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鲟形目(Acipenseriformes)鱼类是一类多倍体起源的鱼类,种间易于杂交,且由于存在大量微型染色体,其染色体数目和倍性也难于确定。到目前为止包括达氏鳇(Huso dauricus)在内的一些鲟鱼物种基因组大小和染色体倍性仍旧存在争议。本实验采用微卫星遗传标记技术,通过观察9个微卫星位点的等位基因数目,发现达氏鳇在大部分位点中显示的倍性大于二倍性,同时利用多倍体分析软件POLYSAT推断了26尾达氏鳇的个体倍性。结果表明,26尾达氏鳇中有20尾显示为六倍体,占总数的76.92%;4尾显示为八倍体,占总数的15.38%;2尾显示为四倍体,占总数的7.79%。因此,我们认为达氏鳇应该为八倍体物种,结果中出现的四倍体和六倍体个体,是由于这些个体在我们选取的微卫星位点中存在部分纯合等位基因,导致了多数个体显示为六倍体。这一结论与近年来支持达氏鳇为进化性八倍体物种的研究结果一致。
Acipenseriformes, a kind of polyploid fish, is easy to cross between species, and its chromosome number and ploidy are difficult to determine because of the presence of a large number of miniature chromosomes. The genome size and chromosome ploidy of some sturgeon species, including Huso dauricus, remain controversial until now. In this experiment, microsatellite markers were used to observe the number of alleles in nine microsatellite loci. It was found that the ploidy of Daphniphyllum was greater than diploid in most loci. Polyploid analysis software POLYSAT Extrapolation of the individual ploidy of 26 Lepidoptera. The results showed that twenty-six of the 26 individuals showed hexaploid, accounting for 76.92% of the total; four showed eight-fold, accounting for 15.38%; two showed tetraploid, accounting for 7.79 %. Therefore, we consider that T. solani should be an octoploid and that tetraploid and hexaploid individuals appear as a result of the presence of some homozygous alleles in the microsatellite loci we selected Most individuals show hexaploid. This conclusion is in line with the findings of recent studies supporting evolutionary Octopus spp.