New insights to protection and utilization of silver carp (Hypophthalmichthys molitrix) in Yangtze River based on microsatellite analysis

Abstract In the present study, fourteen highly polymorphic microsatellite markers were used to analyze genetic diversity and population structure of six populations of silver carp in the middle and lower Yangtze River basin. The results showed that the polymorphic information content (PIC) of these fourteen loci was between 0.306−0.848, 9 of 14 loci were highly polymorphic (PIC > 0.5). The allele number (Na) of the 6 populations was between 5–18, and the effective allele number (Ne) ranged from 1.5628 to 7.2676. The observed heterozygosity and expected heterozygosity were ranged from 0.287 to 0.753, and from 0.361 to 0.865, respectively. The average polymorphism information content was between 0.306 to 0.848. The Jianli, Changsha and Jiaxing population showed relatively high genetic diversity in all six populations(PIC > 0.5). The genetic distance between the Jianli and Hanjiang was the highest, while Ruichang and Jiaxing with the lowest genetic distance. The phylogenetic relation results showed the six populations were clustered into two clades, which indicated that there were differentiated in certain degree among the middle and lower populations in Yangtze river basin and the populations of this research may belong to different spawning grounds. In next enhancement and releasing, the germplasm resources of silver carp should be selected from corresponding regions.