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Gummy stem blight (Didymella bryoniae (Auersw.) Rehm) is one of the major cucumber diseases, causing the second highest loss of any disease in North Carolina. Published methods of screening for resistance to this fungus are poorly correlated with field resistance. The objective of this study was to develop seedling or detached-leaf screening methods that are correlated with field resistance. Seedling tests examined the effects of: seedling age (1, 2 or 3 true leaves), days in humidity chamber, inoculum concentration (1×105, 1×106 or 1×107 spores per ml), time of inoculation (am vs. pm), fungal isolates, and cultigens. Detached leaf tests examined the effects of leaf age (1st, 2nd or 3rd true leaf), inoculum concentration (1×104, 1×105 or 1×106 spores per ml), and light levels during incubation (dark vs. 12h light/12h dark). Correlations between seedling tests and field data were moderate to high (r = 0.5 to 0.7). However, the coefficients of variation were also high. Correlations between detached leaf tests and field data were very low or negative.

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Greenhouse tests were conducted to compare the levels of resistance to the southern root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] exhibited by recently released Capsicum chinense Jacq. Scotch Bonnet-type germplasm lines PA-353, PA-398, and PA-426 to the levels of resistance exhibited by C. annuum L. `Carolina Cayenne' and `Mississippi Nemaheart'; to determine the inheritance of the resistance in C. chinense germplasm line PA-426; and to determine the genetic relationship between the resistances exhibited by C. chinense germplasm line PA-426 and C. annuum `Carolina Cayenne'. The results of a replicated test indicated that the level of resistances exhibited by the resistant released C. chinense germplasm lines is equal to the level of resistances exhibited by the resistant C. annuum cultivars. Evaluation of parental, F1, F2, and backcross populations of the cross PA-426 × PA-350 (a susceptible Habanero-type C. chinense cultigen) indicated that the resistance in C. chinense is conditioned by a single dominant gene. The results of an allelism test indicated that this dominant gene is allelic to the dominant gene that conditions much of the southern root-knot nematode resistance in the C. annuum `Carolina Cayenne'. The ease and reliability of evaluating plants for resistance to root-knot nematode and the availability of a simply inherited source of outstanding resistance makes breeding for southern root-knot nematode resistance a viable objective in C. chinense breeding programs.

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Greenhouse experiments determined the inheritance of resistance to the peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood race 1] in Capsicum chinense Jacq. germplasm lines PA-353 and PA-426. Evaluation of parental, F1, F2, and backcross populations of the crosses PA-353 × PA-350 and PA-426 × PA-350 (PA-350 is a susceptible cultigen) indicated that resistance in both C. chinense germplasm lines was conditioned by a single dominant gene. Evaluation of the F1 × resistant parent backcross populations in the cytoplasm of their respective resistant and susceptible parents indicated that the cytoplasm of the resistant parent is not needed for full expression of resistance. Allelism tests indicated that the dominant resistance gene in both PA-353 and PA-426 is allelic to a resistance gene in C. annuum L. `Carolina Cayenne'. However, these allelism tests did not demonstrate conclusively that the M. arenaria race 1 resistance gene in C. chinense is the N gene that conditions resistance to the southern root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] in C. annuum. The ease and reliability of evaluating plants for resistance to root-knot nematodes and the availability of simply inherited sources of resistance makes breeding for peanut root-knot nematode resistance a viable objective in C. chinense breeding programs.

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Scientific disagreement about criteria for accurate classification of similar, if not seemingly identical, cultivars has led to spirited debate in legal and agricultural communities. The lack of universally acceptable working definitions of functional genetic distance and difference, as well as insufficient data on genetic diversity, has made it difficult to define a legal framework for cultivar discrimination. In order to satisfy the “distinctness” criterion during plant patenting, genetic diversity and difference must be described unequivocally in measurable terms. Moreover, the number of markers or other characteristics needed to identify the “nonobvious” nature of the cultigen will determine the breadth of protection under the patent. Increasingly, patent examiners must interpret novelty and distinctness in terms of molecular as well as gross phenotypic (flower color, plant habit, etc.) information. A description of difference using molecular markers may be more difficult compared to a description of function (i.e., how many markers are required to assign difference). Consequently, the effective use of molecular marker information in the legal community will require scientific agreement on the meaning of genetic distance as it relates to genetic difference.

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The Habanero pepper, a distinct cultigen of Capsicum chinense, has become increasingly popular in American markets due to its unique flavor and aroma. It is extremely pungent compared to other commonly cultivated hot peppers. This attribute restricts its culinary uses. The objective of the Habanero pepper improvement project was to breed for important flavor compounds in the absence of genes involved in capsaicin synthesis. Intensive selection in large breeding populations was carried out to identify individual plants producing fruit with good aroma and flavor and low capsaicin concentrations. An initial cross was made between a non-pungent selection of C. chinense out of PI 543188 and a highly pungent, typical Habanero pepper from Yucatan. A series of sib-selections following a single backcross of a non-pungent F2 individual to the Habanero line were carried out in field and greenhouse plantings at Weslaco. Six subsequent generations of inbreeding resulted in a highly uniform, novel variety-TAM Mild Habanero (TMH). The fruit of TMH is very similar in size and shape to the recurrent parent. Color is yellow-orange as opposed to the deep orange of the Yucatan Habanero (YH), but aroma and flavor are extremely similar. In contrast, total capsaicin concentration of TMH fruit at Weslaco averaged 154 μg·g-1, compared to 12,704 μg·g-1 for the YH. Field trials conducted in south Texas showed that TMH consistently matured about 10 days earlier, had significantly higher levels of beta-carotene (7.6 μg·g-1 compared to <0.5 μg·g-1 in YH) and out-yielded YH by 25%. These traits make TMH an ideal cultivar for Fall production in south Texas.

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. Variance components were estimated for additive and environmental, additive × environment, and other components of interest. The equation used here was specific to heritability calculations for half-siblings, where σ 2 F is family (cultigen-wise variance

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experimental hybrids (cultigens) were evaluated in field locations in the southeastern United States. Hassell et al. (p. 608) found that eight cultigens were consistently among the highest yielding, and that four cultigens were consistently among the lowest

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and Thies, 1997 , 1998a , 1998b ). PA-350, susceptible to southern root-knot nematodes, is a classical, Habanero-type cultigen obtained from an heirloom collector. In 2002, a total of 63 BC4F3 populations were evaluated in a greenhouse test for

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-type cultigen obtained from an heirloom collector. ‘TigerPaw-NR’ was derived from a single BC 4 F 3 plant grown in 2002. Description ‘TigerPaw-NR’ has a compact plant habit (height = 62 cm, width = 86 cm) and produces lantern-shaped, orange

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Habanero-type cultigen obtained from an heirloom collector. In 2002, a total of 63 BC4F3 populations were evaluated in a greenhouse test for reaction to M. incognita and in a replicated field test for horticultural characteristics. Although superior, root

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