Location: Hard Winter Wheat Genetics Research Unit
2011 Annual Report
In order to produce commercially competitive varieties of the future, new stem rust resistance genes must be incorporated into a forward breeding program. In addition, a backcross breeding program is required both for parent-building and as a hedge if commercially acceptable resistant varieties are needed in the short term. Rapid breeding methods, such as doubled haploids, will be needed to achieve results as quickly as possible.
Phenotypic selection for resistance using common North American races will be difficult in most backgrounds due to the high frequency of endemic stem rust resistance genes. Therefore, marker-assisted selection for new resistance genes will be necessary. Molecular markers are available or under development for virtually all new sources of stem rust resistance. Marker genotypes will be generated locally or in a high throughput facility at the USDA-ARS Regional Small Grains Genotyping Laboratory in Manhattan, KS. Resistance of advanced lines against African races of stem rust will be confirmed by field testing at cooperative research facilities in Kenya or at the USDA-ARS Cereal Disease Laboratory. Testing for agronomic traits, yield, and quality will be performed as usual by the breeding program.
This progress report covers the first year of the cooperative Ug99 stem rust resistance breeding project between Colorado State University and ARS. A set of crosses were made between elite hard red or white winter wheat lines and donor lines that contained Sr22, Sr32, Sr35, Sr39, Sr40, or Sr26. Sr2 and Sr1A.1R stem rust resistance genes were also present in some parental lines. Marker-assisted selection will be used to track the genes as they segregate in the crosses.
Progress on this agreement is monitored by regularly discussing program goals and approaches in face-to-face meetings, by email and phone conferences, and by reviewing annual accomplishments reports.