum Extension Advisory Council Esmaeil Fallahi*1, Curt R. Rom2, Bahar Fallahi1 Chair: William J. Lamont, Jr. 1Parma Research and Extension Center, University of Idaho, 29603 U of I Lane, Parma, Idaho, 83660, 2Dept. of Horticulture, Univ. of 3:30 pm–4:30 pm STUDENT ACTIVITY 551B Arkansas, 316 Plant Science Building, Fayetteville, AK 72701-1201 ACB Oral Competition Lime sulfur and Natural Cal at different rates were applied for Moderator: Jill Montgomery, ACB President blossom thinning in apples, peaches, and plum in 2001 and 2002. Lime sulfur at 5%, either at a single or double application during (338) Effect of Uniconazole and Ancymidol on Growth of 80% bloom, reduced fruit set in ‘Gala·apple in 2001, but not in 2002. Hydrangea quercifolia Natural Cal at 6% effectively reduced ‘Gala· apple fruit set in 2001. Robert O. Brown*1, Janet C. Cole1 In 2001, application of lime sulfur at 6% effectively reduced fruit 1Horticulture and Landscape Architecture, Oklahoma State University, set in peaches and ‘Empress· plum. However, a single application 360 Ag Hall, Stillwater, OK, 74078-6027 of lime sulfur at 6% was not effective on ‘Red Globe· or ‘Elberta· peach blossom thinning in 2002. Double application of lime sulfur Hydrangea quercifolia plants were treated with a uniconazole or a single application of Natural Cal had a moderate effect on peach medium drench at 0, 1, 2, or 4 mg a.i./L or with a uniconazole foliar thinning in 2002. Temperature and time of application had a major application of 0, 12.5, 25, or 50 mg a.i./L per container. Separate plants impact on the effectiveness of blossom thinners. were treated with an ancymidol medium drench of 0, 1, 2, or 4 mg a.i./L or an ancymidol foliar application of 0, 25, 50, or 100 mg a.i./L. Heights and widths, and root dry weights of plants receiving uniconazole 4:15 Crop Load Management in Washington via Chemical as a soil drench decreased as drench rate increased. Heights, widths Thinning and root and shoot dry weights of plants receiving a foliar treatment Jim McFerson* of uniconazole also decreased as the treatment rate increased. Plant Horticulture, Washington Tree Fruit Research Commission, 1719 heights decreased as ancymidol soil drench rate increased six weeks Springwater Ave, Wenatchee, WA, 98801 after treatment, but no differences were apparent at any time in other parameters measured. Foliar-applied ancymidol did not affect plant Apple growers have limited options to chemically thin fruits in their crop heights or widths at any time during the experiment or shoot or root dry load management programs to encourage annual bearing and enhance weights at harvest. Chlorophyll content of leaves from plants receiving harvest fruit size and quality. In the U.S.A., registered materials are each treatment was determined. inconsistent and/or costly. Post bloom thinners are routinely employed in conventional orchards, but expensive green fruitlet hand thinning is usually employed. We have developed cost-effective chemical thinning (827) Chemical Height Control of Containerized Kosteletzkya programs with application windows from pre- to post-bloom, based on virginica over 100 replicated trials on 14 cultivars in commercial and organic Kimberly Hilgers*, Cynthia Haynes, William R. Graves orchards throughout Washington. Response variables included: 1) initial Horticulture, Iowa State Univ., 106 Horticulture Hall, Ames, IA 50011 bloom clusters per sampling unit (branch, tree, trellis section) and cross sectional area; 2) post-treatment number of clusters with zero (blank), Virginia Mallow [Kosteletzkya virginica (L.) C. Presl ex A. Gray] is one, two, three, or more than four fruitlets; 3) time required to hand a native perennial with potential as a landscape ornamental. Production thin sampling units; 4) return bloom on sampling units (measured in of this species in containers typically results in plants that are too tall subsequent season): and, 5) harvest fruit quality parameters (size, L/D and lanky for successful marketing. To aid and encourage commercial ratio, soluble solids, titratable acids, starch index, firmness, fruit finish). production of compact K. virginica, five chemical plant growth regula- The most effective treatments were tank mixes of lime sulfur (calcium tors were evaluated at three rates for effects on plant height, internode polysulfide) at 2% to 3% vol:vol with various fish, vegetable, or petro- length, and lateral branching. A-Rest (15, 25, and 50 ppm), Atrimmec leum oils at 0.5% to 2.5% vol:vol. Caustics like ammonium thiosulfate, (500, 1000, and 1500 ppm), Cycocel (750, 1000, and 1500 ppm), and lime sulfur, or calcium chloride/magnesium chloride mixtures at 2% to a Cycocel/B-Nine mix (1000/2500, 1000/5000, and1500/5000 ppm) 8% vol:vol were less consistent. Our best treatments routinely reduce were each applied once to seedlings, while Bonzi (10, 20, and 60 ppm) initial crop load >50%, with cluster composition significantly skewed was applied twice as recommended on the label. Ten replicates of each toward blanks, singles, and doubles. Hand thinning time was reduced rate were evaluated weekly and compared to a control for eight weeks. from 25% to 50%. Return bloom was significantly enhanced vs. control Cycocel and Cycocel/B-Nine reduced the height of K. virginica by 62% treatments. Harvest fruit size was regularly increased. Results on pears and 64%, respectively, and Bonzi-treated plants were 23% shorter than and cherries are promising controls. Averaged across chemicals, low and moderate application rates showed similarly strong effects on height reduction; relatively small additional reductions resulted from use of the highest rates. Cycocel 4:30 Organic Post-bloom Apple Thinning with Fish Oil and and Cycocel/B-nine treatments led to 86% more lateral branches than Lime Sulfur were present on controls, and Bonzi resulted 60% more branching. A- Heidi Noordijk*1, James Schupp2 Rest and Atrimmec did not affect plant height nor increase the number 1Horticultural Sciences, Cornell Univeristy, Hudson Valley Lab, PO Box of branches, and no difference in internode length was found between 727, Highland, NY, 12528, 2Horticultural Sciences, Cornell University, any treatments with these chemicals. In addition to the height control Hudson Valley Lab, PO Box 727, Highland, NY, 12528 and increased branching found on K. virginica treated with Cycocel and Cycocel/B-Nine, plants appeared darker green and to have thicker A study was conducted in New York·s Hudson Valley to evaluate leaves. We conclude that the marketability of containerized K. virginica timing and frequency of an organically acceptable post-bloom thin- can be enhanced most effectively by a one-time application of Cycocel ner for reducing fruit set and increasing fruit size and fruit quality at 750-1000 ppm. in apple. Mature ‘McIntosh·/M.27 and ‘Empire·/M.27 apple (Malus ×domestica Borkh.) trees were thinned with 2% Crocker·s Fish Oil

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tank mixed with 2.5% liquid lime sulfur (FOLS). Applications were economical advantages to the farmers. Samsun province of Turkey has a FRIDAY pm targeted for seven days after petal fall (DAPF), 14 DAPF, 21 DAPF, great agricultural potential because of it has two great and fertile plains, and as double applications at seven DAPF plus 14 DAPF, and 14 Bafra and Çarsamba. Port and airport in the province are important ex- DAPF plus 21 DAPF. All treatments were compared with an unthinned portation gates. Exportation of these vegetables is possible through these control. Fruit set was reduced in McIntosh for all treatments, double gates. Using of broccoli in the frozen food industry will gain chances applications reduced fruit set more than single applications. McIn- to improve frozen food industry in the region. ln addition, if tourism is tosh fruit size was increased in all treatments, double applications developed in the region very fast and beauty of the region is introduced and a single application seven DAPF resulted in the largest fruit. All to the tourists, growing area of these vegetables will increase day by day. FOLS treatments increased fruit size in Empire. Increased levels of leaf phytotoxicity and fruit russet were found in all treatments. Leaf photosynthesis was reduced in Empire for all treatments, with double 4:15 Early Muskmelon Production in Southern Illinois applications having the longest suppression time. Results suggest that S. Alan Walters* FOLS thins fruits by inhibiting photosynthesis and decreasing assimi- Plant, Soil, and Gen. Agr., Southern Illinois University, 1205 Lincoln lates to developing fruits. FOLS has potential as a viable post-bloom Dr., Ag. Bldg. Rm. 176, Carbondale, Illinois, 62901-4415 organic thinner for apple. Various cultural practices were evaluated to develop management techniques to achieve earlier muskmelon production (Cucumis melo 4:45 (345) The Effect of Light and Carbaryl on Thinning ‘Gala· L.) in southern Illinois. Two field experiments were conducted with Apple Trees the first evaluating two cultivars (‘Athena· and ‘Superstar·) on clear plastic mulch with two planting dates (1 April and 1 May), and the Richard Marini* second evaluating ‘Athena· muskmelon at three transplant ages (1, 2 Horticulture, Virginia Tech, 306 A, Saunders Hall, Virginia Tech, and 4 weeks) and two transplant sizes (102.5 cm3 and 280.8 cm3 root Blacksburg, VA, 24061 cell volumes). Regardless of cultivar, the use of clear polyethylene In 2002 and 2003, 5-yr-old ‘Gala·/M.9 trees were sprayed with mulch tended to cause an increase in early season yields, with the 1 carbaryl or water and were covered with shade fabric to provide a range April planting date providing greater early season yields compared to of light for 2, 3, or 4 days beginning when fruit diameter averaged the 1 May planting date. For most years, growers should not expect about 11.0 mm. Incident radiation was measured with a radiometer. early harvests with the May 1 planting date even with clear polyethylene During bloom the number of flowering spurs on two limbs per tree was mulch. The use of clear mulch at the April 1 planting date tended to result recorded and fruit retention was calculated as the number of fruit per in increased early and total-season yields for both cultivars compared 100 flower clusters 6 weeks after treatment. Fruit set for nonshaded to the May 1 planting date. Both transplant age and size influenced trees was lowest in 2001 when several very clouds days followed early-season melon production. The largest cell size produced greater shade cloth removal. When carbaryl was not applied, fruit retention early season yields per acre than the small cell size and two week-old increased linearly with increasing radiation, but the slope was greatest transplants produced greater early season yields compared to one or for 2002. Trees were nearly defruited when cumulative radiation was four week-old transplants. For transplants grown in the large cell size, less than 3.0, 4.0 and 6.0 kW/m2/day for 2, 3, and 4 days, respectively. the week of planting did not greatly influence total season marketable Fruit retention on carbaryl-treated trees increased at an increasing rate melon numbers. However, for the small cell, the two- and four-week as radiation increased for 2 or 3 days. Fruit retention was severely old transplants tended to produce greater total season yields compared reduced when cumulative radiation for 2 and 3 days was less than to one-week old transplants. 6.0 and 10.0 kW/m2/day, respectively. Fruit set on carbaryl-treated trees increased linearly with increasing cumulative radiation for 4 days. Fruit retention was about twice as high with 23.0 kW/m2/day 4:30 Early Season Tomato Defects in Southern New Jersey as with 14.0 kW/m2/day and no fruit were retained when cumulative Michelle Infante-Casella* radiation for 4 days was less than 6.0 kW/m2/day. Agriculture and Resource Management Agents, Rutgers Cooperative Extension, 1200 N. Delsea Drive, Clayton, NJ, 08312 4:00 pm–5:15 pm ORAL SESSION 12 556B Fresh market tomatoes are an important crop in New Jersey with Vegetable Crops—Culture and Management approximately 3,400 acres grown annually for an estimated value of $28,000,000. Gloucester County produces 1,200 acres annually or Moderator: Michelle Infante-Casella about 35% of the state·s total acreage. In Spring 2002, the earliest 4:00 Factors Affecting Broccoli (Brassica oleracea italica) and tomato plantings in this county exhibited fruit defects at all growth Salad White Cabbage (Brassica oleracea var. capitata) stages. Defects were most evident at the mature green stage and were Growing and Their Importance for the Black Sea Region somewhat masked by ripening. However, affected fruit were graded of Turkey either as culls or placed in “commercial” grades. Growers reported as high as 42% commercial grade fruit in their early season packouts. 1 2 Aydin Apaydin* , Hayati Kar The variety predominantly grown in this season and in this region was 1Horticulture, Karadeniz Tarimsal Arastirma Enstitusu-Samsun-Turkey, ‘Sunbrite·. This variety had the most problems that appeared in the form 2Karadeniz Tarimsal Arastirma Enstitusu-PK:39-55001 Gelemen-Sam- of scars, scabs and staining type injury only found on the skin of the sun-Turkey, Samsun, Samsun, 55001, Turkey tomato fruit. Internal examination showed no defects. Other varieties Broccoli (Brassica oleracea italica) and salad white cabbage (Bras- investigated and planted during the same time period, with the same sica oleracea var. capitata) are aid to brassicae family and have great cultural practices showed miniscule or no amounts of fruit defects. Ad- importance in respect to human food and human health. ln the recent ditionally, fields of ‘Sunbrite· planted 2 weeks or more after defective years, importance of broccoli is increasing day by day because of its fields produced excellent quality, non-injured fruit. The first planted importance regarding human health. The Black Sea region is a favor- tomatoes were transplanted in early April when temperatures were able area for the growing of cabbage family in respect to climatical unusually high (32 to 35 °C for 6 consecutive days) and then followed factors of the region. Black cabbage (Brassica oleracea var. acephala), by 4 consecutive days of frost the next week. An assumption was made white head cabbage (Brassica oleracea var. capitata) and cauliflower that the defects were a “pox-like” deformity and were triggered by the (Brassica oleracea italica) have been growing in the region, intensively. combination of environmental factors and genetics. Other factors that Broccoli and salad white head cabbage haven·t been growing in the caused fruit injury in this season were related to high populations of region because they hadn·t been introduced to region farmers so far. Thrips and bacterial canker on some farms. Demonstration of these two cabbages to the region farmers will gain

