Reaction of some cowpea genotypes (Vigna sinensis) to Bean common mosaic virus under greenhouse condition

Bean common mosaic virus is widely spread in the world, and also causes functional impairment in the quality of the product. Using tolerant and resistant genotypes is one of the main approaches to the management of this disease. For this purpose, the present study was conducted in two separate sections. 20 cowpea genotypes were studied in two separate experiments, with and without infection in a randomized complete block design, with three replications in greenhouse. The infection was conducted in 2-leaf phase by mechanical inoculation and morphological evaluation was recorded 21 days after infection. ELISA test was used to determine the infection rate of genotypes. Infection of cowpea genotypes were also checked by RT-PCR test using specific BCMV primers. Results suggest amplified fragment with length of 373 bp in the infected plants. The infection rate of different genotypes was 66.6 to 80%. According to the symptoms caused by mechanical inoculation with BCMV to cowpea genotypes was scored between 0-4 which used to obtain disease severity. According the all results, the genotypes divided to hypersensitive, sensitive, semi-resistant and resistant group.