Field Evaluation of Wheat Blast of Us Wheat Germplasm in Paraguay
Foreign Disease-Weed Science
2013 Annual Report
1a.Objectives (from AD-416):
1. Evaluation of U.S. wheat germplasm for resistance to wheat blast.
2. Development of new resistant germplasm.
3. Collection of new wheat pathotypes for M. oryzae for diagnostics development.
4. Collection of M. oryzae isolates from wild grasses in Paraguayan fields.
1b.Approach (from AD-416):
U.S. wheat germplasm is currently being tested for wheat blast resistance in BSL-3 greenhouses and growth chambers at ARS Fort Detrick, MD and at the Bio-Security Research Institute, at Kansas State University. Germplasm showing less than 10 percent infection from these replicated inoculations will be sent to CAPECO for field evaluation. Winter wheat entries will be sent to Paraguay for 6-8 weeks of artificial vernalization, then transplanted to the field using a replicated, randomized hill-plot design. Spring-habit wheat will be sent for planting without vernalization. Results obtained from both greenhouse and field evaluations will be passed back to U.S. breeders for evaluation and development of new germplasm. Testing of potential new sources of resistance will be evaluated in both the greenhouse and through field screenings. New isolates of M. oryzae collected from wheat and wild grass sources in Paraguay will be used in the development and confirmation of new molecular diagnostics and detection methods.
Field plots have been established and the irrigation system at the research site upgraded to accommodate wheat blast nursery and germplasm screening trials. Import permits of seed of wheat lines for germplasm screening trials have been submitted to the Paraguayan National Quality and Plant Health and Seeds for approval.