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4:45 Environmental Effects on total Glucosinolate Concentra- planting and analyzed for ChlA, ChlB and Antho concentration. Each tions in Cabbage (Brassica Oleracea L. Capitata Group) study was repeated twice. Regardless of temperature regimen, cultivar Are Similar Among Genotypes (C) affected the levels of all pigments, while shading (S) affected, primarily, Antho levels. Growth stage (GS) affected ChlA and ChlB Theodore J.K. Radovich*, Matthew D. Kleinhenz, levels. In plants grown at 30 C D/N, levels of ChlA and ChlB were John G. Streeter, A. Raymond Miller significantly greater in ‘Green Vision·than ‘New Red Fire·or ‘Rolina· Horticulture and Crop Science, The Ohio State University, Ohio Ag- but not ‘Galactic·. Under the same temperature regimen, Antho levels ricultural Research and Development Center, 1680 Madison Avenue, were significantly greater in ‘Galactic· than the other cultivars. At Wooster, Ohio, 44691 30 C/18 C D/N, levels of ChlA and ChlB were highest in ‘Green Vi- Glucosinolates are secondary plant compounds of importance to sion·, with similar levels among the remaining cultivars. Under the human health and vegetable sensory quality. Cultivar selection and same temperature regimen, Antho levels were highest in ‘Galactic·, time of planting are management decisions that are thought to affect intermediate in ‘New Red Fire· and ‘Rolina· and lowest in ‘Green the levels of glucosinolates in commercial cabbage. The importance of Vision·. Shading significantly reduced Antho levels in ‘Galactic·and genotype in determining the magnitude and direction of the planting ‘Rolina· under both temperature regimens and ‘New Red Fire· at 30 date effect on cabbage glucosinolate levels is poorly understood, as are °C/18 °C D/N. However, shading tended to increase Antho levels in the environmental factors behind the planting date response. With this ‘Green Vision·. ChlA and ChlB levels tended to decrease with plant in mind, a modified micro-column technique was used to measure total age. In short, quantitative data of pigment concentrations clarified glucosinolate levels in leaf tissue of mature heads of six commercial what was apparent to the unaided eye—namely, that the amount and cultivars and experimental lines of cabbage planted in May and June intensity of green and red color varied among plants subjected to of 2001 and 2002 at the OARDC Vegetable Crops Branch in Fremont, different shading treatments and temperature regimens. Therefore, Ohio. Total glucosinolate levels varied significantly among planting dates data from these and related studies may aid in developing strategies (PD) and genotypes (G), but the PD-x-G interaction was not significant. to achieve targeted levels of pigmentation (especially red) in let- Glucosinolate levels were significantly greater in May-planted cabbage tuce. Additional field and controlled-environment studies currently than in June-planted cabbage in both years: differences ranged from underway employ a unique set of red-leaved varieties for which the 8% to 47%, depending on genotype and growing season. Glucosinolate genetic control of Antho level and distribution is partially known. A levels were highest in ‘Cheers·and lowest in ‘Solid Blue 790·. Higher goal of these studies is to explore relationships among lettuce color mean daily temperatures and a greater incidence of stress temperatures as assessed with instrumentation and the human eye. (>30 °C) during head development in May-planted crops may explain the planting date effects observed here. Also, mean glucosinolate levels 4:15 pm–4:45 pm ORAL SESSION 13 555A were 28% greater in the relatively hot 2002 season, compared to 2001. The data strongly suggest that PD and G act separately to influence total Growth Chambers and Controlled Environments glucosinolate levels in commercially important cabbage cultivars. They Moderator: Gary Stutte also suggest that glucosinolate levels respond to growing conditions 4:15 Nutrient-flowing Wick Culture System (NFW) for Potted during head development, with sub-optimal conditions promoting higher Plant Production and Its Growth and Systematic Charac- glucosinolate levels. Work to isolate the response to specific abiotic environmental factors is underway. teristics Jung-eek Son*, Myung Min Oh, Dong Ho Jung, Yin Ji Lu 5:00 Variety and Shading Effects on Pigment Levels in Lettuce Plant Science, Seoul National University, 103 Seodun, Kwonsun, (Lactuca Sativa) Grown Under Contrasting Temperature Suwon, 441-744, Republic of Korea Regimens The uptake of water and nutrient in potted plants is greatly affected by irrigation conditions, and it influences the plant growth. In this Aparna Gazula*1, Darla G. French2, Matthew D. Kleinhenz3, study, we developed a nutrient-flowing wick culture system (NFW), 3 Joseph C. Scheerens compared the growth and systematic characteristics, and evaluated its 1Horticulture and Crop Science, The Ohio State University, Ohio possibility of commercialization through small and large scale experi- Agricultural Research and Development Center, Gourley Hall, 1680 ments in both university and farmer·s greenhouses. Water contents in Madison Avenue, Wooster, Ohio, 44691, 2Agricultural Education, the root media can be controlled by absorption of nutrient solution Purdue University, 1442 Beering Hall of Liberal Arts & Education, through the wick when irrigated. The water contents of substrate, loss West Lafayette, Indiana, 47907-1442, 3Horticulture and Crop Sci- of nutrient solution, appearance of algae, and growth of Kalanchoe ence, The Ohio State University, Ohio Agricultural Research and blossfeldiana 'New Alter' were observed under various irrigation con- Development Center, Williams Hall, 1680 Madison Avenue, Wooster, ditions (5 irrigation frequencies ×4 irrigation periods). Compared Ohio, 44691 with the existing wick culture systems such as nutrient-containing Color, specifically green and red as related to chlorophyll (Chl) and wick culture system (NCW), NFW could easily control the irrigation anthocyanin (Antho) level, respectively, is particularly important in conditions with growth stage, and thereby could maintain the water lettuce crop quality. Although found in nearly all plants at some stage content of substrate at around 40% for optimum plant growth. The at levels and in distributions influenced by genetics, anthocyanins are water contents were fluctuated from 25 to 40% with respect to irrigation among the least understood of plant metabolites. With this in mind, conditions (frequency and duration). Nevertheless, it gradually went variety and shading effects on ChlA, ChlB, and Antho levels were down to 20% at poor irrigation condition such as 2 times of 10-min examined in four lettuce cultivars at three developmental stages after irrigation a day. The total growth of roots in short-day stage was growth under contrasting temperature regimens in the greenhouse. greatest at 4–5 times of 10-min irrigation, but the weight and height Thirty day-old seedlings of ‘Galactic·, ‘Green Vision·, ‘New Red of shoots increased in proportion to irrigation frequency and period. Fire· and ‘Rolina· were transplanted to 15.2 cm pots and placed in It means that it is possible to control the plant height by reducing the greenhouse rooms maintained at 30 °C day/night (D/N) (study 1) or supply of nutrient solution in the system. Besides, the water loss in 30 °C /18 °C D/N (study 2) temperatures. In each room, three bot- NFW became lower to about one fifth than that in NCW by reducing tomless shade boxes (2.4 m ×1.2 m ×0.91 m) constructed of a single the evaporation of nutrient solution. Algae did not appear in NFW layer of shade cloth attached to a frame of 1.27 cm (outer diameter) while it appeared in NCW. The DO of solution was especially high polyvinyl chloride tubing reduced incoming light intensity 50% and during the irrigation, and salinity of root media was reduced. From contained 9 plants per variety (i.e., a total of one half of all plants in the results, it is concluded that NFW will be one of the promising each room). Leaf tissue was collected at 9, 16, and 23 d after trans- subirrigation systems for potted plant production.

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4:30 Use of Telescience to Remotely Monitor and Control assumption of normality is frequently violated. Finally, general linear FRIDAY pm Wheat Growth Onboard the International Space Station models do not offer adequate methods of accounting for experimental Gary Stutte*1, Oscar Monje2, Gregory Goins3, Sylvia Anderson3 units that do not experience the event within the period of record. Data from units for which the event was not observed, due to loss or harvest, 1 LSSC, Dynamac Corporation, Mail Code DYN-3, Kennedy Space for example, must be either regarded as missing, or interpolated. The 2 Center, FL, 32780, LSSC, Dynamac Corporation, MailCode DYN-3, resulting bias is commensurate to the proportion of units affected, and 3 Kennedy Space Center, FL, 32899, LSSC, Dynamac Corporation, often invalidates attempts at analyzing the data that were collected. Mail Code DYN-3, Kennedy Space Center, FL, 32899 Time–to–event data analysis methods have been thoroughly researched, The Photosynthesis Experiment System Testing and Operations and are well established in fields such as medicine, engineering, and (PESTO) experiment was launched to the International Space Station actuarial science. They are not subject to the limitations that restrict onboard STS 110 (Atlantis) on 8 April, 2002 and returned to earth on the usefulness of general linear models with respect to the analysis of 19 June, 2002 onboard STS 111 (Endeavor), for a total of 73 days in these data. All major statistical software packages include modules or space. Nine 21-day studies were performed to determine the effects procedures designed to implement these methods. time–to–event data of microgravity environment on growth, development and carbon consist of a single time since the beginning of the observation for each assimilation of wheat. The PESTO experiment was performed in the experimental unit, paired with an indicator of whether the event occurred Biomass Production Chamber (BPS; Orbitec, Madison, WI), which or not at that time. If the event was not observed, that record is said to

provided for control of temperature, RH, PPF, and CO2 in four inde- be censored. The time recorded for a censored observation is the time pendently controlled growth chambers. Data from the BPS was sent at which the event ceases to be possible for that particular unit, before from the ISS to an Earth station, and distributed through a web-based it could be observed. All experimental units are observed every time, command and data system (CDS, SSBRP, NASA Ames Research but a datum is recorded only when the event has occurred, or censor- Center, CA). Data from chamber environmental monitoring, control ing takes place. Missing observations are almost always nonexistent. and diagnostic sensors (e.g. air temperature, relative humidity, air pres- The first phase of the analysis of such data is to construct an estimate

sure, CO2 concentration, root zone temperature, PAR) were collected of the cumulative proportion of the population having undergone the at 2 min intervals throughout the mission and displayed in near time event, over the period of record. The product–limit, or Kaplan–Meier through the CDS. In addition, cameras in the BPS provided on-orbit method, is overwhelmingly favored, and easily implemented. Graphing images of plants in each chamber at 2 hour intervals, which were also the resulting step function for each level of the treatments, provides available via CDS, for the duration of the experiment. . The NASA the clearest visualization of the process, as it was observed. Another developed telescience capabilities provided to the PESTO experiment function often considered is the hazard, which is the instantaneous rate allowed continuous monitoring of data at multiple sites (California, at which the event occurred, conditional upon it not having occurred Wisconsin, and Florida), reduced the time required to detect and react yet at that instant. In both cases, since time is the independent variable, to experimental anomalies, increased opportunities for experimental treatment factors are referred to in time–to–event data analysis as covari- observations to be made, allowed near-real time collection, assess- ates. This may be followed by a preliminary test of hypothesis based ment, and analysis of data by PI·s, and provided an invaluable tool on a log–rank or Wilcoxon test, to determine whether any difference for remote commanding of the BPS from Earth. {Research supported was present among treatments. A choice must then be made between through NASA·s Office of Biological and Physical Research Offices parametric or so called semi–parametric regression models. The former Fundamental Biology Program, NCC-027} are often known as Accelerated Failure Time (ATF) models, the latter as Cox regression model or Cox semi–parametric model. All models 4:15 pm–5:15 pm ORAL SESSION 14 551A provide a precise quantification of the effects of treatments, estimates of the expected proportion of occurrence of the event at given times, or Computer Applications in Horticulture of the expected times to reach given proportions, and most importantly, Moderator: Albert J. Sutherland confidence intervals for these estimates. Parametric models are pre- 4:15 Statistical Analysis of Time–to–event Data: Applications ferred when a defined (smooth) functional form describing the process in Horticultural Science over time is desired, the semi–parametric model when it is sufficient to quantify the size and direction of the effect of treatments. Prior to 1 2 3 Jean-Jacques Dubois* , Jason Osborne , Frank Blazich using this last model, however, it is necessary to test the validity of its 1Horticultural Science, North Carolina State University, Kilgore Hall, main assumption, the proportionality of hazards. In other words, the Box 7609, Raleigh, NC, 27695-7609, 2Statistics, North Carolina State relationship between rates of occurrence of the event at various levels University, Patterson Hall Box 8203, Raleigh, NC, 27695-8203, 3Hor- of the covariates, should not change with time. Both graphical and sta- ticultural Science, North Carolina State University, Kilgore Hall Box tistical tests can be performed. Among parametric models, comparisons 7609, Raleigh, NC, 27695-7609 can be conducted using likelihood ratio tests. In addition, a variety Time–to–event data are commonly encountered in horticultural of approaches toward residual diagnostics are available for assessing science. Examples include time to germination, anthesis, or postharvest goodness–of–fit, and should be brought to bear, as well as comparisons senescence. These data are often used to compute the proportion of a of confidence regions. Finally, the biological interpretation of the vari- population that experiences the event within some meaningful period. ous distributions that underlie parametric models should be also be an Corresponding examples would be percentage germination, flower- important criterion in the choice of a particular parametric model. Use ing, or senescence, within a set period. Cultivars, irrigation regimes, of these procedures in horticultural science greatly increases both the or temperature are familiar examples of treatments whose effect on efficiency and precision of data analysis in the study of developmental time–to–event we might be interested in quantifying. In the plant sci- and phenological processes. ences, such data are customarily analyzed using normal theory general linear models, including analysis of variance and linear regression. 4:30 GIS Application in Determination of Suitable Area for However, this approach has three limitations. First, although data Rainfed Almond (Case Study, Azarbaijan Province) may be recorded at several points between initiation and termination of an experiment, only one point in time can be taken into consider- Hojjat Yazdanpanah* ation at once: time for a fixed proportion (e.g. 50%, 90%, or 100%) Geography, Teacher Training University, Mofatteh, Tehran, Tehran, Iran to experience the event, or alternatively, proportion of a population Limitations in soil and water resources together with irregular rate having experienced the event by some fixed time. The entire course of population increasing, cause that we choose a usefull landuse in of the process over time is not explicitly examined. Secondly, given our available resources. In order to do this, climatic investigations are that the distribution of event times is often nonnormal, the underlying necessary. The objective of this study was classification of Azarbaijan

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Sharghi Province in aspect of climatic potential of Almond in dryland 4:30 pm–5:30 pm WORKING GROUP MEETING 558B farming. For this purpose, the precipitation and evaporation data as Emeritus (EMER) Working Group well as temperature parameters of ten meteorological stations of area were collected and analysed. The following indices were selected for Chair: J. Benton Storey Almond in dryland farming: 1) probability of chilling occurrence on bud and flower of Almond; 2) probability of rainfall greater than 250 4:30 pm–5:30 pm Westin-Newport/Washington Room mm; 3) spring and summer precipitation to annual precipitation ratio; Student Mixer 4) probablity of occurrence of growing degree days greater than 3500 G.D.D (base temperature 0 °C); and 5) amount of available moisture index. For each of above parameters a coverage layer was prepared in 5:00 pm–5:30 pm BUSINESS MEETING Ballroom B GIS environment,in the second stage five mentioned coverage layers Growth Chambers & Controlled Environments (CE ) were crossed and overlapped to obtaining the agroclimatic map of area Working Group .Finally agroclimatic map reclassed to highly favorable, favorable, weak Chair: Chieri Kubota and not suitable area. 5:00 pm–5:30 pm BUSINESS MEETING 555B 4:45 A New e-Extension Outreach Blending Weather Data and Genetics and Germplasm (GG) Working Group Traditional Educational Approaches Chair: Peter Cousins Albert Sutherland*1, J.D. Carlson2, Leila Milne-Hickman3, 4 5 Michael Wolfinbarger , Stdrovia Blackburn 5:30 pm–6:30 pm POSTER SESSION 6 Ballroom A 1 Biosystems and Ag Engr, Oklahoma State University, 828 West (Location numbers for the posters within the Choctaw Ave, Chickasha, OK, 73018-2310, 2Biosystems and Ag Engr, Poster Viewing Area are in parenthesis) Oklahoma State University, 214A Ag Hall, Stillwater, OK, 74078- 6016, 3Biosystems and Ag Engr, Oklahoma State University, 111 Ag Teaching Horticulture to Diverse Constituencies Hall, Stillwater, OK, 74078-6016, 4Oklahoma Climatological Survey, University of Oklahoma, 100 East Boyd St, Suite 1210, Norman, (370) A Model to Integrate University and Community OK, 73019-1012, 5Oklahoma Climatological Survey, University of College Horticulture Curricula Oklahoma, 100 E. Boyd St., Suite 1210, Norman, OK, 73019-1012 Rolston St. Hilaire*1, James Thompson2 Oklahoma is in a unique postion to bring together weather in- 1Agronomy and Horticulture, New Mexico State University, Box 30003, formation, horticultural decision support, and university extension Las Cruces, NM, 88003, 2Facilities Maintenance Technology, Dona Ana resources as an online, working example of the e-Extension concept. Branch Community College, Box 30001, Las Cruces, NM, 88003 This website, activated in January 2003, combines weather data and Each year, a declining number of students choose careers in agricul- online access to traditional extension resources. The site relies on ture. Therefore, new approaches in agricultural instruction need to be data from the Oklahoma Mesonet, one of the world·s finest weather created to attract students to agriculture. Two New Mexico educational monitoring systems. This network boasts 110 plus towers, distributed institutions, Doña Ana Branch Community College-a two-year com- across Oklahoma, recording research quality weather data in 5-minute munity college and New Mexico State University-a four-year Univer- increments. Collected data is updated every 15 minutes online, and sity, have integrated collaborative and experiential learning projects displayed in graphical and text formats. The site includes pecan and in a redesigned landscape construction course. The objective of this watermelon pest management products. The dynamic weather data educational approach is to model a system that facilitates the seamless is strengthend by ready access to extension horticultural production integration of compatible curricula from a community college and a resources organized by commodity. At the same time, the static exten- university. In the midterm course evaluation, 67% of students rated the sion resources provide an educational opportunity, when the website combining of a university and community college class as above average user is most open to the learning process. or excellent. Ninety four percent of the class rated classroom materi- als and laboratory activities supported learning as excellent. Students 5:00 Development of Instant Chlorophyll and Nitrogen Diag- valued the experiential learning projects and would highly recommend nostic System for Intact Plant Leaves the course to their peers. In this redesigned course, ethnic minorities Pinghai Ding*1, Leslie H. Fuchigami2, Thomas K. Plant3 now constitute 40% of the class, suggesting that this model has the potential to retain a large number of minority students in landscape 1Horticulture, Oregon State University, ASL 4017, Corvallis, Oregon, horticulture. We conclude that this collaborative approach for teaching 97331, 2Horticulture, Oregon State University, ALS 4017, Corvallis, landscape horticulture is likely to enhance agricultural education and Oregon, 97331, 3Electrical and Computer Engineering Department, foster a seamless educational experience for students who transition Oregon State University, Owen Hall 220, Corvallis, Oregon, 97331 from a community college to a university. Fresh leaves of apple (‘Fuji·/M26, ‘Gala·/M26, ‘Jonagold·/M26 and ‘Liberty·/M26), ‘Nonpareil·almond, Western Redbud, and Populus spp. were scanned by using FOSS Near Infrared (NIR) System Model-6500 (371) Improving Biometrical Reasoning in Agricultural from the wavelength of 400 to 2500nm. The chlorophyll and nitrogen College Education contents of the scanned leaves were analyzed by using standard chemical Raúl E. Macchiavelli, Linda Wessel-Beaver* methods. The optimum wavelengths for measuring leaf chlorophyll and Dept. of Agronomy and Soils, University of Puerto Rico, P.O. Box nitrogen were obtained by using statistical methods to find the relation- 9030, Mayaguez, PR, 00681-9030 ship between the FOSS NIR scanned results and the chemical results. The Hispanic-Serving Institutions Education Grants Program of the Meter prototype for determining intact leaf chlorophyll and nitrogen were USDA Cooperative State Research, Education, and Extension Service produced by Tom Plant based on the selected wavelength and the test (CSREES) promotes and strengthens the ability of Hispanic Serving results. The laboratory and field test results showed that the prototype Institutions (HSIs) to carry out higher education programs in the food was more accurate in determining chlorophyll and nitrogen contents and agricultural sciences. The Mayaguez Campus of the University of than all other commercial meters tested. In addition to the prototype, a Puerto Rico is a land grant institution and the second largest campus on software was developed to convert the meter readings of the prototype the island. It serves an almost exclusively (97%) Hispanic clientele, the and the other commercial meters including SPAD meter, CCM-200 and majority of which are of limited economic resources. The College of CM-1000 directly into chlorophyll and nitrogen contents.

