SSR Marker Exploitation And Molecular Mapping Of Anthracnose Resistant Gene In Common Bean (Phaseolus Vulgaris L.)

Anthracnose, caused by the fungus Colletotrichum lindemuthianum (Sacc. and Magnus) Briosi and Cavara, is one of the most widespread and serious disease of common bean (Phaseolus vulgaris L). Due to its seed-borne nature and the pathogenic variability of Colletotrichum lindemuthianum, it caused severe economic losses in tropical, subtropical, and even temperate areas when favorable conditions for the fungus were present during the growing season. Utilizing resistant cultivars is the most effective, economic and environmental method for controling this disease. To detect resistance gene by using tightly linked molecular makers has been turned into a rapid and effective way for molecular maker assiatant breeding. Many molecular makers, such as AFLP, RAPD, SSR and CAPs are used in the research of common bean. However, it is far from enough to the need of common bean breeding. It is necessary to develop more molecular makers.In this study, we constructed several hybridized combination. 7389 pairs of SSR primers were designed based on genome DNA sequencing and 1000 were tested for polymorphism between the Red bean and Jing bean. We also dissected the genetic pattern of resistance to anthracnose race (81) in Red bean. At last, we detect gene resistance to anthracnose by Bulked Segregant Analysis (BSA) and microsatallite polymorphism. The results are as follows:1. The F2 populations from the Red bean×Jing bean, Red bean×Michelite, paddy bean×Jing bean and F2:3 families derived from the cross between the Red bean×Jing bean were gotten in this study.2. A total of 1335 SSR primers were used to evaluate their polymorphism between Red bean and Jing bean, and approximately 119 polymorphic markers were found between the parents. These 119 SSR primer pairs were examined on the two bulked DNA pools from the extremes of resistant to anthracnose, and four markers showed polymorphism between the R and S DNA pools..3. A new genetic linkage map was constructed using 140 makers (138 SSRs and 2 CAPs), incluing 12 linkage groups. Total map length was 2878.63cM and the average distance between two makers is 20.56 cM.4. It was observed that Red bean carried a single dominant gene for resistance to the 81 race of anthracnose, designated Co-F2322 tentatively.5. The anthracnose gene was mapped on linkage group B1 by means of polymorphic analysis of mictosatellite makers and genetic linkage map. Six SSR markers (BMc32, C180, C871, C171, C16,Pvm98) and two CAPs makers (g1224, g683 ) were detected linking to the resistance gene with the distance of 26.14cM, 15.60cM, 3.58cM, 4.97cM, 12.15cM, 13.8cM, 3.81cM and 12.99cM respectively. The position of the makers linked to the resiatance gene on chromosome was BMc32-C180-g1224-Co-F2322 ?C871-C171-C16-g683-Pvm97.6. We presumed that Co-F2322 is an allelic gene of Co-1.