Analysis of Genetic Diversity in Wild Populations of Mulberry from Western Part of Northeast China Determined by ISSR Markers

Evaluating genetic diversity in mulberry consitutes an indespensible part in the use for taxonomical grouping and utilization in breeding and conservation programs. In this paper, population structure and genetic diversity of 2 populations of M. mongolica from Xianghai National Natural Reserve and Tongfa pastureland in Baicheng city, northeast China's Jilin province, were analyzed by ISSR markers. Eleven ISSR primers generated a total of 80 amplification products, of which 60 were polymorphic, revealing 75.00% polymorphism among 20 wild mulberry accessions. Mean Nei's gene diversity (h), mean Shannon's Information index (I), total heterozygosity (H(subscript T)), heterozygosity within population (H(subscript S)), and the diversity between populations (D(subscript ST)) were 0.2045, 0.3193, 0.1908, 0.1373, 0.0635, respectively. The coefficient of population differentiation (G(subscript ST)) was 0.2802, indicating that the genetic variation between populations was lower than the variations within populations. The genetic similarity coefficient among 20 mulberry materials ranged from 0.9750 to 0.5500, indicating that genetic diversity among different populations was imbedded with variation. Both UPGMA cluster and PCA analysis showed clear genetic relationships among the 20 mulberry individuals. The clusters were related to geographic origins.