GENETIC DIVERSITY OF MELIA DUBIA USING ISSR MARKERS FOR NATURAL POPULATIONS AND PLANTATIONS

Melia dubia Cav. (Family: Meliaceae) is a deciduous tree species native to India. It is an important plantation species with short rotation and multipurpose uses, highly valued as a pulpwood and plywood. Genetic variation was assessed in eleven natural populations and seven plantations across eight districts of Karnataka comprising 232 samples through 15 ISSR markers. At species level, genetic diversity estimates viz., Percentage polymorphism (94.6), percentage of polymorphic loci (PPL) (98.8), observed number of alleles (Na=1.98), effective number of alleles (Ne= 1.59), Neis gene diversity (H) (0.34±0.15) and Shannons information index (I) (0.51±0.19) were found to be high. In individual populations H ranged from 0.10±0.19 to 0.32±0.18 and I ranged from 0.15±0.26 to 0.47±0.25. Among different natural populations, Bhadravati exhibited the highest level of variability while in plantations Hunsur had maximum variability. Analysis of Molecular Variance showed that much of the genetic variation resided within the populations (68%) than among populations. The dendrogram obtained by using Unweighted Pair- Group method with Arithmetic average did not reflect geographical sub clustering of genetic diversity except for few populations. Based on the genetic variability found, superior seed sources can be identified and tree improvement strategies could be developed for conservation and further improvement of the species