孑遗植物中华桫椤2个群体遗传多样性的ISSR分析

ISSR Analysis of the Genetic Diversity within Two Populations of Relict Plant,Alsophila costularis (Cyatheaceae)

为阐明小尺度范围内濒危物种孑遗植物中华桫椤种群的遗传多样性,保护和恢复种质资源,本文采用ISSR分子标记技术对云南屏边大围山的大围山红旗水库和大围山山谷2个中华桫椤种群的遗传多样性进行分析。结果表明用从100个随机引物中筛选出的20个能高产稳定扩增的ISSR引物对2个群体共57个样品进行扩增,共获得132个可分析位点,其中大围山红旗水库的多态性位点83个,占62.87%,而大围山山谷的多态性位点97个,多态位点百分率(P)为73.48%,两者Nei's基因多样性分别为0.2614和0.2832,Shannon's信息指数分别为0.3762和0.4135,两个种群的遗传分化系数Gst为0.0701,分析结果表明中华桫椤种群内的遗传多样性较高,但两种群间的遗传分化不明显。本研究结果将对中华桫椤自然群体的保育和管理具有重要意义。

In order to illuminate the genetic diversity of endangered species relict plant Alsophila costularis populations within a small range as well as keeping and resuming germplasm resource,in this paper,we analyzed the genetic diversity of two Alsophila costularis populations,which was Daweishan Hongqi Shuiku and Daweishan Shangu respectively,located Daweishan in Pinbian city Yunnan Province by using ISSR molecular marker technique.The results showed that among 100 radom primers,20 coule yield highly reproducible and stable DNA fragments,could be screened to 57 samples of two populations,and we totally obtained 132 discernible sites,of which polymorphism loci of Daweishan Hongqi Shuiku was 83,accounting for 62.87%,while that of Daweishan Shangu was 97 and 73.48% respectively.Both of them,the Nei＇s gene diversity was 0.261 4 and 0.283 2 respectively,and the Shannon＇s information index carried on 0.376 2 and 0.413 5 respectively.Further,the coefficient gene differentiation （Gst） between the two populations is 0.070 1.These analysis results indicated that there was high level of genetic diversity within populations,but low level of genetic differentiation between the two populations.On the basis of these results,strategies were suggested for the conservation and management of the species.