|Miklas, Phillip - Phil|
Submitted to: Field Crops Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/1/2002
Publication Date: 5/1/2003
Citation: KELLY, J.D., GEPTS, P., MIKLAS, P.N., COYNE, D.P. TAGGING AND MAPPING OF GENES AND QTL AND MOLECULAR MARKER-ASSISTED SELECTION FOR TRAITS OF ECONOMIC IMPORTANCE IN BEAN AND COWPEA. FIELD CROPS RESEARCH, 82:135-154. 2003. Interpretive Summary: The Bean/Cowpea Collaborative Research Support Program is a US-AID project that has targeted bean and cowpea improvement in Africa, and bean improvement in Central America, South America, and Caribbean countries for over 20 years. This paper reviews gene tagging and mapping research conducted by the project's scientists and cooperators. Defense genes and phenotypic traits for disease and insect resistance, seed size, color and storage proteins, pod color and those traits associated with the domestication syndrome in bean have been mapped. This work has progressed to a point where major resistance gene clusters have been revealed on linkage groups B1, B4, B7, and B11. The bean map provides a blueprint for conducting indirect selection for resistance to a number of major diseases in the U.S. and overseas, and in fact, recent ARS bean germplasm releases with anthracnose resistance were developed solely by marker-assisted selection. As more information is generated and integrated into the maps, its benefit to breeders and other users increases exponentially.
Technical Abstract: Bean/Cowpea Collaborative Research Support Program (B/C CRSP) scientists have successfully integrated consensus maps of the 11 linkage groups in both bean (Phaseolus vulgaris L.) and cowpea (Vigna unguiculata). The bean map is approximately 1200 cM with some 500 markers and an additional 500 markers shared with other bean maps. In contrast the cowpea map spans 2670 cM with over 400 markers. In addition to markers, both maps include map locations of defense genes and phenotypic traits for disease and insect resistance, seed size, color and storage proteins, pod color and those traits associated with the domestication syndrome in bean. Since the bean and cowpea maps were developed independently, linkage groups with the same number probably refer to non-syntenic groups. Map locations of major resistance genes in bean are revealing gene clusters on linkage groups B1, B4, B7, and B11 for resistance to bean rust, anthracnose, common bacterial blight and white mold. Gene tagging and marker assisted selection for disease resistance has progressed to a point where the indirect selection for resistance to a number of major diseases is now routine in bean breeding programs both in the U.S. and overseas.