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Agricultural Sciences (CAS) integrates the Faculty of Agriculture, the (373) Design of CD-rom Based Course Materials for Inter- Agricultural Experiment Station, the Agricultural Extension Service, disciplinary Course on Medicinal Plants for Horticulture FRIDAY pm and the Office of International Programs in Agriculture. As part of the and Non-horticulture Majors institutional commitment to provide students a quality education, a Usha Palaniswamy* strong emphasis is placed on continuously updating the educational tools and offerings to meet current needs. The CAS was awarded a grant Allied Health, University of Connecticut, Unit 2101, 358 Mansfield from the CSREES-HSI Program for 2001-2003. The goal of this grant Road, University of Connecticut, Storrs, CT, 06269 was to strengthen agricultural students· and teachers· knowledge of, There is an increasing interest in herbs and herbal medicines and ability to use, biometrical concepts by involving undergraduates among all student populations. The Course AASI-AH 214 Medicinal in current research activities, and by preparing faculty from different plants of Asian origin and culture was developed for horticulture and biological areas to be better able to incorporate biometrical ideas into non-horticulture majors and offered for the first time during the winter their courses and research. Grant monies have enabled the CAS to equip intersession, 2003. A CD-ROM was developed to aid student learn- a Biometry Computer Laboratory with 16 computers, various statistical ing in this course. Since the course is open to all majors, the course packages, and a Smart Board® (an interactive electronic board). Eleven material was written to include illustrations, historical perspectives, undergraduate students have participated in research programs that cultivation practices, botany, traditional uses and current status and emphasized data summary, analysis and presentation. A total of 24 health value of 108 plant species supported by scientific studies and professors, researchers, extensionists participated in workshops during references. Botanical and medical glossaries were also included to help the summer of 2002 (and an additional group will participate in 2003). the students understand the terms unique to botany and medicine. The Researchers and extensionists were encouraged to participate in the CD-ROM also contained active links to numerous internet web-sites workshops since many of those faculty interact with undergraduate that the students could access for more information about any specific students either by teaching formal courses or supervising summer plant species. The CD-ROM is published by the UK based CPL Press, practicals for students from the CAS. Each workshop lasted 2 days and distributed in the United States by A & M distributors. and included discussions, on-hand computer practice and examples on basic statistical ideas (sampling, experimental design, summary (374) Horticultural Plants and Ecology of the New Jersey statistics, graphics, simple inference) that could be incorporated into Shoreline: Episode 108 for the “If Plants Could Talk” the curriculum of college courses taught by participants. Given the Gardening Television Series for NJN PBS interest of some of the participants, ideas to incorporate statistics into other non-formal teaching opportunities (such as extension services, William Hlubik*1, Nicholas Polanin2, Russell Blair3, field demonstrations, etc.) were also discussed. Gef Flimlin4, Madeline Flahive-DiNardo5, Richard Weidman6, David Smela7, James Marko8 (372) Using Computer Simulation Software to Enhance 1Agricultural and Resource Management Agents, Rutgers, The State Student Learning Univ., 390 George Street, 8th floor, New Brunswick, NJ, 08901, 2Agricultural and Resource Management Agents, Rutgers, The State Kent Kobayashi* Univ., RCE of Somerset County, 310 Milltown Road, Bridgewater, Tropical Plant & Soil Sciences Dept., University of Hawaii, 3190 NJ, 08807, 3Agricultural and Resource Management Agents, Rutgers, Maile Way, St. John 102, Honolulu, HI, 96822 The State Univ., RCE of Cape May County, 4 Moore Road, Cape TPSS 601 Crop Modeling is a graduate level course covering the May Court House, NJ, 08210, 4Agricultural and Resource Manage- principles of modeling crop growth and development, model types, ment Agents, Rutgers, The State Univ., RCE of Ocean County, 1623 techniques, and simulation. Students learn about modeling the influence Whitesville Road, Toms River, NJ, 08755, 5Dept. of Agricultural of climate/environment on the phenology and growth of horticultural and Resource Management Agents, Rutgers, The State Univ., RCE crops. Scientific articles are the main source of information used in the of Union County, 300 North Avenue East, Westfield, NJ, 07090, course. However, as useful as these articles are, having only readings 6Agricultural and Resource Management Agents, Rutgers, The State limits the students learning experience. To enhance active learning Univ., RCE of Middlesex County, 390 George Street, 8th Floor, New by students, a computer simulation software was introduced into the Brunswick, NJ, 08901, 7Agriculture, Rutgers Cooperative Extension course. Initially, an IBM simulation program called CSMP (Continuous of Middlesex County, RCE of Middlesex County, 390 George Street, System Modeling Program) running on an IBM mainframe computer 8th floor, New Brunswick, NJ, 08901, 8Agricultural and Resource was used. This required students to learn program coding and syntax. Management Agents, Rutgers, The State Univ., RCE of Middlesex Output from simulation runs was limited by the kinds of graphs CSMP County, 390 George Street, 8th floor, New Brunswick, NJ, 08901 produced. Yet, CSMP gave the students the opportunity to learn how This thirty-minute television episode captures the unique ecology to write, debug, and run a simulation program and to interpret and of the New Jersey shoreline and its impact on both farmers and the discuss the results. Later, as simulation software became more avail- general public. The episode is part of the “If Plants Could Talk” , able on personal computers, the simulation software STELLA (High educational gardening series for New Jersey Network(NJN) Public Performance Systems) was used. Unlike CSMP, this software presents Television. This episode aired on NJN on June 1, 2002 at 12:30 PM. a graphical user interface to the students. It is based on the principle Nielsen ratings were 30% higher than a comparable national garden- fi of rst developing a relational diagram of the system using the state ing program normally aired during the same time slot. The potential variable approach. Students construct the relational diagram with icons viewing audience is 8 million people, which includes all of NJ and representing state variables, rate variables, and so on with arrows and parts of PA, DE, NY and CT. flows representing interrelated components. An advantage of a software such as STELLA, compared to CSMP, is that the students need to first formalize their conceptual model into a more formal model. Then, (375) Nebraska·s Senior Farmers· Market Nutrition students supply the equations and values of parameters and constants. Program STELLA enables the rapid and easy running of multiple simulations Laurie Hodges*1, Dan Korber2, Tammie Scholz3, with attractive graphs and tables. Simulation software in a crop mod- Susan Helmink4 eling course has enabled students to formulate, write, and run crop 1Agronomy & Horticulture, Univ. of Nebraska, 377 Plant Sciences- models, thus supplementing their readings. Simulation software has UNL, Lincoln, NE, 68583-0724, 2Agriculture Promotion & Devel- made possible active learning by providing hands-on experience with opment, Nebraska Dept. of Agric., PO Box 94947, Lincoln, NE, crop modeling, thereby enhancing student learning. 68509-4647, 3Health & Human Services, Nebraska Dept. of Agric., PO Box 95044, Lincoln, NE, 68509-5044, 4Agriculture Promotion

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& Development, Nebraska Dept. of Agric., PO Box 94947, Lincoln, New Jersey, 08901 NE, 68509-4947 The “If Plants Could Talk” (IPCT) educational web site at http: In 2001, USDA solicited state proposals for pilot programs for the //ifplantscouldtalk.rutgers.edu, was created in February 2000 to provide Senior Farmers· Market Nutrition Program (SFMNP) with two main more detailed information for the IPCT gardening television series objectives 1) Increase consumption of fresh fruits and vegetables by for NJN PBS. The web site contains fact sheets, slide shows, virtual low-income elderly persons and 2) increase purchases from direct tours, streaming videoand listings for arboretums and “pick-your-own” marketers of fresh produce, assisting many small, diversified farmers. farms in New Jersey. Many of theeducational components contain SFMNP continued in 2002 and became part of the Farm Security and individual evaluations. An on-line survey revealsthat over 90% of Rural Investment Act of 2002 [aka The Farm Bill] funded at $15M/year users would visit the site again and would recommend the site tooth- ensuring its continuation through 2008. Through cooperative program ers. Web Trends data analysis software indicates approximately 5 development involving the University of Nebraska Cooperative Ex- million hits todate. One of the most popular downloaded documents tension, the Nebraska State Department of Agriculture/Division of was the “pick-your-own” list for New Jersey farmers. This popular Promotion & Development, and the Nebraska Department of Health web site provides practical research-based informationon environ- & Human Services/Division on Aging, the state received funding mentally sound horticulture for extension clientele throughout the for the SFMNP Pilot Program in 2001 and regular program in 2002. state and region. Participants included 44 farmers· markets, over 100 distribution centers (primarily senior centers with commodity food distribution (377) The New Online Tools for Extension Education in centers used in areas without senior centers). Eligible seniors received Small Fruits coupons monthly at distribution centers to purchase fresh produce directly from growers. With at least 6% of the population classified Wei Qiang Yang* as low-income elderly, and over two-thirds of the state population Horticulture, North Willamette Res & Ext Center, 15210 NE Miley located in three counties (essentially Lincoln and Omaha),and the Rd., Aurora, OR, 97002 balance of the population widely distributed in significantly rural The Northwest Berry and Grape Information Network (http: counties, accessibility and equal opportunity to participate in the //berrygrape.oregonstate.edu), created by Dr. Edward Hellman in program were primary concerns in designing the program. Although 1995, is recognized as the most comprehensive information and com- the state has approximately 44 regularly scheduled farmers·markets, munications resource for small fruit research, production, market, and many are very loosely organized, especially in the many smaller, more extension education in the Northwest. It has now become a cooperative rural communities. Transportation is a critical issue for low-income program among Oregon State University, Washington State University, elderly in rural areas. Through creative collaboration among agen- University of Idaho, and USDA. To further facilitate the information cies and individuals, a highly successful program developed which retrieval process, new features such as a sitemap and a functioning achieves the USDA program objectives. Each year, senior participants menu bar were added to the website. Using Java Script, a scrolling report the program increased consumption of fresh, nutritious pro- window has been recently added to the index page for posting the duce (83% in 2001; 94% in 2002) and direct marketers of produce latest information related to small fruit production. Online decision increased sales and their market customer base. Coupon redemption making tools such as grape yield estimation and spray calculator are rate exceeds 80%. Linkages between producers and communities also made available. While these online technologies are taking exten- were strengthened through greater interaction and communication sion program delivery to a new epoch, a survey indicated that some initiated by the USDA-SFMNP program. Extension programing to growers still rely on the traditional extension means to get production further develop farmers· markets and additional producers is neces- information. It seems that the online delivery of extension programs in sary to ensure access to fresh, locally-grown produce by Nebraska·s small fruit production may not become fully effective until the majority rural, low-income elderly. of growers become tech-savvy.

(376) The “If Plants Could Talk” World Wide Web Site: (378) Chicago Botanic Garden Plant Evaluation Web Site An Effective Tool for Horticultural and Environmental Mark R. Rudy* Education Ornamental Plant Research, Chicago Botanic Garden, 1000 Lake Cook 1 2 William Hlubik* , Nicholas Polanin , Road, Glencoe, IL, 60022 3 4 Madeline Flahive-DiNardo , Sean Convery , The Chicago Botanic Garden·s Plant Evaluation Program is one 5 6 7 Richard Weidman , William Sciarappa , Daniel Kluchinski , of the largest and most diverse of its kind in the country. Evaluating David Smela8, James Marko4, Bruce Barbour9 over 1,400 taxa of perennials, vines, groundcovers, shrubs and trees 1Agricultural and Resource Management Agents, Rutgers, The State totaling over 10,000 plants, the Program offers useful and timely data Univ., 390 George Street, 8th floor, New Brunswick, NJ, 08901, on the best adapted plants for the Chicago Region and Upper Midwest. 2Agricultural and Resource Management Agents, Rutgers, The State Green industry professionals and home gardeners alike rely upon the Univ., RCE of Somerset County, 310 Milltown Road, Bridgewater, Program to deliver recommendations of superior garden plants based NJ, 08807, 3Dept. of Agricultural and Resource Management Agents, upon comparative multi-year trials. The Garden·s primary outlet for Rutgers, The State Univ., RCE of Union County, 300 North Avenue plant evaluation data, Plant Evaluation Notes, is published following East, Westfield, NJ, 07090, 4Agricultural and Resource Management the completion of trials and typically focuses on a single genus or trial Agents, Rutgers, The State Univ., RCE of Middlesex County, 390 group. In a new project funded by the Institute for Museum and Library George Street, 8th floor, New Brunswick, NJ, 08901, 5Agricultural Services, the Chicago Botanic Garden has developed a Plant Evalua- and Resource Management Agents, Rutgers, The State Univ., RCE tion Web Site, which provides timely annual data on approximately of Middlesex County, 390 George Street, 8th Floor, New Brunswick, 1,000 taxa of plants currently in the Program, complete with images NJ, 08901, 6Agricultural and Resource Management Agents, Rutgers, of plants from each taxon. Evaluation record summary pages provide The State Univ., RCE of Monmouth County, 20 Court Street, Freehold, both scientific and common name, growth form (i.e. perennial, vine, NJ, 07728, 7Agricultural and Resource Management Agents, Rutgers, shrub, tree) and site description along with an annual rating of plant The State Univ., RCE of Mercer County, 930 Spruce Street, Trenton, performance. Specific data categories include ornamental aspects (i.e. NJ, 08648, 8Agriculture, Rutgers Cooperative Extension of Middlesex flower period, flower color, flower size, plant height/width), cultural County, RCE of Middlesex County, 390 George Street, 8th floor, New problems, disease and pest problems, potential invasiveness, winter Brunswick, New Jersey, 08901, 9Agricultural and Resource Management injury and maintenance regime. Each of these categories are presented Agents, Rutgers, The State Univ., 88 Lipman Drive, New Brunswick, in a user-friendly summarized format. In addition to annual evaluation

