MOLECULAR DIVERSITY ANALYSIS OF SOMACLONAL VARIANTS IN POTATO (Solanum tuberosum L.) BY RAPD MARKERMD SHAMSUZZAMAN

Abstract

An experiment was carried out in Biotechnology Laboratory of the Department of Biotechnology, Sher-e-Bangla Agricultural University (SAU), Dhaka, Bangladesh to study the DNA fingerprinting and genetic diversity of nine somaclonal variants of potato (Solanum tuberosum L.) and three check varieties (Cardinal, Diamant and Asterix). The somaclonal variants were SIP-3, SIP-5, SVP-6, SVP-18, SVP-19, SVP-25, SVP-55, SVP-56 and SVP-68. Genomic DNA was extracted from young leaves and PCR reaction was performed with six RAPD primers. Sum total of 54 distinct and differential amplified DNA bands were generated from PCR amplification. Out of them, 47 bands (87.04%) were polymorphic and 7 bands (12.96%) were monomorphic. The pair wise inter-variety/genotype similarity indices ranged from 61.59% to 93.55% with an average of 74.31%. The Nei’s genetic identity among 12 potato genotypes ranged from 0.5370 to 0.9074 and genetic distance ranged from 0.0972 to 0.6217. The UPGMA Dendrogram segregated the 12 potato genotypes into two main clusters. The first cluster contained 8 genotypes and the second cluster had 4 genotypes. The Dendrogram also indicated the highest genetic distance and the lowest genetic identity between SVP-6 vs SVP-68 genotype pair. The study revealed a significant amount of relationship and genetic diversity among the studied 12 potato genotypes. The RAPD markers were found to be useful tool for DNA fingerprinting, polymorphic study and genetic diversity analysis of potato genotypes with a great potential for the Bio technologists and Plant breeders for the improvement of potato cultivars