菊黄东方鲀野生和人工选育群体遗传变异的SSR和ISSR分析

利用SSR和ISSR两种分子标记技术,对菊黄东方鲀的人工选育群体(SH)和野生群体(YS)的遗传变异和遗传结构进行了联合分析。SSR分析的结果显示,14个微卫星位点总共获得了146个等位基因,选育和野生群体的平均期望杂合度(He)分别为0.730 0和0.832 3,平均多态信息含量(PIC)分别为0.705 1和0.813 6;ISSR结果显示,选育和野生群体的平均Nei’s基因多样性指数(H)分别为0.267 2和0.282 3,平均Shannon信息指数(I)为0.407 2和0.425 6,表明菊黄东方鲀选育群体的遗传变异程度低于野生群体。此外,两种分子标记遗传分化的结果显示,两个群体的遗传分化指数分别为0.061 9(SSR)和0.061 5(ISSR),表明两个群体已经产生了中等程度的遗传分化。综上,本单位菊黄东方鲀的人工选育群体仍然具有相对较丰富的遗传变异以供进一步的遗传改良。

Genetic variation analysis between wild and selected populations of Takifugu flavidus using SSR and ISSR markers

Simple Sequence Repeat(SSR)and inter-simple sequence repeat (ISSR) markers were applied to measure the genetic variation and genetic structure of the selected stock (SH) and wild population (YS) of Takifugu flavidus. Results of SSR showed that a total of 146 alleles were detected among 60 individuals with 14 polymorphic microsatellite loci, and the mean of expected heterozygosity (He) and polymorphism information content (PIC) of two populations ranged from 0.730 0 to 0.832 3 and from 0.705 1 to 0.813 6, respectively. The analysis of ISSR showed that the average Nei''s gene diversity index (H) of selected stock and wild population were 0.267 2 and 0.282 3, respectively, while the average Shannon information index (I) of two populations were 0.407 2 and 0.425 6, respectively. These results showed that the genetic variation of wild population was higher than that of the selected population of Takifugu flavidus. Additionally, genetic differentiation coefficient (F_ST) value between the two populations of Takifugu flavidus were 0.061 9 (SSR) and 0.061 5 (ISSR), which indicated that two populations generated moderate genetic differentiation. These results above indicated that the selective breeding stock of Takifugu flavidus still possessed abundant genetic variation at population level, and had great potential for artificial selection and breeding.