SNP-based functional marker for anthracnose-resistant Co-2 gene in common bean (Phaseolus vulgaris L.)

Chainika Gupta, Romesh K. Salgotra y Raul Álvarez Venegas

Te invitamos a leer el artículo "SNP-based functional marker for anthracnose-resistant Co-2 gene in common bean (Phaseolus vulgaris L.)" publicado en "Journal of Plant Diseases and Protection" en el que colaboro el Dr. Raúl Álvarez Venegas de Cinvestav Irapuato.

Autores:

Chainika Gupta, Romesh K. Salgotra y Raul Álvarez Venegas 

Resumen:
     Functional markers (FMs) derived from polymorphic regions in Co-2 gene sequences influencing Colletotrichum lindemuthianum variation are very effective for transferring anthracnose resistance from highly resistant genotypes into susceptible cultivars of common bean through molecular breeding approaches. Single dominant gene Co-2 confers broad-spectrum resistance against Colletotrichum lindemuthianum, one of the most devastating disease-causing pathogens in common beans resulting in catastrophic yield loss. We report a SNP-based functional marker from the promoter region of the Co-2 gene which evokes a durable resistance against the anthracnose disease in common bean crop. In the study, the promoter regions of the genes of anthracnose-susceptible and anthracnose-resistant genotypes were characterized, cloned and sequenced. Out of 23 SNPs identified within the regulatory motifs of the promoter region, 14 exhibited a strong association with disease resistance. The allele-specific CAPS marker was developed and validated in common bean genotypes which showed varied levels of anthracnose resistance. A perfect correlation was observed between the developed CAPS marker and anthracnose resistance genotypes. Allele-specific marker was derived from polymorphic region in promoter sequence of a gene influencing phenotypic variation. This marker targets the resistance gene for developing host plant resistance and thereby can be utilized in molecular breeding programmes where anthracnose is a common problem. The identified allelic marker can be used for transferring anthracnose resistance from highly resistant genotypes into susceptible cultivated varieties of common beans using marker-assisted selection approach.