Assessment of genetic variation among wild Alpinia nigra (Zingiberaceae) population: an approach based on molecular phylogeny.

Abstract

Genetic structure was evaluated among wild Alpinia nigra (Gaertn.) B.L. Burtt, populations. The information of genetic relatedness was developed using random amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR) and barcoding loci (plastid and mitochondrial). The order (high to low) of Shannon's information index (I) and Nei's gene diversity (h) from the populations was: "IIT Guwahati" > "Amingaon" > "Saraighat". Genetic diversity decreased and genetic differentiation increased among the three populations. We observed no isolation by distance thus lower amount of gene flow was observed. Narrow range of genetic distance among the three populations and appearance of two distinct clusters strengthened the geographical isolation in dendrogram and principal component analysis. No mutation among the three populations was observed for seven plastid loci and two mitochondrial tested suggesting the taxonomic homogeneity. The phylogeny based on nine barcoding loci supported our observation that individuals of IIT Guwahati were partially isolated from the outside populations. Our study will provide a backbone for developing strategies to resist habitat fragmentation of Zingiberaceous plants.