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data, plant taxa that have completed the multi-year evaluation period management course. The course emphasizes entrepreneurial skills, ac- FRIDAY pm are given a cumulative performance rating, which is displayed at the top counting principles, budgeting, investment decision-making, planning, of the record page. The Plant Evaluation Web Site is fully searchable and plan implementation for the green industry. To aid in the learning by rating, scientific and common name, growth form, flower period, process each student manages a computer simulated diverse horticul- flower color and plant size. A comprehensive, summarized dataset ture business (HortBusSim) over a number of yearly cycles during the on a significant number of plant taxa, coupled with searchability and course. At the beginning of the course, the student entrepreneur decides ease of use, make this unparalleled web site an invaluable resource which enterprises to operate, the level of each enterprise, and how each for horticultural professionals, educators and home gardeners in the enterprise will be operated. At the end of each yearly cycle the student Upper Midwest and possibly throughout North America. experiences the results of his/her decisions. Chance elements that are beyond the control of any manager (weather fluctuations, higher/lower (379) The Effectiveness of Extended Workshops in Con- than expected selling prices, etc.) are incorporated in the process. The student completes an analysis of the simulated business activity at the veying In-Depth Course Content end of each yearly cycle, including common production and business 1 2 3 Cynthia McKenney* , Wayne Mackay , Steven George summary documents: production records, inventory, balance sheets, 1Dept of Plant and Soil Science, Texas Tech University and Texas A&M cash flow and income statements. He/she then plans and implements Research and Extension Center, 17360 Coit Road, Dallas, TX, 75252, the next yearly cycle of business operation based on the previous year 2Texas A&M University, Research and Extension Center- Dallas, 17360 performance. At the beginning of the course students have limited Coit Road, Dallas, TX, 75252, 3Texas A&M University, Research and knowledge of business management, consequently their management Extension Center- Dallas, 17360 Coit Road, Dallas, Texas, 75252 decisions are more intuitive, resulting in highly uncertain outcomes Highly motivated, experienced professionals have a limited amount in HortBusSim. As the course progresses and students learn business of in-depth continuing education available for their use. The Advanced management skills, they apply these management tools to make more Horticultural Studies Program offers challenging extended workshops scientifically sound decisions resulting in more certain outcomes in designed to expand the participant·s scientific and professional horizons. HortBusSim. The course content is offered at a post-baccalaureate level of instruc- tion utilizing top professionals from universities, botanic gardens, (382) Zinc Deficiency in Pecan—Multidisciplinary Case and leading retail/wholesale nurseries. Over the past three years, the Study for Upper Division/Graduate Level Mineral Nutri- effectiveness of these 4-day short courses has been studied using a pre- tion Course course post-course exam format coupled with a simple demographic survey. In each of the workshops evaluated, there was a significant D.S. Rodriguez* improvement in the general knowledge of the participants. A profile Agronomy & Horticulture, New Mexico State University, Box 30003, of the average workshop participant and the frequency distribution of Las Cruces, NM, 88003 the repeat participation levels will be provided. Cultivated pecan trees have an arduous battle against zinc (Zn) deficiency in the semiarid southwestern USA. The practice of repeated (380) Industry Survey Identifies Priorities for Teaching Zn spray applications has proven highly successful in prevention of Zn Design and Construction topics to Students in Landscape deficiency in pecan. However, less attention has been focused on why pecan is highly vulnerable to Zn deficiency, while in similar growing Management conditions, other tree species do not appear to be at-risk. This under- 1 2 3 4 Dan Stearns* , Jaina Craddock , Martin McGann , Larry Kuhns appreciated angle of pecan Zn deficiency encourages a multifaceted, 1Horticulture, Penn State, 306 Tyson Bldg., University Park, PA, multidisciplinary, active learning environment strongly focused on 16802, 2Horticulture, Penn State, 102 Tyson Bldg., University Park, scientific study of mineral nutrition. The five focus groups include 1) PA, 16802, 3Horticulture, Penn State, 305 Tyson Bldg., University metabolic roles of Zn in pecan trees, 2) macroscopic and microscopic Park, PA, 16802, 4Horticulture, Penn State, 304 Tyson Bldg., Uni- consequences of Zn deficiency in pecan, 3) why pecan appears to be versity Park, PA, 16802 uniquely susceptible to Zn deficiency, 4) short-term solutions and The landscape contracting program at Penn State has a history of economics, and 5) long-term solutions and barriers. Peer teaching engaging industry personnel in decisions regarding curriculum devel- enhances group-to-group interaction over that of traditional lecture opment. When planning a new course on design/build principles for format, such as in identifying the underlying physiological basis for students enrolled in a landscape management option, faculty sought the visually observable Zn deficiency symptoms (groups 1 ×2), or in dis- input of owners/managers in landscape companies with maintenance cussing whether or not pecan roots have evolved with morphological divisions. A survey instrument was mailed to 227 recipients, requesting traits amenable to the primary mode of Zn transport in semiarid soils that they rate the importance of 17 topics identified by faculty as having (groups 3 ×5). This case study offers students opportunity for voicing potential for inclusion in the course. Demographic information was also skepticism over published literature, and for practicing the identification solicited. Upon analysis, the topics were separated into 3 groups: most of “gaps” in research that could ultimately lead to long-term, low-input important, important, and least important. The most important topics solutions to problems in mineral nutrition. Also, the exercise allows were: client relations, influence of maintenance on design, construction students to visualize how problems in mineral nutrition cross over and plans & details, and design elements & principles. Demographic differ- “feed back” between professional lines, including consultants/growers, ences did not affect how industry personnel rated the topics. pure scientists, and the fields of soil and water science, root biology, biochemistry, plant propagation, and molecular genetics. (381) Business Management Training for Horticulture Students (383) The Horticultural Science Program at Penn State Berks Campus Terry Ferriss*1, Gerald Nolte2, Nate Splett2, Lanny Neel1, Brian Smith1 Michael Fidanza*, David Sanford 1Department of Plant and Earth Science, University of Wisconsin-River Horticulture, Pennsylvania State University, Penn State Berks Campus, Falls, 410 So. Third Street, River Falls, WI, 54022, 2Department of Tulpehocken Road, Reading, PA, 19610 Agricultural Economics, University of Wisconsin-River Falls, 410 The Berks Campus is the only satellite campus of the Pennsyl- So. Third Street, River Falls, WI, 54022 vania State University that offers a program in horticulture and the Horticulture and Agricultural Economics faculty at the University agricultural sciences. At Penn State Berks Campus, located in Read- of Wisconsin-River Falls collaborated to create a horticulture business ing, Pennsylvania, students can begin their academic career in any of

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the baccalaureate degree programs offered by Penn State University·s (8) Changes of Polyphenol Oxidase and Peroxidase Activ- College of Agricultural Sciences. In addition, Penn State Berks Cam- ity During Growing Season in Seven Asian Pear Cultivars pus offers an Associate Degree in Agricultural Business with options Wol-Soo Kim*, Xiu-Yu Wu, Soon-Ju Chung in both Food and Ornamental Horticulture. Four agricultural science faculty members are located at the Berks Campus, where they advise Department of Horticulture, Chonnam National University, 300 Yong- undergraduate students and teach undergraduate courses in agricultural bong-dong, Bucku, Gwangju, 500-757, Republic of Korea economics, food science, horticulture, and crop and soil sciences, as This study was carried out to determine the relationship of polyphenol well as other courses. Those faculty also engage in variety of research oxidase (PPO; 1,2-benzenediol:oxygen oxidoreductase; EC 1.10.3.1) and extension projects to support the College of Agricultural Sciences and peroxidase (POD; EC 1.11.1.7) activity and skin browning which was effort in Southeastern Pennsylvania. showed in some Asian pear cultivars on storage and long transportation. The activity of PPO and POD, known as cause of skin browning, was 5:30 pm–6:30 pm POSTER SESSION 7 Ballroom A investigated in skin-browning site of growing fruit on tree. The activity of PPO and POD was investigated in fruits and leaves of three sensitive (Location numbers for the posters within the cultivars (Niitaka, Imamuraaki and Chuwhangbae) and four resistance Poster Viewing Area are in parenthesis) cultivars (Kosui, Shinsui, Hosui, Hwangkumbae and Gamcheonbae) during growing season. In the skin-browning part, PPO activity was Pomology–Physiology/Plant Growth Regulators higher about 3 folds than non-browning, but POD activity was not (6) Branch Training Angles for the Vegetative and Repro- showed significant difference. PPO activities were similar at 80 days ductive Organ Development and Photosynthesis Activities after full bloom in young fruit but then increased steadily during growth in ‘Fuji· Apple Trees in fruit skin. However, PPO activity was the highest in leaves at 130 days after full bloom but then decreased steadily during growth. PPO activi- Hyun-Hee Han*, Yong-Koo Kim ties of sensitive cultivars were higher than that of resistance cultivars. Horticulture, Kyunghee University, 1 Sechonri Kiheung, Yongin, Kyonggi, 449-701, Republic of Korea (9) Effect of Diphenylamine Dipping on Skin Browning This experiment was carried out to find out some fundamental Development and Changes of Polyphenol Oxidase and phenomena and physiology of apple tree responses to artificial ma- Peroxidase Activity in Asian Pear nipulation of branch angles and following results were able to observe. Pending branches performed earlier canopy development with proper Wol-Soo Kim*, Xiu-Yu Wu, Soon-Ju Chung shoot growth and tree height for high-density orchard systems. Pending Department of Horticulture, Chonnam National University, 300 Yong- branches had larger amounts of chlorophyll and water conductance, and bong-dong, Bucku, Gwangju, 500-757, Republic of Korea higher transpiration rate than horizontal branches in the leaves of trained This study was carried out to determine the relationship of poly- branches. Pending branches showed thicker ratio of bark against wood phenoloxidase (PPO) activity and skin browning which was showed than horizontal ones. Pending branches demonstrated more advanced in three Asian pear cultivars (Niitaka, Chuwhangbea, Imamurraki) on stages of flower bud development than horizontal and slanting ones. storage and long transportation. Pre-drying treatment was carried out Pending branches had larger number of lateral shoots than horizontal or 1, 3, 5, 7 days after harvest at room temperature. Dipping treatment of slanting branches, implicating that more flower buds could be developed dipheylamine (DPA) was carried out with 1500 mg/L DPA solution. from pending branches. There was a certain relationship between the Effect of DPA and pre-drying on inhibition of skin browning was in- shoot growth of main stem and scaffold branches. These facts mean vestigated during storage. Skin browning rate and PPO activity was that the tree height could be controlled by growth of scaffold branches. significantly decreased by dipping treatment of DPA in three cultivars. In conclusion skin browning was associated with PPO activity more (7) Analysis of Fruit Growth Curves of Eight Sweet Cherry than POD and then dipping treatment of DPA could be useful methods Cultivars to decrease skin browning. Anita Nina Azarenko*, Annie Chozinski (10) Factors Influencing Preharvest Drop of Apples Department of Horticulture, Oregon State University, Ag and Life Sciences 4017, Corvallis, OR, 97331-7304 Duane Greene*, Wesley Autio, James Krupa Sweet cherry [Prunus avium (L.) L.] fruit exhibit a double sig- Plant and Soil Sciences, University of Massachusetts, Bowditch Hall, moidal growth curve, which is characterized by three primary stages Amherst, MA, 01003 that are often designated as Stages I, II, and III. Yet, published data Astudy was initiated to gain a better understanding of the process of on the relationship of the three growth stages of sweet cherry fruit preharvest drop in apples and the factors that contribute to it. Five paired to time of harvest is lacking. Therefore, we completed a study that trees of ‘McIntosh·were selected in 2001 and 2002 and five paired trees analyzed the differences between growth curves of eight sweet cherry of ‘Delicious· were selected in 2002. Dropped fruit were counted and cultivars that have varying maturity dates. ‘Cristalina·, ‘Sonata·, ‘San- removed at 8 AM and 3PM daily under one of the paired trees and fruit dra Rose·, ‘Bing·, ‘Regina·, Sweetheart·, ‘Staccato· and ‘Symphony· weight, red color, seed number, starch index, and internal ethylene (only fruit were selected on 6 May 2001 and 24 May in 2002. Repeated fruit in 2002) were measured on individual fruit. At the same time 10-apple diameter measurements were taken 2-3 times per week until harvest. samples were randomly harvested from the other paired tree and evalu- The first derivative f· between measurement dates provided relative ated similarly to dropped fruit. Sampling continued until most fruit were growth rates. The second derivative f·· was used to identify end points on the ground. Fruit weight had no consistent influence on drop. Drop for each stage of development. When f·· described a minimum for ‘McIntosh·fruit had more red color and fewer seeds than those harvested function f, this corresponded to the smallest y-value and the end of from the trees in 2001 but were different in 2002 . Dropped fruit of both Stages I and II. The largest y-value in the range of f corresponded to cultivars had higher starch index (greater starch hydrolysis) and higher the absolute maximum of f··. After identifying the ending/beginning internal ethylene in 2002. These data will be discussed in relation to points in the data, mean relative growth rates for each stage were cal- the concconcept that preharvest drop in apples is initiated by ethylene. culated. Based on this approach to growth curve analysis, the duration of Stage II appeared to vary the greatest across genotypes and was (11) Response of Muscadine Grape (Vitis rotundifolia Mi- longer as cultivars matured later. Additionally, the rate of fruit growth chx) to the Growth Regulators CPPU and Gibberellic Acid during stage III tended to be slower for cultivars that matured later. Stephen J. Stringer*, Donna A. Marshall, Blair J. Sampson

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USDA ARS, Small Fruit Research Station, 306 South High Street, application of LPA may stimulate the ripening in the portion of trees FRIDAY pm Poplarville, MS, 39470 that have deceased amount of light. Experiments were conducted during 2001 and 2002 at McNeil, MS, with muscadine grapes to determine how combinations of the growth 5:30 pm–6:30 pm POSTER SESSION 8 Ballroom A regulators gibberellic acid (GA ) and N-(2-chloro-4-pyridyl)-N -phenyl- 3 · (Location numbers for the posters within the urea (CPPU) affected fruit set and berry size in six insect-pollinated and Poster Viewing Area are in parenthesis) pollinator-excluded, mature, field- grown pistillate cultivars including ‘Black Beauty·, ‘Fry·, ‘Higgins·, ‘Hunt·, ‘Summit·and ‘Sweet Jenny·. Nursery Crops—Environment and Growth Management

