长江、珠江、黑龙江三水系的鲢、镛、草鱼原种种群的生化遗传结构与变异

BIOCHEMICAL GENETIC STRUCTURES AND VARIATIONS IN NATURAL POPULATIONS OF SILVER CARP,BIG HEAD AND GRASS CARP IN CHANGJIANG RIVER,ZHUJIANG RIVER AND HEELONGJIANG RIVER

用LKB平板电泳仪聚丙烯酰胺凝胶电泳测定了长江、珠江及黑龙江的鲢、鳙及草鱼的原种8个种群16个酶位点的遗传变异。同种鱼不同水系种群之间存在着明显的生化遗传差异。长江、珠江、黑龙江鲢鱼种群的多态位点的比例分别是13.3％、26.7％、13.3％,平均杂合度分别是0.0493、0.0484、0.0511;长江、珠江鳙鱼种群的多态位点的比例都是31.3％,平均杂合度分别是0.1375,0.0977;长江、珠江、黑龙江草鱼种群的多态位点比例分别是30％,38％,23.1％,平均杂合度分别是0.1241,0.0961,0.0525。南方种群的多态位点比例有比北方的高的趋向。长江鲢—珠江鲢,长江鲢—黑龙江鲢,珠江鲢—黑龙江鲢的遗传相似度依次是0.9957,0.9955及0.9696;长江鳙—珠江鳙的遗传相似度是0.9955;长江草鱼—珠江草鱼,珠江草鱼—黑龙江草鱼,长江草鱼—黑龙江草鱼的遗传相似度依次是0.9679、0.9483及0.9324。长江种群与珠江种群这两个中央群体间的遗传差异较小,边缘群体黑龙江种群与中央群体长江、珠江种群间的遗传差异较大。黑龙江草鱼种群很小,其资源的保护工作应引起注意。

The genetic structures and variations of 16 enzyme loci in 8 populationsof silver carp,big head and grass carp from Chang Jiang River, Zhu Jiang River andHeilong Jiang River were analyzed by LKB horizontal acrylamide gel electrophoresis. Amarked biochemical genetic differences were found among different populations ofsame specics from different water systems. The mean proportion of polymorphic loci(P) was 13. 3%, 26. 7% and 13. 3%,the average heterozygosity per locus was 0 .0493, 0. 0484 and 0 .0511 for silver carppopulations from Chang Jiang River,Zhu Jiang River and Heilong Jiang River respe-ctively;For big head populations from Chang Jiang River and Zhu Jiang River,the Pwas both 31 .3%, but the H was 0.1375 and 0.0977 respectively;For grass carppopulations from Chang Jiang River,Zhu Jing River and Reilong Jiang River,the Pwas 30. 0%, 38. 0% and 21.3%, the H was 0.1241, 0.0961 and 0.0525 respectively.There was a trend that the mean prpportion of polymorphic loci in southern popula-tion was higher than that in northern population. The genetic similarity (S) of silver carps between Chang Jiang River and Zhu Ji-ang River,Chang Jiang River and Heilong Jiang River,Zhu Jiang River and HeilongJiang River was 0.9957, 0.9955 and 0.9696 successively;The S of big head popula-tions between Chang Jiang River and Zhu Jiang River was 0.9955; The S of grasscarp populations between Chang Jiang River and Zhu Jiang River,Zhu Jiang River andHeilong Jiang River, Chang Jiang Biver and Heilong Jiang River wax 0.9679, 0.9483and 0.9324 respectively. The genetic distance was smaller within the central popula-lions (Chang Jiang River and Zhu Jiang River),but was larger between the marginal populations(Heilong Jiang River) and the central population. The population size ofgrass carp in Heilong jiang River was very small, which should be given enoughaffention tco.