Genetic Variation in Wild and Cultured Populations of the Freshwater Prawn, Macrobrachium nipponense, in China

Genetic diversities of five domestic and five wild populations of the freshwater prawn, Macrobrachium nipponense, in Jiangsu Province, China, were assessed by amplified fragment length polymorphism analysis. A total of 267 unambiguous polymorphic bands were detected from 300 individuals. The percentage of polymorphic bands varied from 33.64 to 55.14% in the 10 populations. The Nei genetic diversities of the wild populations and their domestic counterparts after several generations were 0.185 +/- 0.024 and 0.164 +/- 0.013, respectively, showing a decrease in genetic diversity in domestic populations. The largest genetic differentiation exists among the populations from different geographical locations, whereas there was less differentiation between the wild and domestic population in the same site. The cultured population in the north of Jiangsu Province where the large individuals of the prawns were harvested twice a year in spring and autumn for 4 yr almost had no change of genetic diversity (P > 0.05); whereas the cultured population in the south of Jiangsu where the large individuals were harvested all the year had a significantly reduced genetic diversity (P < 0.05). Therefore, we deduced that the aquaculture model in the north of Jiangsu should be better than that in the south. The results may be helpful to genetic enhancement and conservation programs of this species.