2009 Annual Report 1a.Objectives (from AD-416) The objectives of this cooperative research project are to: a) evaluate sorghum germplasm in several locations in Mexico for resistance to anthracnose, grain mold, head smut, and downy mildew; and b) determine the races of head smut, anthracnose, and downy mildew pathogens in the region. 1b.Approach (from AD-416) Exotic and adapted sorghum accessions will be planted in several locations in Mexico and evaluated for disease reaction. Standard sets of sorghum differentials will be provided by the ARS cooperator to identify the pathotypes of anthracnose, head smut, and downy mildew in Mexico. These sets of differentials will be open ended. Data will be analyzed and comparison among the accessions based on maturity groupings and other agronomic traits will be recorded. 3.Progress Report The goal of this project is to identify new resistance sources to important fungal diseases of sorghum in the U.S. and Mexico. In FY 2009, sorghum accessions from Mali, Sudan, and Uganda were planted in Celaya, Guanajuato (central portion of Mexico) for assessment of resistance against Exserohilum turcicum (causal agent of leaf blight) and Puccinia purpurea (causal agent of rust). Accessions PI 610020, PI 610003, PI 585731, PI 585727, and PI 525695 from Mali; PI 584304, PI 584286, PI 584255, and PI 584251 from Uganda; and PI 571388 from Sudan were highly resistant to leaf blight. PI 609934 and PI 582727 from Mali and PI 563220 from Uganda demonstrated significant resistance to rust infection. This work will be of benefit to sorghum breeders in their ongoing efforts to develop more disease-resistant sorghums for use by farmers in the U.S. and other nations, particularly Mexico. The ADODR of this project and the cooperator maintain regular communications by phone and e-mail, where progress of the work is assessed and where solutions to work impediments are developed. The ADODR and the cooperator meet periodically (at scientific meetings, annual visits to experimental sites, etc.), where the work is discussed and evaluated.