Analysis Of Genetic Diversity Of Macrobrachium Nipponense In Yellow River Basin

Macrobrachium nipponense, Oriental river prawn, is extensively distributed in China. It is an important freshwater aquaculture species in China. At present, large-scale production of Macrobrachium nipponense has been carried out in the middle-lower reaches of the Yangtze River. But in recent years, feral resource of Macrobrachium nipponense dramatically decreases with time passing due to overfishing and habitat changing. For the protection and sustainable development of Macrobrachium nipponense resources, it is necessary to study the genetic diversity in different rivers. The Yellow River is the second longest river in China, playing an important role in fishery in China. Thus, researches on genetic diversity of Macrobrachium nipponense in Yellow River have positive effects on protection and sustainable development of Macrobrachium nipponense germplasm resources. Microsatellite molecular markers were used to reveal the genetic diversity and genetic structure of7populations of Macrobrachium nipponense in the Yellow River basin. The main results are as follows:Twenty polymorphic microsatellite loci with clear strip were selected from37microsatellite loci to investigate the genetic diversity of7Macrobrachium nipponense populations in the Yellow River basin. The average number of alleles (A) and effective numbers of alleles (Ne) in7populations were4.2643and2.6682, respectively. The mean PIC value of20microsatellite loci was0.5575. Expected heterozygosities (He) of7populations were as the order from high to low:Sanmenxia (0.6146), Jinan (0.5735), Dongying (0.5701), Dongming (0.5626), Jiyuan(0.5440), Pianguan (0.5438) and Yinchuan (0.5174). Based on the analysis of molecular variance (AMOVA), the majority of the variance in the Macrobrachium nipponense was almost within populations (94%), and6%was among populations. The Fst values between populations were0.0172-0.0791(P<0.05), implying the genetic divergence between populations in the Yellow River was intermediate. The Fst value was lower than that in the lakes because running water possibly promotes the genetic exchanges between populations. Hardy-Weinberg equilibrium analysis indicated that deficiency of heterozygote existed in all7populations, which may be explained by rare allele deficiency or null alleles. The genetic distances among populations ranged from 0.0455to0.2223.The UPGMA tree showed that:Pianguan population and Yinchuan population are divided into the same class and other5populations formed another one in which Dongming population and Dongying population clustered at first.This study focused on the genetic diversity and genetic structure of Macrobrachium nipponense population in Yellow River using microsatellite molecular markers. The results provides background information for the Macrobrachium nipponense breeding work, as well as promoting the protection and sustainable development of Yellow River wild Macrobrachium nipponense.