Phytophthora fruit rot is a major disease impacting pickling cucumber production for which there are no resistant varieties. Genomic approaches were performed on the cucumber core collection leading to identification and verification of several quantitative trait loci associated with resistance. The results from this work can be applied to future disease resistance studies and to assist marker-assisted selection in breeding programs.
Featured Articles
The CucCAP website features recently published articles from the four crop teams, (Cucumber, Melon, Squash, and Watermelon) and the Bioinformatics, Breeding, & Genomics group. Integtated crop and disease management activities, articles and reports are also featured.
CucCAP scientists uncover genetic factors influencing flowering time and fruit yield in watermelon
Scientists at the USDA, ARS, U.S. Vegetable Laboratory in Charleston, SC evaluated the USDA, ARS citron watermelon germplasm collection for flowering time and fruit yield traits under field conditions over two years. They used a “genome-wide association study (GWAS)” to detect genomic regions and molecular (DNA) markers associated with flowering time and fruit yield traits. The new molecular markers will be useful in improving watermelon varieties for early flowering and maturity and yield performance via marker-assisted breeding.
CucCAP scientists evaluate disease forecasting models for downy mildew control in cucumber
Cucurbit downy mildew is a major threat for pickling cucumber production requiring frequent fungicide applications.
CucCAP scientists develop a super-pangenome for watermelon
A super-pangenome was constructed to represent the entire watermelon gene repertoire, uncovering several disease resistance genes that are present in wild watermelons while completely lost in watermelon cultivars.
CucCAP scientists find high prevalence of gummy stem blight resistance to common fungicides
The gummy stem blight fungus, Stagonosporopsis citrulli, is now resistant to fungicides in four chemical classes. The newest resistance is to fungicides in FRAC Code 3.
CucCAP scientists perform genome-wide association study to identify resistances to Pseudomonas leaf spot in watermelon
Citrullus amarus was screened for resistance to Pseudomonas leaf spot. Genetic markers associated with resistance to P. syringae and other diseases were identified. The results will facilitate breeding for resistance to PLS in watermelon.
CucCAP scientists identify gene for short-vining cucumber plants
The compact (cp) phenotype in cucumber is an important plant architecture-related trait with potential for breeding short-vining cucumber plants for high density planting and mechanized harvest.
CucCAP scientists use multiplex system to monitor virus threats to melon crops in California and Arizona
The Wintermantel team developed a multiplex single-step RT-PCR method to simultaneously test and differentiate among the among different viruses. Sampling of melon production regions in California and Arizona found that different combinations of viruses were dominant in fall vs. spring seasons, providing important information for disease management in areas impacted by cucurbit yellowing viruses.