Genetic diversity analysis and EST-SSR fingerprinting construction of natural Populus euphratica and Populus pruinosa populations

Abstract

Abstract Populus euphratica and Populus pruinosa are important tree species in northwest China. In this study, the codominant EST-SSR markers related to drought resistance genes was used to reveal the genetic diversity of P. euphratica and P. pruinosa populations. The results showed that those populations exhibited rich genetic diversity levels. Compared with other P. euphratica and P. pruinosa populations respectively, the genetic diversity of populations in southern Xinjiang was all the highest. The average fixed index of different populations indicated that the genetic relationship among P. euphratica populations was relatively far, while the relationship among the P. pruinosa populations was closer. The molecular variance analysis showed that the variation within populations was bigger than that among populations in the P. euphratica and P. pruinosa populations respectively. The cluster analysis showed that P. euphratica and P. pruinosa populations could be mainly classified into two clades represented by southern and northern Xinjiang respectively. The population structure and principal co-ordinates analysis indicated that the 47 natural P. euphratica populations have been divided into 4 clades, represented by the two populations in southern or southern Xinjiang respectively. The 17 natural P. pruinosa populations had been divided into 4 clades, consisted by the three County in southern Xinjiang, and Nilka County in northern Xinjiang. At the same time, The EST-SSR fingerprintings of 47 natural Populus euphratica and 17 natural Populus pruinosa have been constructed successfully. This study laid the foundation for the later priority protection of the genetic diversity populations of excellent drought resistance.