2012 Annual Report
1a.Objectives (from AD-416):
We will expand close working relationships among breeders, extensionists, and growers of major Alliums in the U.S. to evaluate germplasms for prioritized pest resistances (thrips and Iris Yellow Spot Virus) and lay the foundation for the long-term translational genomics of the Allium vegetables. Workshops will be held at regional onion meetings.
We will evaluate in the field onion populations for resistance or tolerance to thrips and Iris Yellow Spot Virus. Resistance or tolerant germplasms will be released to the onion breeders in the public and private sectors.
1b.Approach (from AD-416):
Work with extension professionals to empower growers to complete on-farm evaluations for resistances or tolerances to thrips and Iris Yellow Spot Virus. Self-pollinate and testcross selected plants and return seed for validation of phenotypes; Deliver validated germplasms to private and public sector breeders; Develop workshops for public and private-sector researchers, students, and regional grower and consumer groups for onion to illustrate the usefulness of genomics to solve high-priority research goals.
Germplasm was identified that possessed foliage characteristics associated with onion thrips feeding nonpreference. In addition, germplasm was identified that possess a reduced number of thrips per plant than most entries. Both of these characteristics suggest that there is the genetic potential for reduced thrips feeding and possibly reduced Iris yellow spot virus (IYSV) spread. Entries were identified that exhibited less severe IYS disease symptoms than most entries. Selection for reduced thrips number and IYS disease severity appears to be effective. Additional cycles of selection may be beneficial for increasing tolerance to thrips and/or IYSV.
This research relates to Objective 1, Determine the genetic basis of and initiate selection for carrot, onion, cucumber, and melon quality attributes influencing human nutrition and health, disease resistances, and yield and quality components, and stress tolerance in cucurbits, and perform field performance and quality trials; Objective 2, Utilize current biotechnology to discover and evaluate genetic variation and to map agriculturally important traits in Allium, Cucurbit, and Daucus germplasm, and to develop genetic and breeding stocks.