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Claire H. Luby, Rachael Vernon, Hiroshi A. Maeda, and Irwin L. Goldman

1.91–7.03 mg·kg −1 total tocopherols on a fresh weight basis, which were relatively similar to levels reported by Ombodi et al. (2014) . The NNB is produced by the USDA (2014) . This searchable and downloadable database serves as a standard for

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Jack E. Staub and Isabelle Y. Delannay

selected from 42 accessions [20 elite cucumber lines, 17 diverse PIs from the U.S. National Plant Germplasm System (NPGS) ( Horejsi and Staub, 1999 )] and five breeding lines from the U.S. Department of Agriculture, Agricultural Research Service (USDA, ARS

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A.G. Gillaspie, O.L. Chambliss, R.L. Fery, A.E. Hall, J.C. Miller Jr., and T.E. Morelock

The Vigna Crop Germplasm Committee has established a core subset for the USDA cowpea germplasm collection. The subset consists of 9.3% (700 accessions) of the 7525 accessions currently contained in the collection. The subset was selected on the basis of country of origin, taxonomic characteristics, and known disease and pest resistance characteristics. Theoretically, the lines in the subset represent the genetic diversity present in the entire collection. A listing of the accessions in the subset is available from the Vigna germplasm curator (A.G. Gillaspie). The listing can also be accessed through the USDA's Germplasm Resources Information Network (GRIN).

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J.M. Spiers

The Southern Horticultural Laboratory evolved from the USDA Small Fruit Research Station located at Poplarville, MS. A short history of the research facility and present horticultural research directions will be discussed. Emphases will be on past and present cooperative regional research efforts in horticultural crops.

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Barbara C. Hellier and Marie Pavelka

The USDA garlic (Allium sativum and Allium longicuspis) collection is maintained at the ARS, Western Regional Plant Introduction Station (WRPIS) in Pullman, Wash. This collection comprises 269 accessions, of which 153 are hardneck (flower producing) types. The fertility characteristics of these accessions was evaluated in the field at Pullman, Wash. After the spathes opened, bulbils were removed from all the evaluated accessions to facilitate flower development. The umbel and flower characteristics taken were anther color, flower color, flower shape, stigma position, flowers per umbel, umbel diameter, umbel shape, umbel defects, bulbil size, bulbil color, ease of bulbil removal, spathe opening, pollen production, and pollen viability. Of the 153 accessions, 10 produced only partial scapes with bulbils midstalk and no seed production capability. Viable pollen was shed in 85 accessions with viability ranging from 8% to 85%. Open-pollinated seed was generated by 19 of the Pullman, Wash., grown accessions. Seed production was low with yields from 6 to 91 seeds per accession.

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

Two USDA intergeneric, hybrid citrus scions, US 119 {[Citrus paradisi Mac. `Duncan' × Poncirus trifoliata (L.) Raf.] × C. sinensis Osb. `Succory'} and selection 17-11 {C. grandis US 145 × [Citrus paradisi Mac. `Duncan' × P. trifoliata (L.) Raf.]} on `Swingle' citrumelo (C. paradisi × P. trifoliata) rootstocks were examined for freeze hardiness traits (4 years) and general growth characteristics (2 years). Hardiness was compared with that of `Hamlin' orange [C. sinensis (L.) Osb.] and satsuma mandarin (C. unshiu Marc) from Fall 1993 to Spring 1997. As expected, US 119 and 17-11 were both hardier than `Hamlin' orange as determined by leaf disc electrolyte leakage (EL). Both showed freezing tolerance similar to that of satsuma mandarin, but 17-11 was significantly hardier than satsuma or US 119 at several times during the 4-year study. Trunk diameter and tree height were similar for US 119 and selection 17-11.

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Maria M. Jenderek and Richard M. Hannan

Diverse garlic germplasm has proven to be essential for production of true seed. Yet, fertile accessions in garlic germplasm collections have not been characterized for breeders and researchers, and information on morphological characteristics associated with seed producing plants is very limited. The objective of this study was to evaluate reproductive characteristics and true seed production capacity in the USDA garlic germplasm collection. Most stable traits, such as flower stem appearance, opening ability of spathe, level of difficulty to remove bulbils, tepal color, umbel shape, and the number of flowers per umbel, were similar across populations evaluated. Other characteristics including position of stigma, tepal closure, pollen viability, time of flowering, scape senescence rate, and number of seeds produced by individual plants varied within accession evaluated. Of 47 accessions, 19 produced true seeds (from 48.5 to 1.5 seeds per plant) in the Central Valley of California. Seed production in the germplasm evaluated is adequate to initiate garlic breeding projects.

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Maxine M. Thompson and Kim E. Hummer

Chromosome numbers were determined for the Rubus species and cultivars held at the USDA/ARS National Clonal Germplasm Repository, Corvallis, Ore. Counts were made on a total of 205 taxa; 81 of which were new, 124 were corrections, and a few were corrections of previous reports. The numbers ranged from 2n = 2x = 14 to 2x = 98, and included odd-ploids and aneuploids. Knowledge of the chromosome number of a plant is important for its use in breeding because of potential sterility problems that may arise due to unbalanced gametes. The value of these particular counts are that they are vouchered by a permanent, living plant collection that is available to the scientific user community.

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Elizabeth Baldwin

The USDA–ARS Citrus and Subtropical Products Laboratory is a food science and postharvest facility for fresh and processed fruits and vegetables of tropical and subtropical origin. The term “tropical” is extended to vegetables grown during the summer of temperate climates like tomato. There are also projects involving strawberry and blueberry since these are important crops for Florida. The majority of the work, however, is on citrus (70%). There are four projects at the facility including quality and by-product research. The two quality projects involve work on juice (mainly citrus juices) and fresh fruit flavor. The other quality project includes work on edible coatings or other surface treatments to reduce decay, water loss and to improve of the appearance of fresh or fresh-cut fruits and vegetables. The two by-product projects aim to develop products from citrus processing waste. One project mines citrus waste for edible fiber, nutraceuticals and compounds in grapefruit that enhance uptake of certain drugs. The other by-product project seeks to develop industrial products from the carbohydrates in citrus peel such as suspension aids and fuel ethanol.

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William C. Johnson, Phil L. Forsline, Herb S. Aldwinckle, William C. Johnson, Phil L. Forsline, H. Todd Holleran, Terence L. Robinson, and John J. Norelli

In 1998, the USDA-ARS and Cornell Univ. instituted a cooperative agreement that mobilized the resources for a jointly managed apple rootstock breeding and evaluation program. The program is a successor to the Cornell rootstock breeding program, formerly managed by Emeritus Professor of Horticultural Sciences James N. Cummins. The agreement broadens the scope of the program from a focus on regional concerns to address the constraints of all the U.S. apple production areas. In the future, the breeding program will continue to develop precocious and productive disease-resistant rootstock varieties with a range of vigor from fully dwarfing to near standard size, but there will be a renewed emphasis on nursery propagability, lodging resistance, tolerance to extreme temperatures, resistance to the soil pathogens of the sub-temperate regions of the U.S., and tolerance to apple replant disorder. The program draws on the expertise available at the Geneva campus through cooperation with plant pathologists, horticulturists, geneticists, biotechnologists, and the curator of the national apple germplasm repository. More than 1000 genotypes of apple rootstocks are currently under evaluation, and four fire blight- (Erwinia amylovora) resistant cultivars have been recently released from the program. As a service to U.S. apple producers, rootstock cultivars from other breeding programs will also be evaluated for productivity, size control, and tolerance to a range of biotic and abiotic stress events. The project will serve as an information source on all commercially available apple rootstock genotypes for nurseries and growers.