Genetic diversity in Penaeus chinensis shrimp as revealed by RAPD technique

The random amplified polymorphic DNA analysis was used to estimate genetic diversity in one successively cultivated stock and three wild stocks of Penaeus chinensis shrimp, two of which were collected from the spawning and wintering grounds in the west coast of Korean Peninsula, and one from the feeding ground in the China coast of the Yellow Sea. A random primer kit was employed to scan the genomic DNA in 20 individuals of each index stock. A total of 110 reproducible RAPD markers were obtained, 68.2 % of which showed a sound eonformability within all the individuals detected, implying that the genetic variability in P. chinensis is relatively low. The proportions of polymorphic loci among these four stocks ranged from 20% to 33.3%, while the degrees of genetic polymorphisms varied from 0.0093 to 0.0307. The genetic variability of inter-stocks was higher than that of intra-stock. The genetic diversity in different stocks differed from each other; that is, a less genetic differentiation in the spawning and wintering stocks from the west coast of Korean Peninsula was revealed and their genetic diversities were higher than that of the spawning stock in the Bohai Sea and the China coast of the Yellow Sea. As detected, the genetic diversity in the successively cultivated stock was the lowest among these four stocks. Through genetic distance analysis between a random pair of individuals, a dendrogram of the above-mentioned four stocks was constructed by unweighted pair group method with arithmetic mean. The results based on cluster analysis well fitted with the geographical distribution of P. chinensis in the Bohai and Yellow Seas.