Location: Vegetable Crops Research
Project Number: 5090-21000-069-13-A
Project Type: Cooperative Agreement
Start Date: Jun 1, 2016
End Date: May 31, 2019
1. Perform genotyped by sequencing (GBS) analysis of PI collections and core populations of cucumber; 2. Genome-wide association study for cucumber; 3. Fine genetic mapping of downy mildew resistance in cucumber; and 4. Develop downy mildew resistant breeding lines through marker-assisted selection.
1. Over 1500 USDA PI collections will be genotyped by sequencing (GBS). Bioinformatic analysis of sequencing data will identify target lines to formulate a genome-wide association studies (GWAS) panel; 2. A GWAS panel of 384 PI lines will be selected and genotyped through extensive phenotyping in field and greenhouse experiments; 3. Alleles for disease resistances and other traits will be identified through GWAS analysis; 4. Fine genetic mapping of downy mildew resistance will be conducted in biparental segregating poulations; and 5. Molecular markers closely linked with downy mildew resistance in PI 330628 will be used to introgress major-effect quantitative trait loci (QTL) into elite pickling cucumber lines through marker-assisted selection.