@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{guner_pesic-vanesbroeck_rivera-burgos_wehner_2019, title={Screening for Resistance to Zucchini yellow mosaic virus in the Watermelon Germplasm}, volume={54}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI13325-18}, abstractNote={The Florida strain of Zucchini yellow mosaic virus (ZYMV-FL) is one of the major viral diseases of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai]. Although some screening has been performed for ZYMV resistance in watermelon, the germplasm collection has not been screened extensively for resistance. The objectives of this study were to screen the U.S. Department of Agriculture (USDA) watermelon germplasm collection for ZYMV resistance and to verify the disease rating for the most resistant and most susceptible accessions. We used a randomized complete block with four replications, 1613 PI accessions, and 41 cultivars. ‘Charleston Gray’ and ‘Crimson Sweet’ susceptible controls were used to verify that the ZYMV inoculum was virulent. After the last rating, an enzyme-linked immunosorbent assay (ELISA) was performed to determine the presence of a virus in the plant tissue. The PI accessions with high resistance to ZYMV-FL that also exhibited resistance to other watermelon viruses were PI 595203, PI 386015, PI 386016, PI 386024, PI 386025, PI 386026, PI 244018, PI 244019, PI 485583, PI 494528, and PI 494529. The ZYMV-FL retest of the most resistant 46 PI accessions showed that there were some escapes. Sixteen resistant PI accessions had a rating of 3.0 or less for the average and maximum ratings: PI 595203, PI 537277, PI 560016, PI 386016, PI 386019, PI 485580, PI 494529, PI 595200, PI 494528, PI 595201, PI 386025, PI 494530, PI 386015, PI 386021, PI 386026, and PI 596662. Overall, PI 595203 had the highest resistance according to both the germplasm screening and the retest studies.}, number={2}, journal={HORTSCIENCE}, author={Guner, Nihat and Pesic-VanEsbroeck, Zvezdana and Rivera-Burgos, Luis A. and Wehner, Todd C.}, year={2019}, month={Feb}, pages={206–211} }
 @article{guner_pesic-vanesbroeck_rivera-burgos_wehner_2018, title={Inheritance of Resistance to Papaya Ringspot Virus-Watermelon Strain in Watermelon}, volume={53}, ISSN={0018-5345 2327-9834}, url={http://dx.doi.org/10.21273/hortsci12944-18}, DOI={10.21273/hortsci12944-18}, abstractNote={Sources of resistance to the watermelon strain of papaya ringspot virus-watermelon strain (PRSV-W) have been identified within the watermelon (Citrullus lanatus) germplasm collection. Inheritance of the resistance to PRSV-W was studied in three Citrullus amarus (formerly C. lanatus var. citroides) PI accessions: PI 244017, PI 244019, and PI 485583. Three susceptible parent lines, ‘Allsweet’, ‘Calhoun Gray’, and ‘New Hampshire Midget’, were crossed with resistant PI accessions to develop F1, F2, and BC1 progenies in six families. A single recessive gene was found to control the resistance to PRSV-W in all three resistant PI accessions. Allelism tests indicated that the three PI accessions carry the same resistance allele to PRSV-W. The gene symbol ‘prv’ is proposed for PRSV-W resistance in PI 244017, PI 244019, and PI 485583 in watermelon.}, number={5}, journal={HortScience}, publisher={American Society for Horticultural Science}, author={Guner, Nihat and Pesic-VanEsbroeck, Zvezdana and Rivera-Burgos, Luis A. and Wehner, Todd C.}, year={2018}, month={May}, pages={624–627} }