RAPD Analysis in Cowpea [Vigna ungaiculata (L.) WALP]

The present investigation was carried out with 18 germplasm of cowpea. Purified and isolated DNA was subjected to PCR based marker (RAPD) for assessment of genetic diversity. The quality of DNA was determined by calculating ratio between A260 and A28o. The ratio between A260 and A280 was observed 1.41-2.01 which indicated a moderately good quality of plant DNA. The concentration of DNA ranged from 3.12mg/ml to 3.92 mg/ml in RAPD analysis. PCR (RAPD) involving 15 randomly selected decamer primers, of which only 9 primers gave good amplified product with template DNA. A total of 204 amplified fragments were formed by 9 primers. A total of 48 amplicon were obtained with 9 primers with an average of 3.2 bands per primer. Out of 48 scorable bands, all 48 bends were polymorphic and the level of polymorphism was 100 per cent. From RAPD profiling similarty matrix was obtained and similarity coefficient ranged between 0.00 - 0.47. The dendrogram clearly divided the 18 cultivars into 5 main clusters. Cluster I includes 13 genotypes of cow pea and cluster II includes only one cultivar. Cluster III includes 2 genotypes. Cluster IV and V includes 1 genotype each. On this basis of similarty matrix, dendrogram was constructed using UPGMA method.