ISSR and ITS analyses to assess genetic diversity and phylogeny to conserve an endemic and critically endangered tree, Memecylon subcordatum, in India

Memecylon subcordatum (Melastomataceae) is an endemic and critically endangered species of the Kalakkad-Mundanthurai Tiger Reserve in India. Twenty five inter-simple sequence repeat primers were used to screen 86 individuals. Nine primers produced a total of 61 bands (6.77 bands primer−1) ranging from 200 to 1900 bp wherein 48 bands were of polymorphic. Polymorphism was 78.69% within the species, 26.60% within the populations and 7.41%–48.15% among the populations. Genetic variation varied from 0.3069 (within species) to 0.1182 (within populations). The poor gene flow among the populations (Nm: 0.3133) could be due to the genetic barriers caused by the tributaries of Tambraparani river. The coefficient of genetic differentiation between the populations (GST) was 0.6148. The Bayesian analysis, multidimensional scaling analysis and principal coordinates analysis grouped all the 11 populations under 4 clades. The Mantel test showed significant correlation between the matrices of genetic and geographic distances (r = 0.652, P