Development and characterization of genomic microsatellite markers in Melia azedarach

Abstract

Melia azedarach is ecologically imperative species known for its innumerable biological benefits such as antiviral, anthelminthic, antibacterial, etc. In this study, we developed 43 genomic microsatellite markers from (AG)n enriched library and subsequently employed 23 of them for genetic diversity and population structure analysis of Melia azedarach growing in Indian Thar desert. Fourteen populations encompassing 95 genotypes were selected for analysis and we found a moderate level of diversity (Na = 3.211, Ho = 0.558, He = 0.549, P = 94.41%) in them. Gene diversity (h) among population pairs varied from 0.566 to 0.714 with very low overall genetic differentiation (F = 0.021). The highest value of ΔK estimated using STRUCTURE indicated 2 subpopulations (K=2) and admixed cluster occupied maximum area (75.79%) under Bar plot. Genetic distance based UPGMA dendrogram also identified 2 major clusters among 14 Melia azedarach populations. UNJ tree based on genetic dissimilarity clustered genotypes from different population together. No significant correlation between geographical and genetic distance was found in present study (Rxy = 0.261, P = 0.18). Allele frequency distribution under “mode-shift” indicator was normal L-shaped, suggesting populations under study are not experiencing any recent bottleneck. This study laid the foundation for more precise inference about the biogeography and management of M. azedarach in the Indian Thar Desert