@article{siddique_silverman_louws_panthee_2024, title={Quantitative Trait Loci Mapping for Bacterial Wilt Resistance and Plant Height in Tomatoes}, volume={13}, ISSN={["2223-7747"]}, url={https://doi.org/10.3390/plants13060876}, DOI={10.3390/plants13060876}, abstractNote={Bacterial wilt (BW) of tomatoes, caused by Ralstonia solanacearum, is a devastating disease that results in large annual yield losses worldwide. Management of BW of tomatoes is difficult due to the soil-borne nature of the pathogen. One of the best ways to mitigate the losses is through breeding for disease resistance. Moreover, plant height (PH) is a crucial element related to plant architecture, which determines nutrient management and mechanical harvesting in tomatoes. An intraspecific F2 segregating population (NC 11212) of tomatoes was developed by crossing NC 84173 (tall, BW susceptible) × CLN1466EA (short, BW resistant). We performed quantitative trait loci (QTL) mapping using single nucleotide polymorphic (SNP) markers and the NC 11212 F2 segregating population. The QTL analysis for BW resistance revealed a total of three QTLs on chromosomes 1, 2, and 3, explaining phenotypic variation (R2) ranging from 3.6% to 14.9%, whereas the QTL analysis for PH also detected three QTLs on chromosomes 1, 8, and 11, explaining R2 ranging from 7.1% to 11%. This work thus provides information to improve BW resistance and plant architecture-related traits in tomatoes.}, number={6}, journal={PLANTS-BASEL}, author={Siddique, Muhammad Irfan and Silverman, Emily and Louws, Frank and Panthee, Dilip R.}, year={2024}, month={Mar} }
 @article{rivera-burgos_silverman_sari_wehner_2021, title={Evaluation of Resistance to Gummy Stem Blight in a Population of Recombinant Inbred Lines of Watermelon x Citron}, volume={56}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI15599-20}, abstractNote={Gummy stem blight (GSB), a major disease caused by Stagonosporopsis cucurbitacearum (syn. Didymella bryoniae), has caused significant losses of watermelon in the United States. The lack of progress in the development of resistant cultivars is the result of complex inheritance of resistance and breeding strategies that rely on single-plant selection. Because the sources of resistance are wild watermelon relatives, good fruit quality has been difficult to maintain during the selection process. Three hundred recombinant inbred line (RILs) in a population that carries resistance genes to GSB as well as good fruit quality were produced. This was accomplished by crossing and intercrossing resistant plant introductions, crossing the resulting progenies with elite cultivars, intercrossing those progenies, and, finally, self-pollinating to the S3 generation. The 300 RILs were evaluated for disease severity and fruit morphological and quality traits under greenhouse and field conditions in a randomized complete block design with 10 replications and 3 years. The means and correlations for disease severity ratings and fruit quality traits were estimated. Approximately 186 RILs had disease severity ratings below the mean value of the disease assessment scale (4.5), indicating that they possibly carry one or more genes for resistance to GSB. All disease severity ratings were correlated to each other (r = 0.67–0.98; P < 0.001), but they were not correlated with fruit quality traits. Most importantly, several resistant RILs showed good to excellent fruit quality. Our results provide evidence of improved germplasm with high resistance and good fruit quality.}, number={3}, journal={HORTSCIENCE}, author={Rivera-Burgos, Luis A. and Silverman, Emily and Sari, Nebahat and Wehner, Todd C.}, year={2021}, month={Mar}, pages={380–388} }
 @article{rivera-burgos_silverman_wehner_2021, title={NC-GSB-524W, NC-GSB-527W, NC-GSB-528W, NC-GSB-530W, NC-GSB-531W, and NC-GSB-532W Watermelon Lines with Gummy Stem Blight Resistance and Good Fruit Quality}, volume={56}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI16095-21}, abstractNote={Gummy stem blight (GSB) is a major disease of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] that leads to significant economic losses. This disease is caused by three genetically distinct Stagonosporopsis species, S. cucurbitacearum (syn. Didymella bryoniae), S. citrulli, and S. caricae (Stewart et al., 2015). The three species are pathogenic to cucurbits, but S. caricae also causes leaf spot, stem rot, and fruit rot in papaya (Carica papaya L.) (Stewart et al., 2015). GSB was first observed in 1891 by Fautrey and Roumeguere in France on cucumber (Cucumis sativus L.) and in Delaware on watermelon (Sherf and MacNab, 1986). In 1917, GSB was reported in the southern United States, affecting watermelon fruit in Florida (Sherbakoff, 1917). GSB remains an important limiting factor for watermelon production in Florida (Keinath, 1995) and South Carolina (Rennberger et al., 2018, 2019). This disease also affects watermelon production in some important watermelon producing countries (Basim et al., 2016; Huang and Lai, 2019). GSB on watermelon plants is evident as crown blight, stem cankers, and extensive defoliation, with symptoms observed on the cotyledons, hypocotyls, leaves, and fruit (Maynard