The cucumber line WI2757 has been an important sources of disease resistances for cucumber breeding, but it has some drawbacks including later flowering and poor growth under field conditions. The genetic basis for these traits is not known. Researchers in Dr. Yiqun Weng’s lab at USDA-ARS conducted molecular mapping using populations involving WI2757, and uncovered a large paracentric inversion of about 10 megabases in length on cucumber chromosome 1 of WI2757. They found that inversion region harbors genes or quantitative trait loci for fruit length, diameter, fruit shape, fruit number, and flowering time.
In early 2020, CucCAP Vegetable Pathology and Crop Production Extension Specialists published plant disease management reports and Cucurbit cultigen evaluations from recent field trials. These reports provide valuable information for cucurbit crop producers, seed companies and other CucCAP stakeholders. The 2019 Plant Disease Management Reports provide disease resistance information for downy mildew on cucumber, Phytophthora […]
In recent years, significant progress has been made in molecular mapping and identification of genes and QTL responsible for key phenotypic traits. CucCAP scientists and collaborators led by Drs. Yuhui Wang and Yupeng Pan from Dr. Yiqun Weng’s lab at the University of Wisconsin at Madison provide an extensive review of the literature to systematically […]
Fusarium wilt (FW) and papaya ring-spot virus-watermelon strain (PRSV-W) are important diseases of watermelon, causing serious damage to the crop. Multiple disease screens of the USDA watermelon germplasm collection have highlighted the value of wild type watermelons as a source for enhancing resistance to diseases in modern watermelon cultivars. The CucCAP team at the USDA, […]
The occurrence of powdery mildew of watermelon has significantly increased in recent years. While the majority of the watermelon varieties evaluated in South Carolina were susceptible to powdery mildew, the seedless variety Suprema and seeded variety Declaration were relatively less susceptible and the commercial pollenizers Lion, SP5 and SP6 were resistant across three years of testing. Because of the frequent […]
Watermelon has been domesticated for more than 4000 years and modern sweet watermelons have been selected to carry large fruits with crisp, non-bitter and sweet flesh. The CucCAP team has co-led an international effort to generate an improved watermelon ‘97103’ reference genome and resequence 414 accessions from the seven extant Citrullus species.
Bacterial fruit blotch (BFB) of cucurbits caused by Acidovorax citrulli has the potential to devastate production of watermelon and other cucurbits. Despite decades of research, no watermelon germplasm has been found with immunity, and only a few sources with various levels of resistance have been identified.
CucCAP Vegetable Pathologists provide cucurbit producers with techniques for cucurbit disease management and connect growers with research seeking new solutions for cucurbit diseases. The extension team is a network of University Extension specialists, members of their labs and Extension Agents who work with growers from across each state. Extension Agent Training When cucurbit crops are threatened by […]