Location: Tropical Crops and Germplasm Research2009 Annual Report
1a. Objectives (from AD-416)
Utilization of untapped genetic diversity through the conversion of germplasm and the incorporation of key traits into common bean improvement programs for abiotic stress tolerance and disease resistance. Application of genetic analysis and TILLING (targeting induced local lesions in genomes) for identification and mapping of important traits in common bean. Development and release of improved germplasm for specific agriculturally important biotic and abiotic stress tolerance traits and identification of associated molecular markers.
1b. Approach (from AD-416)
Increase genetic diversity in common bean germplasm through conversion of specific abiotic and biotic traits from tropical germplasm. Elucidate the genetics of drought and heat tolerance, and other agriculturally important traits, using molecular markers, TILLING, and classical genetic approaches. Develop germplasm with improved disease resistance and abiotic stress tolerance through phenotypic selection and marker assisted selection.
3. Progress Report
Breeding lines in the conversion program are being advanced using the inbred backcross method or continued backcrossing. In addition, advanced lines with specific traits of interest are being tested in the US for photoperiod insensitivity and for the target trait. Trials are currently underway with these materials in Michigan, Nebraska, North Dakota, and New York. Six recombinant inbred line (RIL) populations were developed for the study of the genetics of drought tolerance in common bean in collaboration with the University of Nebraska. These populations are currently in the F4 generation. The current mutant population (>2,000 lines) was sent to two ARS labs in the US for evaluation of specific seed traits, while population development continues in Puerto Rico. The program is currently in the process of releasing a kidney bean germplasm line with heat tolerance. Generated advanced lines of BC3 and BC4 generation breeding lines with VAX 6 derived CBB resistance for potential release that are currently being tested in the US and Puerto Rico.
1. Release of a cultivar and a germplasm line with multiple stress tolerance. Participated in the release of the cultivar ‘Badillo,’ the first kidney cultivar with resistance to common bacterial blight, in addition to resistance to bean common mosaic virus and endemic races of rust.
Porch, T.G., Ramirez, V.H., Santana, D., Harmsen, E.W. 2009. Evaluation of drought tolerance in common bean germplasm in Juana Díaz, Puerto Rico. Journal of Agronomy and Crop Science 195:328-334.