|Blair, M - ARC GRAIN CROPS,S.AFRICA|
|Fourie, D - CIAT, COLOMBIA|
Submitted to: World Cowpea Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 1, 2004
Publication Date: April 1, 2005
Citation: Miklas, P.N., Blair, M.W., Fourie, D. 2005. Marker aided breeding for resistance to common bacterial blight in common bean. Proceedings of 1st International Edible Legume Conference and 4th World Cowpea Congress, Durban, South Africa, April 17-21, 2005. p. 11. Technical Abstract: Common bacterial blight caused by Xanthomonas axonopodis pv. phaseoli is a serious seedborne disease limiting common bean production worldwide. Genetic resistance is the most important component of integrated strategies including planting pathogen-free seed, crop rotation, and chemical applications, used to control the disease. Breeding for resistance is difficult because it is quantitatively inherited, influenced by environment, and different genes influence resistance in different plant organs (leaves, pods, and seeds). The objective of this research is to review classical breeding and MAS for resistance to common bacterial blight in common bean. Resistance sources are well characterized but not widely deployed in commercial bean market classes worldwide. Many QTL have been identified that influence resistance to CBB, but the majority have minor-effect and do not express in multiple environments or genetic backgrounds. SCAR markers linked with three QTL of major effect are available. The three QTL derive from two sources XAN 159 and Montana No. 5. The SCARs have been used for MAS to develop breeding lines and cultivars with improved CBB resistance. The markers have also been used to ascertain resistance gene (QTL) deployment in cultivars bred specifically for resistance to common bacterial blight using conventional means. Cumulative results from the literature and our own research indicate that MAS combined with intermittent pathogen screening is an effective strategy for developing common bean with resistance to common bacterial blight.