川滇地区麻疯树遗传多样性及亲缘关系的cpSSR研究

目的:研究川滇地区麻疯树遗传多样性,探讨居群间亲缘关系,为合理利用麻疯树种质资源及良种选育奠定理论基础。方法:作者运用12对叶绿体微卫星(cpSSR)标记引物对10个麻疯树野生居群进行分析,将扩增出的条带作为原始矩阵,用POPGENE version 1.32软件分析遗传多样性参数,并采用NTSYSpc version 2.10软件进行UPGMA聚类分析,构建系统树状图。结果:共检测到多态性位点22个,多态性位点百分率(P)平均为76.28%。其中,云南双柏(YNSB)居群多态性位点百分率最高,达95.45%;而云南泸水(YNLS)居群多态性位点百分率最低,仅45.45%。Nei’s基因多样性指数He 0.402 0,Shannon信息多样性指数I 0.576 7,有效等位基因数Ae 1.713 6,总基因多样性(HT)0.443 3,基因分化系数Gst 0.080 2,基因流(Nm)3.058 5;居群内基因多样性HS 0.405 1,居群间基因多样性(Dst)0.035 7,表明麻疯树居群内的基因多样性在总居群基因多样性中所占比例较大,麻疯树居群间几乎没有分化;ANOVA分析结果表明,91.02%的变异来源于居群内,8.98%变异来源于居群间,即10个供试麻疯树居群遗传变异主要发生在居群内,居群内的遗传变异大于居群间的遗传变异,这与Nei’s基因分化系数分析结果一致;麻疯树各居群遗传多样性由低到高依次为:云南泸水(YNLS)居群<云南西双版纳(XSBN)居群<四川花棚子(SCHPZ)居群<四川会东(SCHD)居群<四川金河(SCJH)居群<云南普洱(YNPR)居群<四川雷波(SCLB)居群<云南双柏(YNSB)居群<云南法依(YNFY)居群<四川会理(SCHL)居群;10个麻疯树居群的遗传一致度为0.812 7～0.979 8;遗传距离为0.020 4～0.207 3,表明这10个居群间的相似程度较高,遗传距离较小,亲缘关系较近;UPGMA聚类分析显示:10个麻疯树居群可分为两大类,即SCJH居群和SCHPZ居群聚为一类;SCHL居群、SCHD居群、SCLB居群、YNSB居群、YNFY居群、YNPR居群、XSBN居群和YNLS居群聚为另一类。结论:川滇地区麻疯树具有丰富的遗传多样性,但各居群间亲缘关系较近。

Genetic diversity and genetic relationship of Jatropha curcas L. in Sichuan and Yunnan evaluated by cpSSR markers

Objective: The genetic diversity and genetic relationship of Jatropha curcas resources in Sichuan and Yunnan were studied in order to provide a theoretical basis for breeding fine varieties and protecting germplasm resources. Method: Ten J. curcas populations were studied by 12 cpSSR primers in this paper. On the base of amplified bands, genetic diversity parameters were analyzed by POPGENE version 1.32. Furthermore, UPGMA tree of 10 J. curcas populations established from pairwise population distance by NTSYSpc version 2.10. Result: Twenty-two polymorphic bands were detected, and the percentage of polymorphic loci (P) was 76.28%. Among of the 10 J. curcas populations, the average percentage of polymorphic loci of YNSB was higher than that of the other populations, and it reached 95.45%; On the other hand, that of YNLS was the lowest in all populations, and it was 45.45%. Nei's gene diversity index(H_e), Shannon information index(I), Effective Num of alleles(A_e) were respectively 0.402 0, 0.576 7,1.713 6. The total gene diversity (H_T), the gene differentiation coefficient (G_st), the gene flow (N_m) and the gene diversity within populations ( H_S) were 0.443 3, 0.080 2, 3.058 5, 0.405 1, 0.035 7, respectively. The highest gene diversity ratio was showed within populations and the lowest among populations. The results by AMOVA analysis showed that 91.02% of genetic variation existed within populations while 8.98% of genetic variation existed among populations. On the base of the results, the conclusion was extracted that variation existed mainly within populations, and the variation within populations was bigger than that among populations. The result was consistent with that of the gene differentiation coefficient. The order of the genetic diversity was YNLS population