Location: Sunflower and Plant Biology Research
Project Number: 3060-21000-039-10-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 1, 2012
End Date: Jun 30, 2017
The goal of this project is threefold: (1) to find new sources of Sclerotinia head rot resistance in cultivated sunflower germplasm, (2) to improve existing methods of ascospore production and assess them across multiple laboratories, and 3) to transfer Sclerotinia stalk and head to resistance by conventional breeding and marker-assisted selection (MAS) into elite USDA sunflower germplasm for release to the public. Specifically, the project will (1) evaluate new cultivated sunflower accessions of the USDA Plant Introduction Station’s seed collection for resistance to head rot; (2) use the phenotype data for head rot and stalk rot in association mapping; (3) test modifications of ascospore production using the method developed by Dr. M. Boosalis, at multiple laboratories; and (4) cross new sources of Sclerotinia resistance into elite oilseed and confection USDA germplasm.
To increase the genetic diversity of Sclerotinia resistance within the USDA breeding program, we will evaluate both the newest USDA Plant Introductions (which have not been tested for disease resistance) and seek new germplasm via exchanges with foreign public breeding programs. The evaluations will be done with artificial inoculations at multiple test sites in North Dakota and Minnesota. Once new sources of stalk rot and head rot resistance are identified, we will determine with the aid of MAS whether these contain new genes. Once resistance sources are identified, they will be crossed into either elite oilseed or confection lines. Dr. M. Boosalis, retired Plant Pathology chairman at U. Nebraska, has been producing Sclerotinia ascospores for 25+ years with a proprietary, unpublished protocol. We will work with him to test his method with several Sclerotinia isolates at four laboratories to assess the method’s general applicability.