Multiple genes confer anthracnose resistance in French bean accessions of Garhwal Himalayas

Abstract The Indian Himalayan region is very rich in the genetic variability of French bean and therefore considered as the secondary centre of origin of French bean. Though, a good diversity of French bean is present in Uttarakhand hills of Western Himalaya but it is almost unexplored yet. Unfortunately, French bean is attacked by some of the phytopathogens those cause heavy crop losses. Colletotrichum lindemuthianu (Sacc. & Magnus) Scrib is one of the sever pathogens that causes anthracnose disease in French bean worldwide. Identification or development of a resistant variety/cultivar is an environmentally safe approach. Diversity analysis of anthracnose resistant loci in common bean is important to identify new sources of resistance gene(s). So the study was designed with the objectives to collect and screen the local accessions of French bean from Garhwal hills for anthracnose resistance. A total of 100 accessions were collected from 6 different districts of Garhwal region of Uttarakhand and all were screened for anthracnose resistance. For this, 13 SCAR (Sequence cleaved amplified region) primers specific to anthracnose resistance were used in this study. Results revealed a high level of genetic diversity within the population for anthracnose resistance loci. Gene diversity ranged from 0.354 to 0.499 with a mean of 0.457. Pair wise genetic distance ranged from 0 to 2.236. The accessions were also screened for anthracnose resistance under field and polyhouse conditions. There was a moderate correlation (R = 0.56) between field trial and trial under controlled condition. Thirteen of these accessions possessing two genes (Co-10 and Co-42) showed complete resistance for anthracnose disease under field and polyhouse conditions. The anthracnose resistant accessions may further be used in future breeding programmes to develop new and more resistant varieties of French bean against anthracnose disease.