三个群体罗氏沼虾线粒体COI基因的遗传多样性分析

运用PCR方法,扩增罗氏沼虾缅甸原种F1代、广西选育群体和江苏养殖群体的线粒体DNA上的细胞色素氧化酶(Cytochrome oxidase subunit I,COI)基因,在此基础上选用10种限制性内切酶对扩增产物进行限制性片段长度多态(RFLP)分析。三个群体共发现2个多态位点,11种酶切图谱,3种基因型。三群体的多态座位比例、平均杂合度和基因型多样性指数分别为:缅甸原种F122.2%、0.0556、0.0472,广西选育群体22.2%、0.0400、0.0398,江苏养殖群体11.1%、0.0106和0.0083,群体间遗传差异未见显著。根据群体间遗传距离构建UPGMA聚类关系图,显示广西选育群体和江苏养殖群体间的遗传关系较近,而与原种F1群体的遗传关系较远。

The genetic diversity of COI gene in mitochondrial DNA of three populations of Macrobrachium rosenbergii

With the method of PCR,the Cytochrome oxidase subunit I(COI) gene is amplified to investigate the genetic diversity and genentic difference of three populations of Macrobrachium rosenbergii,including F_1 of wild population from Burma,breeding population from Guangxi local farm and cultured population from Jiangsu Province,10 endonucleases(ApaI,Acc65I,Fnu4hI,BsrfI,BsrI,KpnI,HphI,FokI,BanI,TaqI) are applied to digest the PCR products of COI gene from 30 samples,10 samples per population.The digested DNA fragments are shown with 3% agrose gel.The electrophoresis patterns indicate that in COI gene,these three populations have 2 polymorphic loci,11 kinds of endonucelease patterns and 3 kinds of genotypes.The proportion of polymorphic loci,mean heterozygosity,genotype diversity respectively are:22.2%,0.055 6 and 0.047 2 in F_1 of wild population;22.2%,(0.040 0) and 0.039 8 in breeding population;11.1%,0.010 6 and 0.008 3 in cultured population,which shows that F_1 of wild population and breeding population have higher genetic diversity than cultured population,while genetic difference among these three populations is not significant by t-test(P>0.10).The UPGMA clustering phenogram indicates that the breeding population from Guangxi has a closer relationship with cultured population from Jiangsu than that with F_1 of wild population from Burma,and to some degree reveals the effectiveness and limitation of artificial breeding in Macrobrachium rosenbergii.