In 2001, GA3 was applied to flower clusters pre-bloom and was fol- lowed by applications of CPPU applied at 50% bloom alone or again (67) Integrating Photosynthetic Active Radiation in Tree Canopies: A Comparison of Established Methods to a when fruit had developed to a size of 6-8 mm. The GA3 concentration was 20 mg·L–1 and the CPPU concentrations were either 6 mg·L–1 or Novel Fiber-optic-based System 12 mg·L–1. A control treatment without either growth regulator was also William Bauerle*, Joseph Bowden included. In 2002, GA (20 mg·L–1) was applied either alone (pre-bloom) 3 Horticulture, Clemson University, 176 Poole Ag. Center, Clemson, or in conjunction with single applications of either 12 or 24 20 mg· –1 L SC, 29634-0375 CPPU at 6-8 mm berry size. CPPU was also applied alone at these same use rates and application timing and a control treatment without In comparison to the most economic photoelectric sensors with growth regulators was also included. Results of the 2001 study showed spectral responses in the photosynthetically active radiation (PAR) re- significant variation among cultivars in response to the growth regulator gion, namely silicon cells (Si) and gallium arsenide phosphide (GaAsP) treatments. Positive responses occurred in pollinator-excluded flower sensors, neither present ease of PAR integration over numerous points nor minimize the amount of data channels and logger memory consumption. clusters of ‘Black Beauty·, ‘Summit· and especially ‘Sweet Jenny· fi which set 38% fruit that were 92% seedless. However, the fruit size of In this study, we test a ber-optic-based PAR integration system on red these pollinator-excluded cultivars fruit size was reduced significantly. maple crowns. Validation and calibration was achieved by comparing fi In 2002, the responses of these same three cultivars to insect pollinated measurements of ber optic PAR to an orthogonal grid of PAR line vs. insect pollinator-excluded treatments, in conjunction with growth sensors and several quantum sensors positioned at the median of crown layers. Depending upon the positioning of optical fibers and the amount regulators (20 mg·L–1 GA applied pre-bloom alone, or followed by 12 3 of fibers terminated at a PAR sensor, individual leaf, canopy layer, mg·L–1 CPPU applied at 70-80% bloom), were evaluated. Fruit-set in and/or whole-plant light interception can be determined. Integration the insect pollinator-excluded treatments in conjunction with the use of of the quantity of light over numerous points in as little or as large an either growth regulator treatment was greater than in the non-excluded area as necessary is not restricted by geometric shapes and therefore, treatments and was greatest with ·Sweet Jenny·. The highest percentage drastically reduces the number of PAR sensors required. Overall, this of seedless fruit (66%) occurred with ‘Black Beauty·. However fruit study demonstrates that the fiber-optic-based system can be used to size was again smaller with all cultivars where insect pollinators were measure PAR in the canopy of a woody perennial. In addition, the excluded. In another 2002 study involving the self-fertile cultivar ‘Fry use of fiber optics has the added advantage of being cost efficient and Seedless·, GA (20 mg·L–1) was applied alone at pre-bloom; and CPPU 3 minute in comparison to the bulk of a typical quantum sensor. The (either 12 or 24 mg·L–1) was applied alone at 70-80% bloom, or at these end product is potentially a more accurate, less expensive method to same timings in conjunction with a pre-bloom application of GA (20 3 integrate PAR through plant canopies. Lastly, the success shows that mg·L–1). Results showed that these combinations of GA and CPPU 3 the instrumentation and methodology used in sampling and integrating increased fruit set by greater than 100% and fruit size by up to 40% PAR can be improved considerably. over that observed in the untreated control. These results suggest that

combinations of the growth regulators GA3 and CPPU may be useful for increasing fruit set in muscadine grapes and for developing seedless (68) Effect of Intermittent Dim Light on Quality of Cab- fruit. Further work is required to elucidate the effects of cultivars, use bage Plug Seedlings during Low-temperature Storage rates and application timing. Fumio Sato*, Hisao Higashio, Atsuko Uragami, Tokuda Shinichi, Tsuguo Kanno (12) Ripening Promotion of Satsuma Mandarin (Citrus Leaf and Root Vegetables, National Institute of Vegetable and Tea unshiu Marc.) as Influenced by Lysophosphatidic Acid Science, Kannondai 3-1-1, Tsukuba, 305-8666, Japan (Lpa), Lysophos-Phatidylethanolamine (Lpe) We investigated the effect of intermittent dim light on quality Chung-Kil Kang*1, Jong-Hoon Kang2, Guk-Hoon Chung3, of cabbage (Brassica oleracea L. cv. Kinkei) plug seedlings during Jiwan Paul Palta4 low-temperature storage. Seedlings were stored at 10 °C under either 2 1 1Dept. Of Crop Protection, Niast, Rda, 249 Seodundong, Suwon, 441- intermittent dim lighting (1.7 7.6 µmol·m ·s of photosynthetic photon 707, Republic of Korea, 2citrus Tec. Service Dept., Jeju-Do Ar&Es, flux density with 1 h-light: 23 h-dark cycle) or complete darkness, for 313-80 Yeondong, Jeju, 690-813, Republic of Korea, 3-, Doosan Cor- the period of either 3, 6 or 9 weeks. The seedlings stored in darkness poration, Doosan Corporation, Yongin, 449-795, Republic of Korea, 4 elongated succulently due to etiolation, causing a significant deterioration Chief Technology Officer, Nutra-Park Inc., 3225 Deming Way Suite in seedling quality. The intermittent dim lighting suppressed etiolation, 140, Middletone, Wi, 53562 and mitigated dry matter loss of seedlings. All the seedlings stored under the intermittent dim lighting for up to 9 weeks survived poststorage field This experiment evaluated the ripening promotion of Satsuma man- condition, while a half of the seedlings stored in darkness died after being darin (Citrus unshiu Marc.) as influenced by LPA and LPE. Natural stored for 6 weeks. Head weight at harvest was greater in the seedlings lipids, LPA and LPE, derived from soy lecithin were used. Both LPE stored under the intermittent dim lighting than in those stored in darkness. and LPA decreased acidity in the fruit extract. Although there was no effect on the soluble solids, the application of these lipids, increased the sugar-acid ratio. LPA at 200 mg·L–1 stimulated fruit color development (69) Production of Intermountain West Native Perennial by 46.5% as compared with control. In this regard, LPA was more ef- Wildflowers Using Pot-in-Pot Production fective than LPE. When treated with LPA at 200 mg·L–1, the degree of Roger Kjelgren*, Amy Croft, Teresa Cerny, Kelly Kopp ripening stimulation was higher in fruit stalks than in stylar end. Among Plants, Soils, and Biomet, Utah State University, 4820 Old Main Hill, the tested tree positions, the most effective ripening stimulation was Utah State University, Logan, UT, 84322 found in lower, followed by center, and upper side of the tree. LPA was more effective at inner than the outer side of trees. It appears, that The Intermountain West has a diversity of drought-adapted herba-

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ceous perennial species with potential for use in low water landscapes. (72) Effect of Digging Date and Cold Storage on Flowering This study investigated production of native herbaceous perennials of Containerized Roses using a pot-in-pot production system with two growing media under Ursula K. Schuch1, H. Brent Pemberton*2 drip or sprinkler irrigation treatments. Fifteen perennial species were 1 planted in 4-liter containers using either a commercial, high cost, pot- Plant Sciences, University of Arizona, Forbes Bldg. Rm. 303, Tucson, 2 ting mix or a locally constructed, low cost medium, and then installed AZ, 85721, Agricultural Research and Extension Center, Texas A&M in same-sized socket pots. Plants were placed either under point source University, P.O. Box 200, Overton, TX, 75684 drip irrigation or an overhead sprinkler system. Plant height and width Forcing dormant bare root containerized roses (Rosasp.) into bloom and a plant quality rating were determined weekly. The experiment was for spring sales is an expanding market. Each year, several million plants repeated over two growing seasons. There were no significant differences are dug bare root from production fields in Arizona and shipped to Texas between irrigation treatments either year, but the locally constructed where they are forced for the national market. Forcers have observed media had sufficiently higher soil salinity levels and plant growth was variable quality and time to flowering of different cultivars based on affected. Species from more arid, lower elevation habitats were less the time of digging. The objectives of this study were to determine the affected by soil salinity levels than species from more mesic habitats. In effect of plant quality and flowering performance in response to time 2001, plants in the commercial media reached a marketable size in four of digging and cold storage. Different cultivars of bare root roses were weeks, but were left in the ground past this point and declined rapidly obtained from commercial growers in the Phoenix, Arizona area in fall in quality. In 2002, plants reaching marketable quality after four weeks of 2001 and 2002. Roses were dug at three dates from early November were immediately harvested and replaced with a new crop such that to mid December and were kept for 0, 2, 4, or 6 weeks in cold storage we achieved three production cycles. Pot-in-pot production of native (1 °C) for most digging dates. Roses were potted in 2-gal. containers herbaceous perennials has great economic potential in the Intermountain and forced in plastic hoop houses in Tucson, Arizona and Overton, West by increasing the seasonal plant yield for a given area. Texas. A two- to four-week period of cold storage reduced the number of days from planting to first leaf and anthesis by one third up to half of the time for several cultivars compared to plants that were dug early in (70) Preemergence Weed Control in Container-grown November and not placed in cold storage. Later digging dates or two to Herbaceous Perennials and Woody Plants four weeks of cold storage of plants dug in early November increased James Klett*1, David Staats1, Matt Rogoyski2 the number of flowers. Numbers of flowers varied by cultivar; ‘Sonia· 1Department of Horticulture and Landscape Architecture, Colorado and ‘Don Juan·produced the greatest numbers, and ‘Mr. Lincoln·pro- State University, Campus Delivery 1173, Fort Collins, CO, 80523, duced the least amount. The number of blind shoots, dieback percentage 2Department of Horticulture and Landscape Architecture, Colorado and performance were affected by an interaction between cultivar and State University, 3168 B1/2 Road, Grand Junction, CO, 81503 treatments. Starch content of shoots was rated visually after staining During the 2002 season, preemergence herbicides were applied cross sections with lugol solution at the time of planting. Generally, to container grown herbaceous perennials and woody plants and starch ratings increased the later the digging date and decreased with evaluated for weed control, phytotoxicity, and effect on plant growth. increasing time in cold storage. No correlation between starch rating fl The herbicides and rates were: Flumioxazin (Broadstar) 0.25 and 0.5 and owering or overall plant performance was found. In conclusion, lbs ai/A; Isoxaben (Gallery) 1 and 2 lb ai/A; Prodiamine (Barricade) it appears that many rose cultivars destined for forcing in containers fi 0.65 and 1.3 lbs ai/A; Pendimethalin (Scotts Ornamental Weedgrass will bene t from two to four weeks of cold storage to shorten the time fl fl fi Control) 2 and 4 lbs ai/A; and Trifluralin (Treflan) 4 and 8 lbs ai/A. to owering and increase the number of owers. This bene t is great- Herbicides were applied to Artemisia lactifl ora ‘Guizho·, Origanum est for plants dug in early fall, starting in November. This work was libanoticum, Salvia daghestanica, and Scutellaria resinosa. Ninety- supported by commercial producers in Texas and Arizona. five percent of all plant and herbicide combinations did not result in any significant decline in plant growth due to phytotoxicity although (73) Photosynthetic Plasticity of Goldenrain Tree in Re- treatments with Gallery (both rates) resulted in smaller plants when sponse to Varying Light Levels used with Salvia daghestanica. Herbicides provided between 60% and Michael Dosmann*, Thomas Whitlow, Nina Bassuk 100% weed control. Department of Horticulture, Cornell University, 20 Plant Science Building, Ithaca, NY, 14853 (71) Resistance in Crape Myrtles (Lagerstroemia Spp.) to Goldenrain tree (Koelreuteria paniculata Laxm.) is an ornamental Feeding by the Flea Beetle (Altica Litigate) whose natural distribution in China extends from Sichuan eastward to Raul I. Cabrera*1, James A. Reinert2, Cynthia McKenney1 Liaoning, occurring on rocky slopes, open valleys and disturbed habi- 1Horticultural Sciences, Texas A&M University, 17360 Coit Road, tats. Disjunct populations have also been found on coastal dunes of the Dallas, TX, 75252, 2Entomology, Texas A&M University, 17360 Coit Korean Peninsula and Honshu, Japan. This species appears to maintain Road, Dallas, TX, 75252 fitness across a range of limitations (drought, salinity, salt spray), yet it The woody ornamental crape myrtle (Lagerstroemia spp.) is a most is unknown if this is due to phenotypic plasticity or ecotypic adaptation. popularflowering shrub/small tree due to its colorful and lengthy summer The goal of this greenhouse study was to assess the photosynthetic shade flowering and a relatively low landscape maintenance that includes an acclimation of wild-collected 2-year-old goldenrain trees, because such almost pest-free nature. Altica litigate, a metallic blue-green flea beetle plasticity often affects successional status and competitive ability. Leaf that develops high populations on several species of native wildflower emergence and development were hastened in plants grown under the primroses (Oenothera spp.), can severely damage young crape myrtle high light treatment, compared to those exposed to 25% and 10% of plants in container production. In a field (open nursery) study, container- full PPFD. Gas exchange measurements indicate that light compen- ized liners of eleven cultivars of crape myrtles, representing two species sation point, dark respiration, net photosynthetic rate and quantum (L. indica and L. fauriei) and their interspecific hybrids were exposed yield varied by environment, suggesting a degree of photosynthetic to high populations of flea beetles to observe their feeding choice and plasticity in this species. damage. In laboratory experiments young leaves from these crape myrtle cultivars were used to bioassay the flea beetle adults in a no-choice feed- (74) Technical Information Requirements for Hispanic ing study. Cultivars of L. indica were the most susceptible to have severe Nursery Employees—Survey Results from Oregon and damage and defoliation by flea beetles, while a remarkable resistance Ohio was found in L. fauriei cultivars and most of its interspecific hybrids. Hannah Mathers*

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Horticulture and Crop Science, Ohio State University, 2001 Fyffe CT, greenhouse produced with day/night temperature of 25 °C/20 °C (77 FRIDAY pm Columbus, OH, 43210-1096 °F/68 °F) and supplemental lighting (200 µmol·m–2·s–1 at canopy top) Approximately 90% of the Oregon and 60% of the Ohio nursery to maintain 17 hour day length. Plants were grown in 5-quart contain- industry workforces are composed of Hispanic employees. Many of ers in southern pine bark substrate on greenhouse irrigation with 110 these employees understand little English and Spanish is their primary ppm fertilizer at each watering. Initial pruning treatments were done language. In Oregon and Ohio 375 and 250 surveys, respectively were 42 days after sticking cuttings and secondary pruning treatments 60 distributed to Spanish-speaking nursery employees. In Oregon 193 and days after sticking cuttings. For the passion flower cultivars tested, in Ohio 127 were completed. The purpose of these surveys was to deter- none of these pruning treatments increased the number of shoots or mine the backgrounds, experience level and work activities of nursery flowers. ‘Lady Margaret· passionflower pruned once produced 65% workers, their technical information interests, and what resources are less flowers compared to non-pruned plants and those pruned twice available to these workers. The survey response came from 3 sources: produced 89% less flowers. ‘Amethyst· pruned once produced 67% interviews at training programs, on-farm visits, and mailed surveys in less flowers as compared to non-pruned plants and those pruned twice a newsletter format. The survey targeted crew leaders, forepersons and produced 88% less flowers. Both cultivars showed delayed flowering of section supervisors, such as propagation area supervisors. Ninety-five approximately three weeks when pruned once and approximately four and 90% of Ohio surveyed employees indicated that plant identification weeks when pruned twice. For both cultivars tested, pruning resulted and weed control, respectively were technical topics of interest. This in fewer shoots, fewer flowers, and delayed flowering. was significantly different from the survey results in Oregon: 81% chose insect control, 77% weed control, 66% disease control as leading topics 5:30 pm–6:30 pm POSTER SESSION 9 Ballroom A of interest; plant identification rated only 55%. Ninety-three percent of (Location numbers for the posters within the Ohio and 97% of Oregon newsletter readers wanted to continue to receive Poster Viewing Area are in parenthesis) future issues. This finding was consistent with responses from nursery visits and training programs in the two states where respondents indicated Vegetable Crops Management—Preharvest Factors/ their positive reception to receiving technical information in Spanish. Produce Quality

