【摘要】 通过测定罗氏沼虾(Macrobrachium rosenbergii)人工养殖群体(A)(浙江湖州)、缅甸引进群体F2代(B)和"南太湖1号"(C)3个群体线粒体控制区(D-loop)基因序列片段(约1200bp),探讨罗氏沼虾群体遗传结构。结果发现,在用于分析的1121 bp基因序列中有86个变异位点,共计14个单倍型。其中,群体A、C的遗传多样性均较低,其π值分别为0.022和0.025,相比之下,群体B的遗传多样性则明显要高于上述两个群体(π=0.032)。AMOVA分析表明,群体间的遗传变异占总遗传变异的6.32%,而93.68%的遗传变异源于群体内。对三群体的遗传学参数计算结果表明,群体A和B间遗传分化指数(Fst)为0.105,已达到中等分化水平;群体C与A间的遗传距离(D=0.025)最小,提示它们的亲缘关系最近。本研究结果认为,D-loop基因可以作为检测罗氏沼虾群体遗传差异的分子标记,"南太湖1号"群体遗传多样性比人工养殖群体有所提高,但仍偏向养殖群体,未表现出最高的杂种优势。更多还原

【Abstract】 Using nucleotide sequences from control region(D-loop) gene of mitochondrial,this paper investigated the genetic structure of giant freshwater prawn Macrobrachium rosenbergii among three different populations,which are cultured population from Huzhou,Zhejiang province(A),the second offspring of induced population from Burma(B),and "South Tailake No.1"(C).The results from sequencing an approximately 1200 bp fragment of this gene region revealed 14 haplotypes based on polymorphisms at 86 nucleotide sites.Among the three populations,both populations A and B exhibit lower level of variability(π=0.022,0.025),and population B exhibits the highest level of variability(π=0.032).Analysis of molecular variance indicated that large mtDNA differentiation occurred within populations(93.68%),and 6.32% occurred among populations.The calculation of genetic parameters suggested that genetic differential index between population A and B was 0.105,and the degree of genetic differentiation was moderate.The genetic distance between population A and C was the lowest,and the two populations were closest genetically.In conclusion,D-loop gene could be a genetic marker for examining genetic difference of M.rosenbergii."South Tailake No.1" had larger genetic diversity.It hadn’t developed the highest heterosis as it was too close to cultured population.更多还原