1a.Objectives (from AD-416)
The objectives of this cooperative research are:. 1)develop and test wheat lines with resistance to KB; and. 2)develop and test molecular markers for resistance to KB.
1b.Approach (from AD-416)
Wheat experimental lines have been developed by crossing adapted varieties with different sources of resistance to KB. Wheat lines will be tested for resistance to KB in the field in India. Genetic mapping populations and near isogenic lines will be developed to identify and validate molecular markers for KB resistance genes. Molecular marker genotyping will be done in India and the USA. Data will be analyzed cooperatively.
Winter wheats were inoculated with sporidial suspensions derived from a mixture of isolates of the Karnal Bunt pathogen (Tilletia indica) by the syringe inoculation method under natural field conditions in Ludhiana, Punjab, India. The 4th, 5th, 6th, and 7th Winter Wheat Karnal Bunt Screening Nurseries (WWKBSN) were vernalized and planted. All the lines could be inoculated at the appropriate stage, i.e. at awn emergence. Frequent irrigation was carried out to maintain adequate humidity for disease development.
Many lines that showed resistance in previous years again showed moderate to good resistance. A set of progeny from the cross between HD29 (resistant Indian spring wheat variety) and Jagger (susceptible Kansas winter wheat variety) showed many individual with good resistance. Likewise, a cross between a resistant synthetic spring wheat and Karl 92 (susceptible Kansas winter type) continued to show moderate resistance. A new doubled haploid mapping population between a source of very high resistance and a susceptible line was evaluated for the second year. Disease incidence was low and thus the test will need to be repeated next year.
Progress on this agreement is monitored by regularly discussing program goals, approaches, and results (teleconference, email) and by reviewing annual accomplishments reports.