Genetic relatedness in cashew (Anacardium occidentale L.) germplasm collections as determined by randomly amplified polymorphic DNA

Abstract

In the present investigation, we have assessed the genetic relationship of twenty varieties of cashew by using RAPD (Randomly Amplified Polymorphic DNA) markers. Analysis started by using forty 10-mer primers that allowed us to distinguish 20 varieties. The selected primers were used for identification of cashew varieties. A total of 80 distinct DNA fragments ranging from 0.2 to 3.0 Kb were amplified by using 11 selected random 10-mer primers. Genetic similarity analysis was conducted on the presence or absence of bands in the RAPD profile. Cluster analysis clearly showed that 20 varieties of cashew grouped into 2 major clusters based on similarity indices. First major cluster again divided into one minor cluster. Another major cluster again divided into two sub-minor clusters, one sub-minor cluster having three varieties and another sub-minor cluster represented by 15 varieties. Among the 20 varieties, ULLAL-3 and H-1608 showed highest similarity indices (87%). It was noted that ‘Vengrula-2’ and ‘Vengrula-3’ were not grouped into a single cluster but ‘Vengrula-4’ has 82% similarity with ‘Vengrula-3’. The variety Vengrula-2 has very close similarity (85%) with variety VRI-3. Analysis of genetic relationships in cashew using RAPD banding data may be useful for plant improvement, in descriptions of new variety and also assessing variety purity in plant certification programmes.