2种双壳贝类染色体的观察研究

Observation on the Chromosomes in 2 Species of Bivalve

[目的]为贝类的细胞遗传学研究提供基础资料。[方法]以等边浅蛤和江户布目蛤的鳃组织为研究材料,用植物血球凝集素和秋水仙素对2种双壳贝类的腮组织进行处理后,采用滴片-空气干燥法制片并观察其染色体数目。[结果]通过观察2种贝类的中期分裂相,发现等边浅蛤的染色体众数为36的分裂相细胞,占全部计数细胞的55.0%,说明其染色体数目(2n)为36。而江户布目蛤的染色体众数为30的分裂相细胞,占全部计数细胞的58.8%,说明江户布目蛤的染色体数目(2n)为30。[结论]从细胞水平上看,日本镜蛤(2n=30)和江户布目蛤有较亲密的亲缘关系,而青蛤(2n=36)和等边浅蛤也有较亲密的亲缘关系。

[Objective] The aim of the research was to provide the basic data for the cytogenetic study of shellfish.[Method] With gill tissues of Gomphina aequilatera and Protothaca jedoensis as research materials,after the gill tissues of 2 species of bivalve were treated with phytohemagglutinin and colchicine,specimens were prepared by using dripping tablets and air drying method to observe the chromosome number.[Result] Through observing the metaphases of 2 species of shellfish,it was found that the divding cells in G.aequilatera with the chromosome mode of 36 occupied 55.0% in all counted cells,which indicated that its chromosome number（2n） was 36.The dividing cells in P.jedoensis with the chromosome mode of 30 occupied 58.8%all counted cells,which indicated that its chromosome number（2n） was 30.[Conclusion] At the cellular level,Dosinia japonica（2n=30） had closer genetic relationship with P.jedoensis,while Cyclina sinensis（2n=36）had closer genetic relationship with G.aequilatera.