4种红豆杉属植物遗传多样性和遗传关系的RAPD分析

RAPD analysis of genetic diversity and genetic relationship of four species in Taxus Linn

采用RAPD标记研究了分属于4种红豆杉属(Taxus Linn.)植物的68个单株的遗传多样性,并采用UPGMA方法分析68个单株的遗传关系。结果表明:12条RAPD引物共扩增出109条带,其中多态性条带108条,多态性条带百分率为99.1%;平均每条引物扩增出9.1条带。南方红豆杉〔T.wallichiana var.mairei(Lemée et Lévl)L.K.Fu et Nan Li.〕种内的多态性条带百分率和观察等位基因数均最高;欧洲红豆杉(T.baccata Linn.)种内的有效等位基因数、Nei’s基因多样度和Shannon’s信息指数均最高;须弥红豆杉(T.wallichiana Zucc.)种内的各项遗传多样性指数均最低。供试4种植物的种内遗传多样度、种间遗传多样度、基因流和种间遗传分化系数分别为0.174 5、0.358 6、0.401 7和0.554 5,表明55.45%的遗传变异发生在种间。南方红豆杉和须弥红豆杉遗传距离最近;曼地亚红豆杉(Taxus×media Rehd.)和须弥红豆杉的遗传距离最远。通过聚类分析可将68个单株分为3组,欧洲红豆杉的18个单株和曼地亚红豆杉的18个单株分别各自聚为1组;须弥红豆杉的16个单株和南方红豆杉的16个单株聚为1组,其中须弥红豆杉的16个单株和南方红豆杉的16个单株又各自聚为1个亚组,且南方红豆杉的雌、雄单株也分别聚在同一分支上,表明须弥红豆杉和南方红豆杉遗传关系较近,而欧洲红豆杉与其他3种植物的遗传关系较远。

By means of RAPD marker, genetic diversity of sixty-eight individuals belonging to four species in Taxus Linn. was studies, and their genetic relationship also was analyzed by UPGMA cluster method. The results show that 109 bands are amplified by 12 RAPD primers, in which, 108 bands are polymorphie bands with 99. 1% of percentage of polymorphic band, and average number of bands amplified by each primer is 9.08 bands. Percentage of polymorphic band and observed number of alleles of intraspeeies of T. waUichiana var. mairei （Lem6e et L6vl ） L. K. Fu et Nan Li. are the highest, effective number of alleles, Nei＇ s genetic diversity and Shannon＇ s information index of intraspeeies of T. baccata Linn. are the highest; while all genetic diversity indexes of T. wallichiana Zucc. are the lowest. Intraspecies genetic diversity, interspecies genetic diversity, gene flow and interspecies gene differentiation index of four species tested are 0. 174 5, 0. 358 6, 0. 401 7 and 0. 554 5, respectively, meaning that 55.45% of genetic variation exists among species. Genetic distance between T. waUichiana var. mairei and T. wallichiana is the nearest, while that between T. x media Rehd. and T. wallichiana is the farthest. Sixty-eight individuals can be divided into three groups by cluster analysis, eighteenindividuals of T. baccata and eighteen individuals of T. x media can be independently clustered into one group, respectively. And sixteen individuals of T. wallichiana and sixteen individuals of T. wallichiana var. mairei are gathered into one group, each in which is also gathered independently to form into one sub-group, respectively, while female and male individuals of T. wallichiana var. mairei are gathered into the same branch, respectively. It means that relationship between T. waUichiana and T. wallichiana var. mairei is more close while T. baccata has a further relationship with other three species.