Assessment of genetic diversity and differentiation ofElymus nutansindigenous to Qinghai–Tibet Plateau using simple sequence repeats markers

Abstract

Chen, S., Zhang, X., Ma, X. and Huang, L. 2013. Assessment of genetic diversity and differentiation of Elymus nutans indigenous to Qinghai–Tibet Plateau using simple sequence repeats markers. Can. J. Plant Sci. 93: 1089–1096. Elymus nutans Griseb., an important alpine forage grass, is widely distributed in the Qinghai–Tibet Plateau. A total of 50 E. nutans accessions from the eastern Qinghai–Tibet Plateau were analyzed using simple sequence repeats (SSR) markers from wheat and Elymus species. Our results show that a total of 144 reliable bands were generated, of which 132 (91.38%) were found to be polymorphic. Nei-Li's genetic similarity coefficients ranged from 0.515 to 0.870 with an average of 0.719, which shows a high level of genetic diversity and a broad genetic base among accessions. There was a low correlation between genetic distance and geographical distance (r=0.121, P=0.088) in the region, which is consistent with the unweighted pair group method with arithmetic average cluster analysis of accessions. The mountain ridges and river valleys in the eastern Qinghai–Tibet region could serve as genetic barriers for pollinator movement and seed dispersal. The rule of the most genetic diversity at medium altitude of E. nutans in the Qinghai–Tibet Plateau was also validated in the study. The implications of these results for the conservation of E. nutans are discussed.