(75) Crabapple Growth and Root Zone Temperatures in (415) The Effect of Root Zone Temperature on Growth Field, Container, and Pot-in-Pot Production Systems and Flavor Potential in Short-Day Onion Catherine Neal* Timothy Coolong*, William Randle Plant Biology, Univ. of New Hampshire, 113 Spaulding Hall 38 Col- Horticulture, University of Georgia, 1111 Miller Plant Sciences, lege Rd, Durham, NH, 03824 Athens, GA, 30602 Pot-in-pot production systems were developed in the South for It has been suggested that water regime and mulching may have moderation of excessive summer media temperatures and have reduced an influence on onion flavor. Because increasing irrigation and using production time of some species by as much as twenty percent compared mulches have been reported to lead to decreases in soil temperatures, to standard container production. The objectives of this research were it was our objective to determine if changes in root zone-temperature to determine whether winter temperature buffering in the pot-in-pot (RZT) could influence onion flavor potential. To test the effects of RZT system is sufficient to prevent root loss in a zone 5 climate, and whether on flavor potential, the roots of ‘Granex 33· onions were subjected to plant growth could be enhanced compared to field or container grown three different temperatures during growth. After 12 weeks of grow- ing at 21 °C, in growth chambers, onion plants were grown with RZT plants. Whips of Malus ‘Donald Wyman· were planted in 22-L pots in a randomized complete block experiment in June, 2001 and grown to setpoints of 12 (±3.0), 21 (±0.6), and 34 (± 0.7) °C, with constant shoot saleable size in two seasons. Growing systems were field, container, temperatures of 21 °C until maturity. Plants were harvested, and bulb pot-in-pot, bag-in-pot and the Above Ground System. First year growth fresh weight (FW), total bulb sulfur (S), pungency, and flavor precur- was greater in all the container systems than in the ground, but by the sor concentrations were obtained. As expected, bulb FW responded middle of the second season the field-grown trees had caught up in quadratically to RZT, increasing from 12 to 21 °C, and then falling as caliper and shoot growth. Root dry weight and total plant dry weight RZT was increased to 34 °C. Bulb total S and total pyruvic acid content, were greatest in pot-in-pot and Above Ground System treatments at the a gross measure of bulb gross flavor intensity, responded quadratically end of the experiment. Monitoring winter soil and media temperatures to RZT, similar to bulb FW, though changes were of a lesser magnitude. showed that pot-in-pot media temperatures were highly correlated with Despite significant changes in bulb S accumulation and gross flavor surrounding soil temperatures, whereas media in containers overwintered intensity, changes in the individual flavor precursors, methyl cysteine in an unheated poly house experienced greater temperature extremes. sulfoxide, 1-propenyl cysteine sulfoxide, and propyl cysteine sulfoxide were minor and not significant. This would suggest that although RZT may have an affect on the overall growth and development in onion, as (76) Pruning of Passiflora‘Lady Margaret·and ‘Amethyst· indicated by the changes in bulb FW, flavor development in the bulb Reduces Shoot Number and Delays Flowering is little influenced by changes in RZT. Stephen Berberich*1, Robert Geneve2, Mark Williams1 1Horticulture, University of Kentucky, N-318 Ag. Sci. North, Lexington, (416) Effect of Prohexidione-Ca and Mepiquat Chloride on KY, 40546-0091, 2Horticulture, University of Kentucky, N-318 Ag. Stolon Production and Yield of Florida-grown Strawberry Sci. North, Lexington, KY, 4056-0091 (Fragraria ×ananassa Duch.) Two passionflower cultivars (Passifl ora ‘Lady Margaret·and ‘Am- John Duval* ethyst·) were evaluated for their flowering response following various Horticultural Sciences, University of Florida, 13138 Lewis Gallagher pruning treatments. Since passionflower plants have the potential to set Rd., Dover, FL, 33527 a flower at each node, the objective of this study was to evaluate the flowering response following treatments to increase lateral branching. Removal of stolons from strawberry plants in Florida·s annual win- Between July 26, 2002 and November 6, 2002 six pruning treatments ter production system incurs significant costs to growers. Mepiquat were tested to determine if branching and flowering capability of these chloride (Ponnax) and prohexidione calcium (Apogee) were evaluated cultivars could be improved compared to plants with no pruning: (1) for the ability to reduce stolon production of strawberries grown under prune the main shoot at the third node, (2) sixth node, (3) ninth node, annual production techniques. Two rates of mepiquat chloride (170.6 (4) third node with all resulting shoots pruned at third node, and (5) and 273.5 g/ha a.i.) and two rates of prohexidione calcium (113.8 and sixth node with all resulting shoots pruned at the sixth node. Plants were 227.6 g/ha a.i.) were applied three times at two week intervals beginning

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4 weeks after establishment. Significant control of stolon production (419) Effect of Tricontanol and Bita-sterol Based Growth was achieved with both rates of prohexidione calcium compared to Regulator ‘Vipul· on Growth, Yield and Quality of mepiquat chloride and untreated controls. However, significant reduc- Tomato tions in yields were associated with prohexidione calcium. Application Jagroop Singh* of mepiquat chloride at 273.5 g ai/ha increased fruit yield during the month of January above all other treatments. Punjab Agriculture University, H. No. 23 G Sarabha Nagar, Opposite PAU Gate-2, Ludhiana, 143203, India (417) Single Centered and Super Colossal Bulbs from An investigation on the effect of tricontanol and Bita-sterol based growth regulator 'Vipul' on growth, yield and quality of tomato was Yellow Onion Cultivars conducted at PAU, Ludhiana during the year 1998-99 and 1999-2000. Clinton Shock*, Erik Feibert, Lamont Saunders Tomato cv. Punjab Chhuhara was given six different treatments. The Malheur Experiment Station, Oregon State University, 595 Onion spring and the autumn crops was sprayed with four ‘Vipul·@ 1 mL/L Ave., Ontario, OR, 97914 (3 sprays), 1 mL/L (4 sprays), 0.5 mL/L (4 sprays), and 0.5 mL/L (5 Onion (Allium cepa L.) cultivars for commercial production in east- sprays ) and two water sprays. Growth, yield and quality contributing ern Oregon and southwestern Idaho are evaluated annually in replicated parameters were positively affected by the various treatments of ‘Vipul· yield trials conducted at the Malheur Experiment Station, Oregon State but its application @ 0. mL/L five times significantly increased the height University, Ontario, OR. Characteristics evaluated include bulb yield, and number of branches. It lead to an average yield record of 374.44 market grade, and single-centers. Total marketable yield out of storage and 236.28 q/ha, respectively during autumn and spring season, though in January ranged from 72-134 Mg/ha (643 to 1196 cwt/acre) in 2000, the quality of the fruit¡s with application of ‘Vipul· was not affected. from 60 to 110 Mg/ha (538 to 980 cwt/acre) in 2001, and from 65 to 125 Mg/ha (583 to 1119 cwt/acre) in 2002. Super colossal bulbs must (420) Enhancing Bell Peppers and Tomatoes Yield with be larger than 10.8 cm (4¼ inches) in diameter and are marketed with Myconate a count of 28-36 bulbs per 23 kg (50 lb.). The percentage of bulbs that Mathieu Ngouajio*1, Jeremy Ernest2, Heather Johnson3, were super colossal averaged 26%, 14%, and 10% in 2000, 2001, and 3 4 2002, respectively. The occurrence of single-centered bulbs was largely Taylor Reid , William Chase determined by cultivar. The percentage of bulbs of a cultivar with only one 1Horticulture, Michigan State University, 428 Plant and Soil Sciences growing point or “bullet” single centers, ranged from 1% to 57% in 2000, Building, East Lansing, Michigan, 48824, 2Horticulture, Michigan from 7% to 70% in 2001, and from 1% to 74% in 2002. The percentages State University, 438 Plant and Soil Sciences Building, East Lansing, of bulbs functionally single-centered for processing uses were higher. Michigan, 48824, 3LLC, VamTech, 3186 Pine Tree Rd, Unit D, Lansing, Michigan, 48911, 4Horticulture, Michigan State University, 288 Plant and Soil Sciences Building, East Lansing, Michigan, 48824 (418) Effect of Clove Orientation on Garlic Bulb Yield in Central Washington Myconate (4·-methoxy, 7-hydroxy isoflavone) is an isoflavonoid isolated from roots of clover plants. Research reports indicate that My- 1 2 3 Erik Sorensen* , Gary Pelter , Roy Vandenburgh , conate can stimulate hyphal growth and root colonization of vesicular Richard Hannan4 arbuscular mycorrhizae (VAM). Under field conditions, improved VAM 1Cooperative Extension, Washington State Univ., 1016 N 4th Avenue, colonization often results in more efficient nutrient uptake and improved Pasco, WA 99301, 2Cooperative Extension, Washington State Univ., crop yield. Our objective was to study the effect of Myconate on growth PO Box 37, Ephrata, WA 98823, 3Cooperative Extension, Washington and yield of bell peppers and tomatoes under Michigan growing condi- State Univ., 128 N 2nd Street, Yakima, WA 98901, 4USDA–ARS, 59 tions. Field studies were conducted in summer 2002 at Michigan State Johnson Hall, Washington State Univ., Pullman, WA 99164 University Horticultural Research Center, East Lansing, Michigan on a In a three-year study, two garlic cultivars were grown to evaluate the sandy clay loam soil. The experiment was a factorial of fertility level effect of clove orientation at planting on subsequent growth and yield. and Myconate rate in a randomized complete block design with four Four treatments were used: cloves planted upright, sideways, inverted, replications. The two fertility levels included 1) low P level and 2) or random. The cultivars selected for this study were ‘California Late· high P level. The Low P treatment received 450 kg/ha of 20N–20P–0K and ‘Korean Six Piece·. The first plants to emerge in the spring were and the high P treatment received 450 kg/ha of 20N–20P–20K prior to those in the plots where ‘California Late·had been planted upright. The transplanting the crops. Initial soil analyses showed 58 and 281 kg/ha plots with the inverted cloves were the last to emerge. With ‘Korean for P and K, respectively. Myconaterates were 0, 62, and 125g/ha. Plant Six Piece·, the inverted and sideways treatments were the slowest to biomass was measured during the season and marketable fruit yield was emerge. The total weight per plot was dramatically decreased with both measured at harvest. Soil fertility level affected plant growth and yield. cultivars in the plots with the inverted planting of cloves. The effect of All treatments with additional P application had plant biomass and fruit inverted planting was greatest with ‘Korean Six Piece·. Planting bulbs yield greater than treatments where P was not added. Tomato yield was inverted reduced total bulb weight by more than 53% with ‘Korean Six significantly increased with Myconate application. In treatments with Piece· and by 37% with ‘California Late·. Among the treatments, the no additional P application, marketable yield was 39.4, 51.0, and 51.2 upright planting had the highest total bulb weight per plot. The inverted tons/ha, for 0, 62, and 125 g/ha Myconate, respectively. Increasing the treatment had the fewest bulbs per plot with both cultivars. The percent rate from 62 to 125 g/ha had little effect on yield. Similar results were reduction in average number of bulbs per plot was nearly 25% with obtained with tomato fruit number. Yield of peppers was generally ‘California Late· and more than 38% with ‘Korean Six Piece·. The high in the Myconatetreatments compared with the control. However, inverted treatment had a lower average bulb weight than the upright, there was more variability in the response compared to tomato. These sideways, or random treatments with both ‘California Late·and ‘Korean results suggest that Myconate could be used to improve tomato and Six Piece·. The bulbs produced in the plots where cloves were planted bell pepper growth, especially under low soil P levels. upside down were typically misshapen. It was also difficult to harvest plants in the inverted plots without breaking the bulbs from the tops. (421) Onion Translucent Scale Resulting from Brief In small-scale operations where garlic is planted by hand, the extra Heating or Freezing time and cost involved in planting bulbs upright may be justified when Clinton Shock*, Erik Feibert, Lamont Saunders large, high quality bulbs are desired. Planting cloves at random most likely results in acceptable yields, but planting upside down should Malheur Experiment Station, Oregon State University, 595 Onion be avoided. Different cultivars may respond to clove orientation to a Ave., Ontario, OR, 97914 greater or lesser degree. Onion (Allium cepaL.) translucent scale is a physiological disorder in

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which the bulb scales or rings acquire a translucent or watery appearance. Dept. of Horticulture, University of Missouri, 1-87 Agr. Building,

Causes of translucent scale are only partially known. Previous research Columbia, MO, 65211 FRIDAY has shown that prolonged field curing and artificial drying increase the High tunnels are unheated, manually vented, passive solar green- proportion of bulbs with translucent scale. We studied the influence of houses that are used to extend the traditional growing season of many brief heating or freezing on translucent scale development in yellow horticulture crops. The objectives of this research were to 1)investigate sweet Spanish onion. Bulbs from the cultivars ‘Ranchero·in 2001 and the effects of high tunnels on yield performance of several tomato ‘Vaquero· in 2002 were harvested from both one furrow-irrigated and cultivars relative to the open field; 2)examine the effects of rowcovers, from one drip-irrigated field each year. Bulbs were submitted to heat clear, black and IRT (infrared transmitting) plastic mulches on extended treatments (27, 32, 38, 43, and 49 °C) in a forced air oven for 20 hours. season tomato production; and 3) determine the optimum planting date Onions were also submitted to <–1 °C for 20 hours. The incidence for maximum early yield of determinate tomatoes. Research was con- of translucent scale was relatively low for all the heated treatments ducted at the University of Missouri in Columbia, Missouri using eight except the 49 °C treatment. Ranchero and Vaquero bulbs heated to research high tunnels. Temperature (soil and air), light and humidity 49 °C showed 44.9% and 31.8% translucent scales, respectively. These were measured through the growing season. Tomatoes grown within translucent scales were deep in the bulb and were persistent during a high tunnel had significantly earlier yield and a greater percentage storage. Freezing of Ranchero led to 57.5% bulbs with translucent of marketable fruit relative to field-produced tomatoes. High tunnels scales, but Vaquero (0%) was not subject to the same injury. After three increased the average daily temperature by approximately 7C. Tomatoes months storage following brief freezing, the number of Ranchero bulbs grown on clear plastic mulch within a high tunnel produced significantly with translucent scale had fallen to 7.5%. In 2002 after handling, the earlier yield relative to tomatoes grown on black plastic mulch. The Vaquero bulbs that had been heated to 27, 32, and 38 °C had 12.7 to optimum planting date for maximum early yield of tomatoes within 10.5% translucent scale, but these translucent scales were not observed an unheated high tunnel is mid-March. one, two, and three months later, suggesting that injury during handling alone might cause reversible translucent scale. (430) Intercropping Systems for Tomato Production Within High Tunnels in the Central Midwest (422) Influence of Post-fruit Set Plant Exposure to Low Jay Chism, Lewis Jett* Light Intensity on Growth and Yield of Oriental Melon (Cucumis melo L.) Dept of Horticulture, University of Missouri, 1-87 Agr. Building, Columbia, MO, 65211 Sang Gyu Lee*1, Young Chul Kim2, Hyo Duk Suh3, 4 High tunnels are unheated, passive solar greenhouses that can Chiwon W. Lee extend the traditional growing and harvesting season of many horti- 1Department of Vegetable Culture, National Horticutural Research culture crops. Intercropping of vegetables within high tunnels further Institution, 475 Imok-dong, changan-gu, Suwon, 440-310, Republic of increases the efficiency of this production system. The objective of Korea, 2Vegetable Cultivation Division, National Horticutural Research this research was to examine intercropping of tomatoes with lettuce as Institution, 475 Imok-dong, Changan-gu, Suwon, 440-310, Republic of a technique to extend the harvest season of lettuce while establishing Korea, 3Vegetable cultivation Division, National Horticutural Research early tomatoes. Research was conducted at the University of Missouri Institution, 475 Imok-dong, Changan-gu, Suwon, 440-310, Republic of in Columbia, MO. Tomatoes (cv. ‘Merced·) intercropped with lettuce 4 Korea, Department of Plant Sciences, North Dakota State University, (cv. ‘Red Salad Bowl·) showed no significant reduction in marketable Loftsgard Hall 266F, Fargo, ND, 58105 yield relative to noninterplanted (monoculture) tomatoes. Relative yield The onset of a low-light condition after fruit-set often reduces the totals indicated that intercropping increased the area efficiency by 47% yield and quality of Oriental melons. This study examined changes in relative to monoculture tomatoes. growth of Oriental melon (Cucumis melo L. var. makuwa Makino) in –2· –1 response to reduced light (100, 200, 400 µmol·m s ) by shading the (431) Development of Substrates for Greenhouse Tomato natural light 10 days after fruit set (6 fruits per plant). Plants exposed Production to low light intensity had significantly smaller leaf areas, shorter roots, 1 1 1 and lower fresh and dry weights as compared to those remained under Marie-Claude Desbiens* , Jean Caron , Suzanne Allaire , natural light. However, plant height and stem diameter were unaffected Claudine Ménard2, Martine Dorais2 by low light conditions. The rate of photosynthesis and total chloro- 1département Des Sols Et Génie Agroalimentaire, Université Laval, phyll content decreased with reduced light intensity. Root activity, as Pavillon Comtois, Sainte-foy, Qc, G1k 7p4, Canada, 2Agriculture determined by formazan test, was higher in plants grown under natural Et Agroalimentaire Canada, Centre De Recherche En Horticulture, light than in those exposed to low light. There was no significant dif- Université Laval, Sainte-foy, Qc, G1k 7p4, Canada ference in root activity among plants grown under the three different Environmental concerns relative to pollution associated with green- light intensities. Leaves of the plants exposed to low light intensity house production and the need to give plus value to industrial waste had only 30% to 50% of trans-zeatin levels compared to those grown products justify the interest in developing new horticultural substrates. in natural light. Development of leaf chlorosis and incidence of fruit Indeed, rockwool presents recycling problems and its replacement by drop increased as light intensity reduced. Total fruit yield was severely more environmental friendly substrates is a worldwide target. In a prelim- reduced by lowered light intensity. Percent marketable fruits from total inary experiment, pine, cedar and spruce sawdust substrates and brown harvests were 0, 3, 10, and 81%, respectively, for plants grown under sphagnum peat alone and with fir/spruce composted bark were compared –2· –1 100, 200, 400 µmol·m s , and natural light. during a six month incubation in laboratory to optimise aeration, water retention and quantify immobilization and microbial activity. Results 5:30 pm–6:30 pm POSTER SESSION 10 Ballroom A indicated that peat substrates were asphixiant and that adding composted bark did not significantly improve aeration. Pine sawdust presented poor (Location numbers for the posters within the water retention and stability compared with cedar and spruce sawdust. Poster Viewing Area are in parenthesis) Important nitrate immobilization occurred in sawdust based substrates. Vegetable Crops Management—Cropping Systems As a result, three new approaches were compared for a greenhouse tomato experiment: container geometry was modified to enhance peat (429) Tomato Cropping Systems for High Tunnels in the areation; rockwool was added to spruce sawdust in order to improve Central Midwest water retention and N fertilizer was increased for spruce sawdust. Tomato response to the enhanced aeration was negligeable. Spruce sawdust Lewis Jett*, Andrew Read consists of a valuable alternative to rockwool but will require significant

