Genetic differences between Cultured and Wild penaeid shrimp (Penaeus chinemis) populations analysed by RAPD-PCR

摘要

Of the 20 arbitrarily selected primers, seven decamer primers were used on the basis of the number of the genetic diversity and similarity generated in penaeid shrimp (Penaeus chinensis) from Kunsan in Korea. Seven decamer primers generated a totalof 317 fragment in cultured penaeid shrimp and 385 in wild penaeid shrimp, of which 102 polymorphic fragments (32.2 percent) in cultured and 148 (38.4 percent) in wild, respectively. A total of 264 identical fragments (an average of 37.7 per primer) wereobserved in wild penaeid shrimp, whereas 187 common fragments (an average of 26.7 per primer) in cultured shrimp. The total number of specific fragments in cultured and wild populations were 28 and 25, respectively. Seven random primers yielded amplified fragments which were consistently polymorphic and specific between two populations. The bandsharing value between No. 10 and No. 11 in cultured population showed the highest level (0.917) within cultured penaeid shrimp population, whereas that value between No. 1 and No. 14 in wild population showed the lowest level (0.481). The single linkage dendrogram resulted from reliable four primers (OPA-07, OPA-12, OPB-04 and OPB-19), indicating five genetic groupings composed of group 1 (Cultured No. 1), group 2 (Cultured No. 6, 2 and 9), group 3 (Cultured No. 11, 10, 3, 8, 7, 4 and 5), group 4 (Wild No. 12, 14, 13, 20, 19, 18, 16, 17, 15 and 22) and group 5 (Wild No. 21). The genetic distances between two populations ranged from 0.118 to 0.126. Especially,the genetic distance between Cultured No. 1 and Wild No. 21 among individuals in two populations vras highest (0.126). This result suggested that Cultured No. 1 and Wild No. 21 are distinct from any other individuals in two cultured and wild populations.The oligonucleotide primer OPA-07 generated identical DNA fragments whose sizes of approximately 230 bp and 250 bp, respectively, between cultured and wild penaeid shrimp population. As calculated by bandsharing analysis, the average level of genetic difference (mean +- SD) was approximately 0.282 +- 0.107 in cultured population and 0.213 +- 0.063 in wild population, respectively. As compared separately, the average level of genetic difference in cultured population was higher than that in wild population. However, the average level of genetic difference was also approximately 0.327 +- 0.072 between cultured and wild population. Ultimately, PCR analysis based on the RAPD data showed that the cultured population of penaeid shrimp was more or less separated from the wild population. Genetic identification of penaeid shrimp populations are necessary steps for broodstock selection and selective invertebrate breeding programs.