2009 Annual Report 1a.Objectives (from AD-416) The objectives of this cooperative research project are: . 1)Organize and coordinate the Winter Wheat Karnal Bunt (KB) Screening Nursery (WWKBSN) in collaboration with CIMMYT and PAU;. 2)Obtain, increase, and distribute new KB-resistant wheat germplasm lines to regional breeding programs; and. 3)Make crosses between known KB-resistant germplasm lines and elite adapted winter wheat materials from regional wheat breeding programs;. 4)Select adapted KB-resistant lines for germplasm release and cultivar development. 1b.Approach (from AD-416) Resistant varieties are an important component of an integrated strategy to control KB. The use of resistant varieties is the most economical, sustainable, and long lasting means of control. Dedicated KB screening nurseries exist in collaborating research programs at CIMMYT in Mexico and Punjab Agricultural University (PAU) in India. These nurseries will be used to test experimental wheat breeding lines and mapping populations from the USA for resistance to KB. Known KB-resistant spring wheat lines will be obtained and crossed with locally adapted varieties. Resulting lines will be tested for resistance in the KB nurseries. Field selection will be done at multiple locations for agronomic type. 3.Progress Report The Seventh Winter Wheat Karnal Bunt Screening Nursery (WWKBSN) was prepared in August, 2008 from entries received from various winter wheat breeding programs. It was sent for evaluation to CIMMYT in Mexico and to Punjab Agricultural University (PAU) in India, and cooperators at each organization artificially inoculated each entry with Karnal Bunt in early spring, 2009. Selected entries with low disease levels from previous nurseries were also retested by cooperators. A few materials with consistently good levels of KB resistance have been identified through the cooperative screening of the WWKBSN at CIMMYT and in India. The most promising materials are several sister lines from the cross MASON/JAGGER//PECOS (TX99M5009) that have consistently given very low levels of infection, and these lines will be released by Texas A & M University in the near future as “germplasm for KB resistance”. Several additional materials have consistently given low KB readings including some backcross lines with the cultivar Jagger and some synthetic-derived lines. None of these materials have shown immunity, but their level of resistance to KB is probably sufficient to give protection at the field level. In the Eighth WWKBSN that will be assembled in August, 2009, most of the entries from the HRWW region will be advanced breeding lines derived from populations made for KB resistance under this program. In the OSU breeding program, populations at the F1 to F8 levels will be evaluated during the 2009-2010 crop season. These materials will be evaluated for leaf and stripe rust resistance, tolerance to abiotic stresses, adaptation, and agronomic type during the 2009-2010 crop year in southern Texas (Castroville nursery) and in Oklahoma. Lines with good agronomic type will be tested in the F5 generation or above in the WWKBSN. The ultimate objective is to identify well adapted winter wheat cultivars for our producers that have adequate levels of KB resistance to provide protection against infection. Progress on this agreement is monitored by regularly discussing program goals, approaches, and results (teleconference, email) and by reviewing annual accomplishments reports.