Genetic diversity and structure of Betula utilis accessions of North-western Himalaya based on RAPD and ISSR markers

Abstract

Betula utilis, commonly known as Himalayan birch is an important tree species of fragile ecosystem of Himalayas placed in endangered category. In the present study genetic diversity, structure and interrelationships of B. utilis accessions from North-western Himalayan regions were analyzed using Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) markers. 15 RAPD and 16 ISSR primers collectively amplified 109 polymorphic fragments with an average of 3.51 fragments in a size range of 300–1300 bp. Polymorphism Information Content (PIC) ranged from 0.21 to 0.5 with an average of 0.43. Dendrogram grouped all the accessions into two major clusters. Factorial analysis showed three groups for all the analyzed accessions. Bayesian clustering using STRUCTURE grouped all the accessions in two clusters and separated majority of accessions belonging to Jammu & Kashmir Himalaya (cluster-II) from other accessions of Himachal Pradesh and Uttarakhand Himalaya (cluster-I). Exceptionally, four accessions namely, Sinth-12, Sinth-20, Son-06 and Son-16 from Kashmir grouped in Cluster-I. Structure analysis showed that two genetic stocks were contributing in genetic makeup of all the analyzed accessions. Results of the present study can be useful for selection of diverse accessions as well as can be useful in designing conservation and management strategies in North-western Himalayan regions.