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water saving strategies. Immobilization results will also be discussed. (434) Relationships Among Traits Affecting the Quality of Cabbage (Brassica oleracea L. Capitata Group) Heads fl (432) Cultivation of Baby Greens and Baby Lettuce in Alaska are In uenced by Ontogeny Roseann Leiner* Theodore J.K. Radovich*, Matthew D. Kleinhenz, Nathaniel J. Honeck Palmer Research and Extension Center, University of Alaska Fairbanks AFES, 533 E Fireweed Ave., Palmer, AK, 99645 Horticulture and Crop Science, The Ohio State University, Ohio Ag- ricultural Research and Development Center, 1680 Madison Avenue, Alaska is at the end of the supply line for fresh vegetables. Fortu- Wooster, Ohio, 44691 nately, the summer season is suited for local production of cool season vegetables, including crisphead lettuce and cabbage. New crop oppor- Cabbage head quality is rated according to absolute values of char- tunities exist for production of baby lettuce and baby greens, which acteristics such as head size, shape and density. Identifying consistent fi are sold at farm markets and to gourmet restaurants. Baby greens are relationships among these traits is also of practical and scienti c value also suggested for home gardens and cultivation in rural communities as researchers seek to better understand cabbage head development and where transportation costs limit the availability of salad vegetables. crop managers explore ways to implement quality-oriented management Field plots were planted in 2000, 2001, and 2002 to evaluate the strategies. Some evidence for stable relationships among key traits in cultivation techniques and cultivars of baby greens and baby lettuce. market-ready heads is available, but the existence of similar relation- In 2000, there were two plantings of baby lettuce (Lactuca sativa, ships at earlier stages in head formation has not been tested. Therefore, 31 cultivars) and one planting of baby greens (Brassica species - 12 three relationships (head weight vs. mean diameter, polar diameter vs. cultivars ). In 2001, there were two plantings of baby greens (Brassica equatorial diameter, and head volume vs. core volume) were studied fi species - 14 cultivars) and one planting of baby lettuce (9 cultivars). In at ve stages of development over two years in Ohio. A total of three 2002, there were two plantings of five types: the Asian green, mizuna fresh market and processing cultivars were grown in 2001 and 2002 at (Brassica rapa cv. Kyona), red giant mustard (Brassica juncea) and The Ohio State University Ohio Agricultural and Development Center kale (Brassica oleracea cv. Bona), red Russian kale (Brassica napus), (OARDC) in Wooster, OH. Seedlings in the 2–4 true leaf stage were and arugula (Eruca versicaria), at three fertility levels: none added, low, planted in mid-June of both years in a RCB design with four replica- and high. Twenty one to 40 days after planting, individual leaves were tions. Five harvests of 10–20 heads per plot were completed at 7-d cut, washed, weighed, and samples were dried. Mizuna was harvested intervals, beginning 35 d before the estimated market maturity date first, with a range of 0.9 to 2.0 average grams per plant in the first plant- for each cultivar. Harvest number and cultivar affected all head traits ing. Bona Kale was harvested last, with a range of 1.2 to 3.9 average and the rate of change in head traits differed with cultivar. However, grams per plant. The other types had higher weights, with a range of clear trends were observed for all three cultivars in both years. Den- fi 1.6 to 6.8 average grams per plant in the first planting. The difference sity increased 8% to 25% in ve weeks, indicating that gains in head in yield between low and high fertility rate was small, suggesting that weight exceeded gains in head size during the same period. Also, a 2 low fertilizer rates are sufficient because the time to harvest is short. consistent relationship, described by a power equation(R >0.90), was The color and leaf shape of baby lettuce was appealing to the eye, but found between individual head weight and mean diameter suggesting texture and taste was mild when informally compared to baby Brassica that reliable predictions of head weight based on size are possible over greens. Gentle handling during harvest and washing are necessary to a wider range of crop development than previously reported. Interest- maintain market quality. ingly, head expansion was not uniform in all directions as the ratio of polar to equatorial diameter decreased 7% to 18% from the first to last harvest. Finally, the volume of internal head space occupied by (433) Sweet Potato Cultivars Performances Under the core decreased 30% to 50% over five weeks, reinforcing the idea Different Cultural Practices in Arkansas that stem elongation slows as heads develop and suggesting that the Ehiorobo Izekor*1, James Garner2, Antonio Corely3 percent of usable product for processors may increase as heads mature. fi 1Agriculture, University of Arkansas at Pine Bluff, University of Similar relationships among head traits were found in ve additional Arkansas, 1200 N. University, P.O. Box 4966, Pine Bluff, Arkansas, cultivars planted at the OARDC only in 2002. This characterization 71601, 2Agriculture, University of Arkansas at Pine Bluff, University of relationships among key head traits offers an alternative approach of Arkansas, 1200 N University P.O. Box 4966, Pine Bluff, Arkansas, to the study of factors controlling head maturation. It will also assist 71601, 3Agriculture, University of Arkansas at Pine Bluff, University of in the development of production-based strategies to maximize raw fi Arkansas, 1200 N University P.O. Box 4966, Pine Bluff, Arkansas, 71601 product quality and processing ef ciency. Seven sweet potato [Ipomoea batata (L.) Lam.] cultivars and two advanced breeding lines were tested in 2000 and 2001, at three (435) Field Performance of Edamame (Glycine max) locations in Arkansas, to study storage root yield and market quality Cultivars differences. The effect of N fertilization rates and in-row plant spacings Elsa Sanchez*, Kathleen Kelley on yields and market quality was also examined. In 2001, ‘Beauregard· Pennsylvania State University, Department of Horticulture, 102 Tyson ‘Hernandez·, ‘Jewel·, ‘96-94·and ‘89-110·had total marketable yields Building, State College, Pennsylvania, 16802 of 882, 879, 817, 800 and 714 bu/A respectively. US#1 grade yields from the above cultivars and breeding lines doubled the state average Marketing and producing alternate crops, such as ethnic produce, of 168 bu/A. The 2000 growing season was less productive due to a may offer small-acreage growers an opportunity to develop poten- fi prolonged drought. ‘Porto Rico· produced the lowest yields among tially pro table niche markets. One such crop in Pennsylvania may all cultivars tested (average total yield 345, US#1·S 155, bu/A) at the be edamame (Glycine max), also known as edible or vegetable soy- fi three locations. Yield response to N fertilization rates (20 and 40 lb N bean. An in eld cultivar trial was conducted in 2002 at the Russell E. per acre) and in-row spacings (7, 10 12, and 15 inches) increased the Larson Agricultural Research Center, Rock Springs, PA to assess the number of canners and US#1 grades. US#1 yields at 7 and 10 inches best cultivars for production in PA. The trial contained 9 commercial spacings were 55 and 47 percent higher compared to 12 and 15 inches entries; Early Hakucho, Lucky Lion, Green Legend, Late Giant Black spacings under low N (20 lb/A) fertilization treatments. However, an Seeded, Butterbeans, Envy, Kenko, Butterbaby and Shironomai. Data fl increase in total yields including the jumbo grade was recorded for the collected from the crop included germination rates, days to owering fi fi wider in-row spacings (15 inches) under high (40lb/a) N treatments. and harvest measurements. The nal germination rate for the eld varied fi Discarded culls due to undersized and misshaped roots were significantly signi cantly by cultivar and ranged from 11% for Butterbaby, 14% for higher for 7 inch spacing with high N (40 lb/A). Shironomai to 77% for Envy. Differences were also observed between the cultivars in days to flowering with Envy flowering the earliest, be-

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ginning 48 days after planting. Other cultivars began flowering within The Michigan State University Green Roof Research Program is the next week with the exception of Late Giant Black Seeded, which conducting ongoing studies monitoring a wide range of performance FRIDAY pm began flowering 97 days after planting. Shironomai had the highest factors, environmental benefits, and designs for extensive green roof marketable yield of all cultivars. Other cultivars had statistically similar systems. Green roof research at MSU began in collaboration with marketable yields with the exception of Envy, which had lower yield Ford Motor Company in an attempt to make recommendations on than Butterbaby. Shironomai also had high marketable yields in other the design and implementation of an extensive green roof on a new cultivar trials conducted by other researchers in the US. However, the vehicle assembly plant at the Rouge Manufacturing Facility (Dearborn, germination percentage of Shironomai was unacceptably low. Germi- MI). Preliminary research began with studying substrate composition, nation for this cultivar will be further studied to determine whether plant propagation and establishment, plant species, nutritional require- this is a viable option for PA growers. Until then, better choices are ments, green roof drainage systems, and precipitation runoff quality Butterbeans, Envy and Early Hakucho based on germination percent- and quantity. Eighteen Michigan native herbaceous species and nine ages and marketable yield. species of Sedum were evaluated for rate of establishment, capability to exclude invasive weeds, and temperature and drought tolerances. (436) Heirloom Tomato Cultivar Selections for New Jersey Ongoing and future research at MSU includes additional water quality and quantity of runoff, including studies on various depths of substrate, 1 2 3 Wesley Kline* , Peter Nitzsche , Maureen Scaramella slopes of roofs, and comparisons between conventional flat roofs and 1Agricultural and Resource Management Agents, Rutgers Cooperative extensive green roofs. These experiments are currently being conducted Extension, 291 Morton Ave., Millville, NJ, 08332, 2Agricultural and on 27 simulated roof platforms at MSU. The research site is equipped Resource Management Agents, Rutgers Cooperative Extension, P.O. with Campbell Scientific automated monitoring equipment including Box 900 - Court House, Morristown, NJ, 07963, 3Food Innovation a weather station, temperature sensors installed at various substrate Research and Extension Center, Rutgers Cooperative Extension, 87 depths, and electronic tipping bucket rain gauges installed to measure East Commerce St., Bridgeton, NJ, 08302 rate and volume of precipitation runoff. Greenhouse studies are being Heirloom tomatoes are receiving increased interest among consum- conducted to determine minimally sustainable irrigation requirements ers and growers in New Jersey. However, growers are not sure which for various plant species in differing water retention design combina- cultivars to plant since there are several thousand available. The New tions. Additional research is being conducted to evaluate the green Jersey Tomato Enhancement Project is evaluating heirloom cultivars roof system potential of 40–50 less-common species and cultivars of for their horticultural characteristics and consumer acceptance. One Sedum. In addition to the pilot-scale studies being performed in our hundred and ten cultivars were planted in a randomized complete block test facilities, we are working closely with Ford Motor Company and design with two replications at two locations (north and south) in New commercial green roof system producers to monitor, evaluate, and Jersey. Plant (color, vigor, height, fruit cover, leaf type, and vine size) optimize approaches for advanced extensive green roof systems. and fruit quality (shape, external color, firmness, stem scar, blossom scar, jelly color and core size) characteristics were evaluated during (315) Green Roof Slope, Substrate Depth, and Vegetation the growing season. At the southern location, fruits were harvested Influence Runoff weekly from July 26 to October 8 and graded. For analysis purposes 1 2 3 cultivars were subdivided into cherry, small, medium, large round and Nicholaus VanWoert* , D. Bradley Rowe , Clayton Rugh paste types. Fruit from these trials were also used for taste panels with 1Horticulture, Michigan State Univ., A288 Plant & Soil Science Bldg, consumers, chefs, and supermarket buyers. Based on the horticultural Michigan State Univ., East Lansing, MI, 48824, 2Horticulture, Michigan and taste panel evaluations the cultivars ‘Isis Candy·, ‘Snow White·, State Univ., A212 Plant & Soil Science Bldg., Michigan State Univ., ‘Red Pear·, and ‘Yellow Pear· (cherry types); ‘Borgo Cellano·, Juane East Lansing, MI, 48824, 3Crop And Soil Sciences, Michigan State Flammee·and ‘Garden Peach·(small round); ‘Arkansas Traveler·, ‘Eva Univ., 516 Plant & Soil Science Bldg., Michigan State Univ., East Purple Ball·, Green Zebra·, and ‘Costuloto Genovese·(medium round); Lansing, MI, 48824 ‘Mortgage Lifter·, ‘Box Car Willie·, and ‘Brandywine·(Landis Valley Stormwater runoff is an ever-increasing concern as humans continue Strain) (large round); and ‘Black Plum·, ‘Italian Gold·, and ‘Heidi·(plum to develop land and construct impervious surfaces that can overtax our types) are being recommended to growers for commercial trials. municipal sewer systems. Green roofs provide an opportunity to mitigate this negative impact because of their potential to retain stormwater. 5:30 pm–6:30 pm POSTER SESSION 11 Ballroom A However, scientific research quantifying these characteristics is lim- (Location numbers for the posters within the ited. Therefore, our objective was to quantify the differences in water retention among combinations of various green roof slopes, substrate Poster Viewing Area are in parenthesis) depths, and roof types. Fifteen simulated rooftop platforms measuring Water Utilization and Management 2.4 m × 2.4 m (8 ft × 8 ft) were constructed, each containing substrate and a Xeroflor drainage system consisting of a water holding fleece (314) The Green Roof Research Program at Michigan layer and nylon coils. The growing substrate was composed of 40% State University heat-expanded slate, 40% sand, 15% organic matter, and 5% dolomite. Nicholaus VanWoert*1, Angela Durhman1, D. Bradley Rowe2, Vegetation was a mixture of seven species and cultivars of Sedum. The Clayton Rugh3, Michael Monterusso4, Don Russell5, first study compared slope (2% and 6.5%) and substrate depth (2.5, 4.0, R. Thomas Fernandez6, Jeffrey Andresen7 and 6.0 cm), while the second compared roof treatments (vegetation, substrate only, and gravel ballast). The site was equipped with a weather 1Horticulture, Michigan State Univ., A288 Plant & Soil Science Bldg, station and electronic tipping buckets that recorded the volume and rate Michigan State Univ., East Lansing, MI, 48824, 2Horticulture, Michigan of stormwater runoff from the individual platforms every five minutes State Univ., A212 Plant & Soil Science Bldg., Michigan State Univ., East around the clock. Quantity of rainfall retained in the slope/depth study Lansing, MI, 48824, 3Crop And Soil Sciences, Michigan State Univ., ranged from 93% (2% slope, 4.0 cm substrate) to 86% (6.5% slope, 4.0 516 Plant & Soil Science Bldg., Michigan State Univ., East Lansing, cm substrate). Effect of vegetation was significantly greater as platforms MI, 48824, 4Project Director, Xeroflor America, P.O. Box 24066, Lan- containing 100% vegetation cover retained 90% of the rainfall com- sing, MI, 48909, 5Environmental Quality Office, Ford Motor Company, pared to 66% for substrate without plants and only 35% for a typical Ste. 1400, One Parklane Blvd., Dearborn, MI, 48126, 6Horticulture, commercial roof with gravel ballast. Results indicate that roof slope, Michigan State Univ., A216 Plant & Soil Science Bldg., Michigan State substrate depth, and the presence of vegetation all influence retention. Univ., East Lansing, MI, 48824, 7Geography, Michigan State Univ., One must also consider the intensity and duration of the rainfall as well 417 Natural Science Bldg., East Lansing, MI, 48824 as substrate moisture content immediately prior to the rainfall event.

