|Miklas, Phillip - Phil|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/20/2005
Publication Date: 1/25/2006
Citation: Miklas, P.N., Kelly, J.D., Beebe, S.E., Blair, M.W. 2006. Euphytica: invited review paper for special 2005 issue. common bean breeding for resistance against biotic and abiotic stresses: from classical to mas breeding. Euphytica. 147:106-131. Interpretive Summary: Biotic (diseases and insects) and abiotic (low soil fertility, drought, etc.) stresses reduce dry bean yields worldwide. Sustainable farmers in poorer countries are severely affected by such stresses because they are less able to afford inputs to correct fertility problems and protect crops from insect pests and diseases. Genetic stress resistance within the host provides an affordable and safe means to alleviate pest and fertility problems. This paper reviews efforts to breed beans with improved stress resistance and highlights the use of DNA markers as tools for indirect selection and manipulation of resistance traits. This review will be a helpful guide to bean breeders across the world by providing descriptions of new resistance genes and germplasm sources and new and innovative breeding strategies for combating numerous biotic and abiotic stresses. Specific problems addressed include diseases like angular leaf spot, anthracnose, bean common mosaic virus, beet curly top virus, bean golden yellow mosaic virus, common bacterial blight, halo bacterial blight, rust, root rot, and white mold, insect pests such as bean pod weevil, bruchid seed weevils, leafhopper, thrips, bean fly, and whitefly, and abiotic stresses caused by drought, low soil phosphorus, and poor symbiotic nitrogen fixation. The research described will lead to development of new bean cultivars and germplasm lines around the world with improved stress resistance which will improve farmer income and reduce food shortages, in addition to contributing to a safer environment from reduced chemical use.
Technical Abstract: Breeding for resistance to biotic and abiotic stresses of global importance in common bean is reviewed with emphasis on development and application of marker-assisted selection (MAS). The implementation and adoption of MAS in breeding for disease resistance is advanced compared to insect and abiotic stress resistance, and reveals in general the role and success of MAS in gene pyramiding, retaining defeated resistance genes, rapidly deploying resistance genes via marker-assisted backcrossing, enabling simpler detection and selection of resistance genes in absence of the pathogen, and contributing to simplified breeding of complex traits by detection and indirect selection of quantitative trait loci (QTL) with major effects. The current status of MAS in breeding for resistance to angular leaf spot, anthracnose, Bean common mosaic and Bean common mosaic necrosis viruses, Beet curly top virus, Bean golden yellow mosaic virus, common bacterial blight, halo bacterial blight, rust, root rots, and white mold is reviewed in detail. Cumulative mapping of disease resistance traits has revealed new resistance gene clusters while adding to others, and reinforces the co-location of QTL conditioning resistance with specific resistance genes and defense-related genes. Breeding for resistance to insect pests is updated for bean pod weevil (Apion), bruchid seed weevils, leafhopper, thrips, bean fly, and whitefly, and includes use of arcelin proteins as selectable markers for resistance to bruchid seed weevils. Breeding for resistance to abiotic stresses concentrates on drought, low soil phosphorus, and improved symbiotic nitrogen fixation. The combination of root growth and morphology traits, phosphorus uptake mechanisms, root acid exudation, and other traits in alleviating phosphorus deficiency, and identification of numerous QTL of relatively minor effect associated with each trait, reveals the complexity to be addressed in breeding for abiotic stress resistance in common bean.