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Briana L. Gross, Gayle M. Volk, Christopher M. Richards, Patrick A. Reeves, Adam D. Henk, Philip L. Forsline, Amy Szewc-McFadden, Gennaro Fazio, and C. Thomas Chao

consumer demand for organic produce and heritage apple cultivars. The USDA-ARS National Plant Germplasm System (NPGS) apple collection in Geneva, NY, has key genetic resources that can be used in breeding and research programs to address the threats to

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Charlene M. Grahn, Barbara Hellier, Chris Benedict, and Carol Miles

temperate regions. California and Arizona are the main production areas of leafy green salad crops, producing 96% of all lettuce grown in the United States, with 70% of baby leaf salad crops produced in the Salinas Valley ( City of Salinas EDO, 2013 ; USDA

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Gayle M. Volk and Christopher M. Richards

USDA's National Plant Germplasm System (NPGS) maintains the world's largest living collection of plant genetic resources. The NPGS is tasked with acquiring, preserving, characterizing, and distributing the over 450,000 accessions. Major components

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Milton E. Tignor Jr., Frederick S. Davies, and Wayne B. Sherman

Citrus hybrids USDA 17-11 [Citrus grandis L. × (C. paradisi Macf. `Duncan' × Poncirus trifoliata (L.) Raf. `Gotha Road')] and 119 [(C. paradisi Macf. `Duncan' × P. trifoliata (L.) Raf. `Gotha Road') × C. sinensis (L.) Osb. `Succory'], `Hamlin' orange [C. sinensis (L.) Osb.], and satsuma mandarin (C. unshiu Marc.) were planted March 1993 and 1994. Trees were irrigated and fertilized in an identical manner. In 1993, electrolyte leakage readings were taken monthly using 17-11, 119, and satsuma leaf discs. Leaf killing point (LKP) LT50 averaged from –8 to – 9C by mid-November for all selections. In 1994, leaf discs from 17-11, 119, and `Hamlin' orange were sampled weekly to determine LKP. USDA 119 had the lowest LKP and acclimated the fastest during the fall. By the end of November, there was no significant difference in LKP (–6.5C) between USDA 119 and 17-11, although both selections were significantly more freeze-tolerant than `Hamlin' orange (LKP–40C), which showed no significant decrease in LKP until the 6 weeks after the hybrid selections began acclimating. Citrus hybrids 17-11 and 119 can survive in freeze-susceptible areas that are marginal for other commercial citrus.

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Min Wang and Mark W. Farnham

Downy mildew, caused by Peronospora parasitica (Pers. ex Fr.), is one of the most economically important diseases in broccoli (Brassica oleracea L. Italica group). Previous studies reported that resistance to downy mildew in broccoli depends on plant age and that seedling resistance appears to be independent of mature-plant resistance. The objectives of our studies were to evaluate resistance and susceptibility of USDA broccoli inbreds to downy mildew and to investigate the interaction between the host and pathogen at two plant stages with single or double inoculation. Multiple screening tests at both cotyledon and three-expanded leaf stages using 38 entries, including USDA inbreds and commercial hybrids, were conducted in randomized complete-block designs. In these tests, every leaf of each plant was thoroughly sprayed with P. parasitica isolate PP1 at a concentration of 10,000 sporangia per ml at both stages. Ratings for downy mildew reaction phenotype were made at 9 days postinoculation on a 0-9 scale of increasing disease severity. We found significant phenotypic variation to infection among broccoli entries. We observed three general phenotypes: 1) resistance at both stages; 2) susceptible at cotyledon stage combined with resistance at three-expanded leaf stage; and 3) susceptibility at both stages. Additionally, inoculation at the cotyledon stage had no effect on inoculation at the three-expanded leaf stage.

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Dennis J. Osborne, Douglas C. Sanders, Donn R. Ward, and James W. Rushing

This paper summarizes the management framework of a multi-state, multi-institutional partnership delivering a targeted “train-the-trainer” program. Procedures associated with assuring on-schedule deliverables and budget compliance will be reviewed. The program provided Good Agricultural Practices (GAPs) and Good Manufacturing Practices (GMPs)-based training to southeastern U.S. fresh fruit and vegetable (produce) growers and packers. Twelve southern U.S. states cooperated in this project: Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia. The 2000–04 work was funded by U.S. Department of Agriculture–Cooperative State Research, Education, and Extension Service (USDA–CSREES) National Food Safety Initiative grants. This project developed materials, pilot-tested them, refined them for use by a regional group of specialized agents, assisted the agents in delivering the new programming, and evaluated the results.

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Dennis J. Osborne, Douglas C. Sanders, Donn R. Ward, and James W. Rushing

This paper summarizes the management framework of a multi-state, multi-institutional partnership delivering a targeted train-the-trainer program. The program provided Good Agricultural Practices (GAPs) and Good Manufacturing Practices (GMPs)-based training to southeastern U.S. fresh fruit and vegetable (produce) growers and packers. Twelve southern U.S. states cooperated in this project: Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia. The 2000–04 work was funded by United States Department of Agriculture – Cooperative State Research, Education, and Extension Service (USDA–CSREES) National Food Safety Initiative grants. This project developed materials, pilot tested them, refined them for use by a regional group of specialized agents, assisted the agents in delivering the new programming and evaluated the results.

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Maria M. Jenderek and Barbara Hellier

The fruit of several Opuntia species (prickly pear) are a good source of calcium, potassium, and ascorbic acid and are consumed fresh or processed as juices or preserves. Plants of Opuntia may be grown in arid and semiarid environments on marginal soils. Various cultivars, particularly in the species Opuntiaficus-indica, are grown commercially in the United States, Israel, Italy, Mexico, and South Africa. There is a need for new sources of genetic diversity and subsequent germplasm evaluation, and until recently, no publicly maintained germplasm collection of Opuntia existed in the United States. The purpose of this study was to evaluate fruit quality of 25 Opuntia accessions, originating from six countries, and maintained at the USDA collection at the National Arid Land Plant Genetic Resource Unit, Parlier, Calif. The largest fruits were harvested from plants of accessions PARL 201, 202, and 228 (227.6, 247.3, and 231.3 g/fruit, respectively). The hardest peel was on fruits of PARL 225 and 234 (both 3.7 kg), and fruit pulp of the same two accessions had the highest firmness (2.3 and 2.4 kg, respectively). Soluble solids in mature fruit varied from 6.1% (PARL 231) to 15.0% (PARL 254). The fruit color ranged from light yellow through orange, pink to dark purple. These characteristics and other traits such as fruit acidity, presence of spines, and seed mass/fruit indicated that the material represents a diverse germplasm collection, usable for future cultivar development.

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Jack E. Staub, James D. McCreight, and Juan E. Zalapa

ssp. agrestis germplasm, designated CR1 ( Fig. 1 ), was received in 1995 from Mr. Claude Hope, Cartago, Costa Rica, by the USDA-ARS Cucumber and Melon Breeding Project, Madison, WI. The early-flowering (in Wisconsin), monoecious CR1 is rapid

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Jack E. Staub, Philipp W. Simon, and Hugo E. Cuevas

) designated ‘EOM 402-10’ (in 2007) that produced true-breeding orange-pigmented fruit (i.e., orange flesh color; Fig. 1 ). Fig. 1. Greenhouse-grown fruit (2007) of USDA-ARS EOM 402-10 high β-carotene cucumber ( Cucumis sativus L.). Description Line EOM 402