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Root knot, caused by Meloidogyne spp. is the most important disease of cucumber (Cucumis sativus L.) in North Carolina, causing an average annual yield loss of 12 %. A greenhouse study was conducted 10 screen 924 cultigens (728 accessions, 136 cultivars and 36 breeding lines of C. sativus, and 24 accessions of C. metuliferus Naud.] for resistance to 3 species of root knot nematodes, M. incognita r. 3, M. arenaria r. 2 and M. hapla, Plants were grown from seed in 150-mm diameter clay pots. Two-week-old seedlings were inoculated with 5000 nematode eggs per plant, then evaluated for resistance 9 weeks later. All cultigens evaluated were resistant to M. hapla. Little resistance was found in the cultigens of C. sativus to M. incognita r. 3 and M. arenaria r. 2. Most of the cultigens evaluated were susceptible to both. `Southern Pickler' was resistant to both nematodes (1 % average galls). `Green Thumb and LJ 90430 were resistant to M. arenaria r. 2, Two check cultigens, `Sumter' and Wis. SMR 18, had an average of more than 50% galls. All C. metuliferus cultigens evaluated were resistant to all root knot nematodes tested. PI 482452 was most resistant (1 % average galls), and PI 482443 was least resistant (5% average galls) of the C. metuliferus cultigens tested.

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Scotch Bonnet and Habanero peppers, extremely pungent cultivar classes of Capsicum chinense Jacq., are increasing in popularity in the United States. Because the southern root-knot nematode, Meloidogyne incognita (Kofoid & White) Chitwood, is a major pest of many C. annuum cultivars, a series of greenhouse and field experiments was conducted to determine if Scotch Bonnet and Habanero peppers from available commercial and private sources also are vulnerable to the pest. In an initial greenhouse test, a collection of 59 C. chinense cultigens was evaluated for reaction to M. incognita race 3. All cultigens obtained from commercial sources were moderately susceptible or susceptible. However, four accessions obtained through Seed Savers Exchange listings exhibited high levels of resistance. Three of these cultigens (PA-353, PA-398, and PA-426) were studied in subsequent greenhouse and field plantings, and each was confirmed to have a level of resistance similar to that available in C. annuum. All three of the resistant cultigens are well-adapted and each is potentially useful in commercial production without further development. None of the Habanero cultigens was resistant to the southern root-knot nematode. The resistant Scotch Bonnet cultigens may serve as sources of resistance for development of root-knot nematode—resistant Habanero peppers.

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Seeds of cucumber (Cucumis sativus L.) cultigens were mixed and compared for fruit yield (Mg·ha-1) and crop value ($/ha). Three cultigen pairs (Gy 14A + M 21, Gy 4 + WI 2757, and `Regal' + `Carolina') and five component ratios of each cultigen pair (0:100, 25:75, 50:50,75:25, and 100:0) were evaluated in five plantings over a 3-year period. Fruits were harvested six to eight times for each planting date. Early and total fruit yields and crop values were greatest when either Gy 14A or Gy 4 were planted as pure stands. As the ratio of Gy 14A or Gy 4 increased in the seed mixture, the yield and crop value increased. However, when the two predominantly gynoecious hybrids, `Regal' and `Carolina', were mixed, the yield and crop value were greater than those of pure stands of either hybrid. The combination of 75% `Regal' and 25% `Carolina' resulted in higher early and total fruit yields and crop value than the other ratios of the same cultigen pair. The `Regal' + `Carolina' pair produced significantly higher early yield and early crop value (first two harvests) than did the other cultigen pairs tested. However, total yield and total value for `Regal' + `Carolina' did not differ from the Gy 14A + M 21 pair. The practice of mixing two cultivars in arbitrary combinations does not offer an advantage over single cultivars in a multiple-harvest system. In some cases, predominantly gynoecious-predominantly gynoecious mixtures may have advantages over monoecious-predominantly gynoecious cultigen mixtures if pollination is not limiting. Seed mixtures need to be evaluated to determine whether specific combinations offer advantages, as this study indicated that superior mixtures may exist.

