|Mutlu, N - UNIV OF NEBRASKA|
|Reiser, J - UNIV OF NEBRASKA|
|Coyne, D - UNIV OF NEBRASKA|
Submitted to: Plant Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 30, 2004
Publication Date: May 5, 2005
Citation: Mutlu, N., Miklas, P.N., Reiser, J., Coyne, D. 2005. Backcross breeding for improved resistance to common bacterial blight in pinto bean. Plant Breeding. 124:282-287. Interpretive Summary: Common bacterial blight is a major disease of dry edible (pinto, kidney, etc.) and snap (garden) bean. The disease is widespread in the Midwest bean production region ranging from ND to KS and CO to MI. Development of genetic resistance within the plant is the most effective prescription for control of this disease. ARS (Prosser, WA) and University of Nebraska researchers showed that the combination of a traditional breeding method 'backcrossing' with a new plant breeding technology 'DNA marker assisted selection' was effective for developing pinto beans with improved resistance to common bacterial blight disease. Pinto bean is the number one market class of dry edible beans grown in the U.S., and the Midwest represents the major production region for pinto beans. The resistant pinto beans developed in this study and the means described for obtaining them will lead to reduced yield loss from this disease, potentially adding income to Midwest bean farmers.
Technical Abstract: Common bacterial blight (CBB) reduces common bean (Phaseolus vulgaris L.) yield and quality. Genetic resistance provides effective disease control; however, a high level of resistance is difficult to attain and does not exist in pinto bean, the most important dry bean market class in North America. Our objective was to determine if a backcross approach could be used to obtain pinto bean with a high level of CBB resistance. Quantitative trait loci (QTL) conditioning CBB resistance from the donor parent XAN 159 were introgressed into the recurrent parent 'Chase' using classical backcross (BC) breeding and intermittent marker-assisted selection (MAS). DNA marker assays confirmed the presence of independent QTL from GN#1 Sel 27 and XAN 159 in advanced BC-derived pinto bean lines with improved CBB resistance. Agronomic characteristics of Chase were fully recovered in the BC-derived lines. An important QTL for CBB resistance from XAN 159 on linkage group B6 was not introgressed, because tight linkage between this QTL and the dominant V allele that causes an unacceptable black-mottled seed coat color pattern in pinto bean could not be broken.