Abstract: By the method of microsatellite analysis, an investigation was conducted on the genetic diversity of 15 wild populations of oriental river prawn(Macrobrachium nipponense) in Poyang Lake. The 10 microsatellite loci were highly polymorphic, and a total of 129 alleles were detected. The tests of departure from Hardy-Weinberg equilibrium indicated that at least 5 loci for each population were in significant heterozygosity deficiency. For all the populations, there existed significant deviation from Hardy-Weinberg equilibrium. The 15 populations all showed high genetic diversity; the genetic diversity in Dabawai and Xinchi populations was relatively higher compared with the Wanhu and Hukou populations. Bottleneck effect and mutation-drift equilibrium tests indicated that the M.nipponense populations in the Lake did not suffer bottleneck effect, and had no decline in their quantity in recent time. The F_ST and AMOVA analysis across all the populations suggested that there was a significant genetic differentiation among the 15 populations (F_ST=0.04709, P<0.01). This study showed that the M.nipponense populations in Poyang Lake had high genetic diversity, with greater potential for breeding.

Key words: Qiandao Lake, Chlorophyll a, Multiple stepwise regression, Trophic state index