Potential of start codon targeted (SCoT) markers for assessment of genetic diversity of arecanut (Areca catechu L.)

Abstract

Gene-targeted markers constitute recent and novel marker systems, which are based on polymorphic sites existing within gene targeting regions. One among these marker systems is the Start Codon Targeted (SCoT), which is based on the short conserved region of plant genes, which neighbours the ATG start codon. SCoT markers, by virtue of both their higher length of the primers and annealing temperatures, are generally reproducible and have been reported to be highly polymorphic, compared to other dominant markers. In this study, analysis of genetic diversity among six arecanut accessions, viz., Mangala, Sumangala, Sreemangala, Mohitnagar, Swarnamangala and a natural dwarf mutant (Hirehalli Dwarf) was carried out using SCoT markers to evaluate the applicability of these markers in genetic diversity studies in arecanut. Using 10 SCoT primers, 82 band were produced among the accessions, of which 58 (70.73%) were found to be polymorphic. The highest genetic similarity value of 0.89 was found between the Swarnamangala and Mohitnagar and the lowest value of 0.63 was noticed between the Hirehalli Dwarf and Mohitnagar. The similarity coefficient values were then utilized to construct a dendrogram utilizing the unweighted pair group of arithmetic means (UPGMA). The cultivars were grouped depending on their geographical origins. The results obtained in this study indicate the suitability of SCoT marker system for genetic diversity analysis in arecanut.