黑龙江多布库尔河和新疆额尔齐斯河江鳕的形态特征及生化遗传分析

Morphological comparison and isozyme analysis of Lota lota populations in Duobuku’er River and Eerqisi River

对采自黑龙江多布库尔河和新疆额尔齐斯河江鳕(Lotalota)的两个群体样本进行了形态学研究和生化遗传分析。在形态学水平上,38项可比特征中有26项(68.42%)差异达到极显著水平(P<0.01)。根据Mayr差异系数C.D≥1.28的亚种划分标准,尾柄高相对体长的百分比和幽门盲囊数目两项特征支持两个群体的差异达到亚种水平。利用同工酶技术分析两个群体的遗传结构,结果表明,所检测的8个基因位点中,额尔齐斯河江鳕全部为单态,而多布库尔河江鳕在G3PDH?位点呈多态,两个群体在G3PDH?位点的基因频率达到近似基因置换的水平,群体间遗传距离为0.08286。结合其他研究结果,黑龙江多布库尔河和新疆额尔齐斯河的江鳕应为不同亚种。

Duobuku＇ er River is a branch of Amur River. Two populations of burbot Lota Iota in Duobuku＇ er River and Eerqisi River were analyzed using morphological measurement and isozyme assay. Thirty eight morphological characters were measured, of which, 26 （68.42%） showed significant difference （P〈 0.01） between the two populations. The difference of two characters, ratio of caudal peduncle depth to standard body length and pyloric caeca number, reached subspecies level by the criteria of C.D ≥ 1.28. Six different isoenzymes were assayed using horizontal starch gel electrophoresis. Results showed that these 6 isoenzymes are encoded by 8 loci. All but G3PDH^＊ locus in population of Duobuku＇ er River are monomorphic. Alle frequency at G3PDH locus of the two populations are next to alle replacement. Nei＇ s genetic distance was estimated as 0.0826, indicating that the two populations are different subspecies. Based on these present results and previous data of other authors, burbot in Duobuku＇ er River could be regarded as a new subspecies. [Journal of Fishery Sciences of China, 2008, 15 （3）： 386-391]