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(316) Waiver of Ground Water Nitrate Liability for Con- and encourage healthier, more drought tolerant plants. Low water use tainer Plant Producers landscapes composed of drought tolerant species grouped according Thomas H. Yeager*1, Kenneth A. Kuhl2, James R. Spratt2 to their water requirements (hydro-zoning) would help ensure that less water is used. However, for the public to use these plants efficiently, 1 Department of Environmental Horticulture, IFAS, University of they need to distinguish among their levels of drought tolerance. The 2 fi Florida, PO Box 110670, Gainesville, Florida, 32611, Of ce of Agri- objectives of this research were to evaluate the effectiveness of a line cultural Water Policy, Florida Department of Agriculture and Consumer source irrigation system for determining water requirements of herba- Services, Governor·s Square Blvd, Tallahassee, Florida, 32301 ceous perennials and to identify potential low water use plants for arid Florida producers of container-grown nursery plants are eligible to landscapes. The system used a line source irrigation plot with water receive a waiver from the cost of cleaning up wells that contain nitrate levels from spray heads decreasing with increasing distance from the concentrations greater than 10 mg/liter. Chapter 576.045, Florida Stat- center irrigation line. Ten different herbaceous perennial species were utes, established provision for this waiver. The Florida Nurserymen and used with 7 plants per species. The rows of species were randomly Growers Association membership has developed an interim measure placed in four different blocks in the plot layout. Irrigation was run at titled “Interim Measure for Producing Container-grown Plants” that 100% ET one time per week for the plants closest to the line. The water has been adopted by rule under Chapter 576.045, F.S. Container plant applied decreased by approximately 10% for each 0.6 m the plants were producers that implement the management strategies outlined in the positioned away from the center line. Irrigation spray applied at 30 PSI interim measure and keep appropriate records will receive the waiver. was influenced by wind speeds as low as 4 mph. Shoot dry weight of The process of building consensus with regards to interim measure Aquilegia fl avescens, Geranium viscosissimum, Penstemon mexicali content and subsequent education for nursery plant producers will be ‘Red Rocks·, and Echinacea purpureadecreased with decreasing water presented. This information could be used as a model for develop- applications. However, Gaillardia aristata, Sphaeralcea munroana, ing proactive university extension educational programs that involve Oenothera macrocarpa, Calylophus hartweggi, and Eriogonum jamesii regulatory issues. had similar shoot dry weights under all irrigation treatments, suggesting their potential for use in low water landscapes. (317) Educating Large Urban Landscape Water Users Teresa Cerny, Kelly Kopp*, Roger Kjelgren (319) Use of Surfactants for Production of Viburnum with Plants, Soils, and Biometeorology, Utah State University, 4820 Old Cyclic and Non-cyclic Microirrigation Main Hill, Logan, UT, 84322-4820 J.B. Million*, T.H. Yeager, J.E. Barrett Greater than 75% of the population of the Intermountain West is Department of Environmental Horticulture, IFAS, University of Florida, located in urban areas. Water supplies are critical in supporting these PO Box 110670, Gainesville, FL, 32611 populations but supply and demand projections show existing water Container substrates are amended with surfactants to improve wet- sources will be tapped out in several years. Urban landscapes account ting. AquaGro G (0 or 593 g m-3 pre-plant incorporated), AquaGro TDG for 50-75% of the total yearly municipal water use in Utah. Therefore, (0 or 75 g/container top-dressed every 8 weeks), and a combination educating urban landscape water users on ways to conserve water is of both were evaluated for production of Viburnum odoratissium Ker- needed. Utah State University s Center for Water Efficient Landscap- · Gawl. in 50-L containers with a commercial peat-bark-sand substrate. ing spent Summer 2002 developing and presenting a Water Use Spray stake irrigation was applied in either one or two cycles/day with Workshop series for large water users in the highly populated urban volume adjusted periodically to maintain a low (0.2–0.3) leaching frac- areas. The workshops were done at the request of the Utah Division tion (LF). Each surfactant resulted in increased plant shoot dry weight of Water Resources and several other water agencies. These agencies (19% to 28%) compared to plants grown without surfactant. There was also helped to fund the workshops. The series of full day workshops no apparent benefit from applying both surfactants. AquaGro TDG covered irrigation maintenance and scheduling, ornamental and turf resulted in reduced leaching fraction, particularly during the summer management, irrigation auditing, and consisted of a field exercise to and fall and with the one cycle/day irrigation schedule. After 9 months, determine irrigation uniformity. Each participant received a workbook substrate moisture distribution within the container was greater for with the presentations along with catch cups and a soil probe. A writ- AquaGro TDG than AquaGro G; however, root distribution was not ten survey was distributed at the end of each of the workshops and different. Based on these data, plants grown in substrate amended with was collected from each participant before they could receive their surfactant exhibited more growth and less leaching than containers not certificate of completion. Participants, managing an average of 200 amended with surfactant. acres of landscaped areas each, were employed by churches, lawn care companies, water conservancy districts, parks/recreation facilities, and schools in the highly urban areas. All participants either strongly (320) Response of Vinca and Salvia to Reclaimed Water agreed or agreed that the workshops were beneficial, the information J.K. Von Merveldt*, C.A. Larsen, T.H. Yeager, J.E. Barrett was understandable, and that the workbook was a helpful addition to Department of Environmental Horticulture, IFAS, University of Florida, the programs. Responses to the survey indicated that the workshops PO Box 110670, Gainesville, FL, 32611 increased awareness of water conservation practices and have the po- Plugs of Catharanthus roseusandSalvia splendenswere potted with tential for changing behavior in regards to applying more landscape Metro Mix 500 in 2.8-liter containers and fertilized with 9 g/container water conservation practices. of Osmocote (14N–6P–12K) applied to substrate surface. Plants were placed on a greenhouse bench in a randomized complete block ar- (318) Using Line Source Irrigation to Evaluate Potential rangement with factorial combinations of reclaimed water (processed Low Water Use Herbaceous Perennials liquid from municipal sewage treatment facilities) and distilled water Teresa Cerny, Roger Kjelgren* that comprised 0%, 25%, 50%, 75%, or 100% reclaimed water applied as needed. Irrigation with the various percentages of reclaimed water Plants, Soils, and Biometeorology, Utah State University, 4820 Old was applied to the substrate surface (surface placement) or the same Main Hill, Logan, UT, 84322-4820 percentage of reclaimed water was applied to the substrate surface with Water shortages in Utah are forcing the public to evaluate more an additional 50–70 mL of the irrigation water sprayed over foliage of fi ef cient ways to manage our water. Urban landscapes account for 50% plants (surface + overhead placement) for each respective percentage to 75% of the total yearly municipal water use in Utah and much of it of reclaimed water applied to substrate surface. Shoot dry weights of C. is applied in excess of actual plant water needs. Irrigation scheduled roseus were not different after 7 weeks due to irrigation placement and according to landscape plant water needs can reduce excess irrigation increased slightly as the percentage of reclaimed water increased. Root

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dry weights were not different due to percentage of reclaimed water as an excellent fact about the garden center where they shopped at. The FRIDAY pm applied but were larger for the surface + overhead placement (3.3 g) majority of the customers ranked cleanliness of the facility, knowledge- compared to surface placement (3.1 g). S. splendens shoot dry weights able employees, product quality, growing care information, garden center were not different after 8 weeks due to percentage of reclaimed water layout, ease of shopping, price of the product, and efficient check-out as applied or irrigation water placement. Root dry weights were generally good facts. Parking facilities and labeling of plants were ranked as fair smaller for the surface + overhead treatments and root dry weights by most customers. Also, respondents indicated that the garden centers decreased as the percentage of reclaimed water applied increased. were their main source for gardening products such as fertilizers, pot- Substrate electrical conductivity levels after 4 weeks ranged from 0.4 ting soil, mulch, pesticides, etc. Over 80% of the customers assigned dS/m for plants that received 0% reclaimed to 1.6 dS/m for plants that an overall rating of good to the garden center where they shopped. received 100% reclaimed irrigation water. (323) Customer Survey of Plant Purchase Preferences for (321) Yield and Water Use of Hot Peppers Under Three Nursery Stock in Texas Irrigation Regimes Sudeep Vyapari*1, Jacqueline Maisel2 Manuel Palada*, Daniela O'Keefe, Jeanmarie Mitchell 1Department of Environmental Horticulture, University of Florida, Agricultural Experiment Station, University of the Virgin Islands, RR UF/IFAS, 1200 North Park Road, Plant City, FL, 33566, 2Department #2, Box 10,000, Kingshill, VI, 00850, Virgin Islands (U.S.) of Agricultural Sciences, Sam Houston State University, University Field trials were conducted over two seasons to determine the Avenue, Huntsville, TX, 77341 response of hot pepper (Capsicum chinense L.) cultivars to levels of A survey was conducted to determine customer preferences for drip irrigation. Four cultivars (Habanero, Red and Yellow Scotch Bon- nursery stock and factors affecting the purchasing trends in Texas. The net and West Indies Red) were drip irrigated at soil moisture regimes information gathered is important to growers and retailers for creating a maintained at –20, –40, and –60 kPa based on soil tensiometer. The niche in the present market. Mail-in surveys were sent to 800 randomly trial was designed using a split-plot in randomized block design. The selected customers in four major metro areas of Texas (Austin - AUS, drip irrigaiton regimes were the main plots and the cultivars were the Dallas-Fort Worth - DFW, Houston - HOU, and San Antonio -SAN) in subplots. Data on irrigation water use, weight and size of fruits and Spring 2002. Demographic information of the respondents indicated fruit pungency were collected. Results indicated no significant (P > that 50% of the customers were in the age group of 30-55 years, owned 0.05) response to irrigation level in both seasons. Yield of cultivars at a single family home, and shopped at a garden center located within a each irrigation level also did not differ significantly in both seasons, two to five miles radius of their residence. The overall response showed however, in the second season there was a significant (P < 0.05) interac- that 40% of the customers bought their plants at a garden center not tion between irrigation level and cultivar indicating that some cultivars associated with a mass merchandiser (Wal-Mart, Home Depot etc.). responded favorably to increasing irrigation rate while others did not. Mass merchandisers ranked number two in AUS, DFW, and HOU The effect of irrigation regime on pungency was not significant, but and were most popular in SAN. Plant purchases through mail-order cultivars differed significantly in pungency. Water use efficiency was or internet were found less popular among respondents. Annuals were highest at irrigation regime of –60 kPa. This study indicates that increas- the most popular group of plants purchased followed by perennials, ing irrigation rates has no effect on hot pepper yield and, therefore, hot roses, bulbs, shrubs, and vegetables. San Antonio respondents bought peppers can be produced with minimum irrigation. more vegetables when compared with the customers from the other metro areas surveyed. Shrubs were more popular in AUS, DFW, and (322) Factors Influencing Customer Preferences for HOU than SAN. Purchase of trees ranked lower when compared with several other groups of plants. Customers from AUS indicated a higher Nursery Stock Purchases in Texas preference for purchase of roses and bulbs than DFW, HOU, or SAN. 1 2 Sudeep Vyapari* , Jacqueline Maisel The most popular time of plant purchase among respondents was spring 1Department of Environmental Horticulture, University of Florida, followed by fall. An interesting observation between the age groups UF/IFAS, 1200 North Park Road, Plant City, FL, 33566, 2Department and purchasing preferences showed that annuals and perennials were of Agricultural Sciences, Sam Houston State University, University most popular among all the age groups. Overall, 32% of the respondents Avenue, Huntsville, TX, 77341 spent two to four hours per week in gardening activities. DFW data Data gathered from a survey conducted in Spring 2002 represents showed that 25% of the customers spent more than seven hours per customer attitudes and factors influencing the purchases of nursery stock week gardening. In Austin, 60% of the respondents visited a garden in four metro areas of Texas (Austin AUS, Dallas-Fort worth DFW, center seven or more times during a year. Houston HOU, and San Antonio SAN). Mail-in surveys were sent to 800 randomly selected customers in these metro areas. Overall results 6:30 pm–8:00 pm Westin-Narragansett Ballroom showed that customers consider plant prices as the most important fl factor influencing their decision to shop at the garden center of their Welcome Reception & ASHS Endowment Fund Raf e choice. Wide product selection, customer satisfaction, and high product [Advance Registration Required] quality are the next three factors that influenced plant purchases equally among customers. Overall appearance of a garden center and credit Come celebrate our 100th birthday at the opening reception for arrangements were less influential among the factors considered in the the ASHS-2003 Centennial Conference. Meet and greet your col- decision making process. When asked how the customers found out leagues and friends while enjoying some surprise entertainment. In about the garden center where they shopped at, 38% of the respondents addition, this year the ASHS Endowment Fund will be sponsoring found the garden center as they passed by it while driving. Newspaper a raffle with many fabulous prizes. All of the proceeds will benefit and word of mouth were the next popular methods of advertisement the ASHS Endowment Fund, which supports horticulture education while yellow page listings were the least popular method. Over 94% and research through student scholarships and other educational of the customers indicated that they would buy plants with low water tools. RRaffle Tickets are $10.00 each or 3 for $25.00, and win- requirements, and 60% of the respondents indicated that they owned an automatic sprinkler system. On a scale of 1 through 4 (1 = excellent, 2 = ners will be announced during this reception (you do not need to good, 3 = fair, or 4 = poor), 44% of customers ranked display of plants be present to win).

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