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Green leafy vegetables are important sources of dietary carotenoids, and members of Brassica oleracea L. var. acephala rank highest for reported levels of lutein and β-carotene. Twenty-three leafy B. oleracea cultigens were field grown under similar fertility over two separate years and evaluated for leaf lutein and β-carotene accumulation. Choice of B. oleracea cultigen and year significantly affected carotenoid levels. Lutein concentrations ranged from a high of 13.43 mg per 100 g fresh weight (FW) for B. oleracea var. acephala `Toscano' to a low of 4.84 mg/100 g FW for B. oleracea var. acephala 343-93G1. β-carotene accumulations ranged from a high of 10.00 mg/100 g FW for B. oleracea var. acephala `Toscano' to a low of 3.82 mg/100 g FW for B. oleracea var. acephala 30343-93G1. Carotenoid concentrations were significantly higher in year 2 than in year 1, but rank order among the cultigens for both lutein and ß-carotene did not change between the years. During each year, there were high correlations between leaf carotenoid and chlorophyll pigments. Under similar growing conditions, choice of B. oleracea cultigen will influence carotenoid accumulation, and this may affect the health benefits of consuming these leafy green vegetable crops.

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Powdery mildew is a serious disease of melon (Cucumis melo L.) worldwide. Twenty-two melon cultigens have been used to define 22 reported races of the pathogen Podosphaera xanthii (sect. Sphaerotheca) xanthii (Castag.) U. Braun & N. Shish. Comb. nov. [syn. Sphaerotheca fuliginea (Schlecht. ex Fr.) Poll.]. Discrepancies in the reactions of eight cultigens to populations of P. xanthii races 1 and 2 in California, Japan, and Spain revealed genetic differences among them that can be used to differentiate P. xanthii race 1 and 2 populations in these countries. Implicit in these results is the existence of previously unknown virulence factors in these populations of P. xanthii races 1 and 2 that permit designation of new races of P. xanthii on melon. Synthesis of these results with previous reports resulted in the identification of 28 putative races of P. xanthii on melon that include eight variants of race 1 and six variants of race 2. Six of the cultigens exhibited resistant blisters in response to heavy infection by P. xanthii in field and greenhouse tests.

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The challenges encountered and discussions generated during the review process of the manuscripts submitted to the Variety Trials category of HortTechnology have revealed the need to review issues encountered during manuscript preparation and to provide flexible guidelines for authors and reviewers. Using a question/answer format, this manuscript discusses issues related to data collection and statistical methods available to compare varieties. Clear objectives and conclusions, adequate plot size, careful selection of entries, and sound statistical procedures are considered essential. Several additional factors (following standard production practices, using multiple seed sources, reporting analysis of variance table and mean square error, reporting multiyear/multilocation trials) are regarded as desirable, with different degrees of desirability, depending on the crop. These flexible guidelines should be viewed as recommendations for authors and reviewers rather than requirements. While defining the state-of-the-art in variety trialing is of interest to all those involved, it may be difficult to achieve when resources are limiting. It is ultimately the prerogative and responsibility of the author(s) to ensure that the work is scientifically sound.

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previous work was performed on PI accessions from the U.S. Department of Agriculture germplasm collection, which only contains ≈20 Chinese cultigens. A thorough understanding of the diversity of Chinese ecotypes has not been published. Studying the process

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pollenizers could be sold as seeded fruit as well as these that are more suitable for production with specific triploid cultivars. Materials and Methods Treatments. Thirteen pollenizer cultigens were evaluated: ‘Companion’, ‘Jenny’, ‘High Set 11’, ‘Mickylee

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. charantia , cultivated landraces and cultivars, i.e., cultigens, are grown ubiquitously on the countryside in rural agricultural areas. Recently, phenotypic- and DNA marker-based [random amplified polymorphic DNA (RAPD); Dey et al., (2006) and intersimple

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