and Hopkins, 1999). Stagonosporopsis cucurbitacearum is seed-borne (Lee et al., 1984), airborne (van Steekelenburg, 1983), and soilborne (Bruton, 1998). There are seven species of Citrullus: C. lanatus (Thunb.) Matsum. & Nakai is the dessert watermelon. It is closely related to egusi watermelon [C. mucosospermus (Fursa) Fursa]. Slightly less related is citron (C. amarus Schrad). Other related species include C. ecirrhosus Cogn. (the tendril-less melon), C. rehmii De Winter, C. colocynthis (L.) Schrad., and C. naudinianus (Chomicki and Renner 2015; Levi et al., 2017). All are cross-compatible to varying degrees. Crosses of citron and dessert watermelon may result in progeny having preferential segregation, and reduced pollen fertility (Levi et al., 2003). That makes it difficult, although not impossible, to obtain new (nonparental) combinations in plant breeding programs. In previous studies, plant introduction (PI) 189225 was identified as the most resistant accession in the USDA-ARS watermelon germplasm collection (Sowell and Pointer, 1962). Later, PI 271778, PI 500335, PI 505590, PI 512373, PI 164247 and PI 500334 were also identified as GSB resistant (Boylan et al., 1994). When resistant PI 189225 was crossed with susceptible ‘Charleston Gray’, a single recessive gene (db) was identified controlling the resistance (Norton, 1979). To develop resistant cultivars with yield and quality, PI 189225 and PI 271778 were chosen as resistant parents in crosses with ‘Crimson Sweet’ and ‘Jubilee’. Cultivars having good fruit quality}, number={12}, journal={HORTSCIENCE}, author={Rivera-Burgos, Luis A. and Silverman, Emily J. and Wehner, Todd C.}, year={2021}, month={Dec}, pages={1599–1604} }
 @article{sari_silverman_reiland_wehner_2020, title={Effects of Cold Durations on Chilling Injury in Lagenaria Germplasm}, volume={55}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI15184-20}, abstractNote={Cucurbit plants usually are sensitive to chilling and easily damaged. Although bottle gourds, which are members of the Cucurbitaceae family, are considered as fresh vegetables in some Asian countries, their main use in recent years is to be used as rootstocks in grafted watermelon cultivation. We tested 163 bottle gourd accessions of the U.S. Department of Agriculture (USDA) genebank for cold tolerance in the early seedling stage. The experiment was conducted using controlled environment chambers with 3 chilling durations (36, 48, and 60 hours) at 4 °C. Chilling damage was rated 0 to 9 (0 = no damage, 1 to 2 = trace of damage, 3 to 4 = slight damage, 5 to 6 = moderate damage, 7 to 8 = advanced damage, 9 = plant totally dead). We rated damage separately for the cotyledons, true leaf, and growing point. Cold damage was higher at a chilling duration of 60 hours, and decreased at 48 and 36 hours. Most tolerant cultigens were PI 491272, PI 491280, PI 491281, PI 491286, and PI 491326. Most susceptible were PI 381845, PI 381846, PI 534556, PI 636137, and PI 668365.}, number={10}, journal={HORTSCIENCE}, author={Sari, Nebahat and Silverman, Emily and Reiland, Danny and Wehner, Todd C.}, year={2020}, month={Oct}, pages={1551–1557} }
 @article{sari_silverman_reiland_wehner_2021, title={Seed Characterization and Relationships between Seed and Cotyledon Properties in Lagenaria spp. Accessions}, volume={56}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI15569-20}, abstractNote={Bottle gourd [Lagenaria siceraria (Molina) Standl.] is widely produced in some Asian and African countries as a fresh vegetable as well as for seed consumption. A major use of bottle gourd is for rootstocks in grafted watermelon production. There are several centers where bottle gourd genetic resources are maintained, with the U.S. Department of Agriculture (USDA) germplasm collection being one of the most important. There is little published information on the relationship between seed morphology and the early establishment of seedlings in bottle gourd. The objective of this study was to determine seed characterization, morphology, and cotyledon shape in 163 Lagenaria spp. accessions and measure any relationship between seed and cotyledon characteristics. In USDA Lagenaria germplasm, it has been determined that the common character in seeds was medium in terms of seed size (53% of accessions), intermediate in seed surface lustre (39% of accessions), brown in seedcoat color (89% of accessions), thin and uniform in seed margin (35% of accessions), and tan in seed margin color (64% of accessions). According to the research results, seed weight ranged from 0.11 g (PI 500820) to 0.36 g (PI 675112), seed length from 13.17 mm (PI 500820) to 23.68 mm (PI 675112), and seed width from 5.86 (PI 500808) to 11.21 mm (PI 491274). Cotyledon length ranged from 5.46 cm (PI 368640) to 2.47 cm (PI 381850). The widest cotyledon was 3.00 cm (PI 534552), and the narrowest was 1.50 cm (PI 381831). Interesting correlations were observed for seed weight with seed length (R2 = 0.259), and cotyledon length with cotyledon width (R2 = 0.547).}, number={2}, journal={HORTSCIENCE}, author={Sari, Nebahat and Silverman, Emily and Reiland, Danny and Wehner, Todd C.}, year={2021}, month={Feb}, pages={185–192} }