入侵植物加拿大一枝黄花和本地一枝黄花的遗传多样性比较

为了阐明加拿大一枝黄花成功入侵的机制,利用简单序列重复区间标记(ISSR)方法对加拿大一枝黄花和本地一枝黄花的遗传多样性进行比较研究。从100条引物中筛选出12条引物用于PCR扩增,利用POPGEN32软件对2种一枝黄花进行遗传多样性分析。结果表明,加拿大一枝黄花在物种水平上的多态位点百分率为95.19%,Nei’s基因多样性指数为0.308 5,Shannon’s信息指数为0.415 8;本地一枝黄花在物种水平上的多态位点百分率(89.80%)、Nei’s基因多样性指数(0.249 1)和Shannon’s信息指数(0.383 4)都比加拿大一枝黄花小。加拿大一枝黄花和本地一枝黄花居群间遗传分化系数分别为0.118 2和0.131 3,居群内变异分别为0.881 8和0.868 7,表明2个物种居群间的遗传分化不明显,遗传一致度高,且主要的遗传变异存在于居群内。入侵植物加拿大一枝黄花具有较高遗传多样性,且高于本地一枝黄花,这可能是加拿大一枝黄花成功入侵的原因之一。

Comparison in Genetic Diversity Between Invasive Species Solidago canadensis and Native Species S.decurrens

In order to explore mechanisms of the successful invasion of Solidago cannadensis,inter-simple sequence repeat(ISSR) markers were used to analyse genetic diversity of the invasive species S.canadensis and the native species S.decurrens for comparison.Out of 100 primers,12 were chosen for PCR amplification showing good diversity and clear bands.On such a basis,genetic diversities of the two plants were analyzed with the POPGEN32 software.For Solidago canadensis,the percentage of polymorphic loci at the species level,Nei′s gene diversity and Shannon′s information index was found to be 95.19%,0.308 5 and 0.415 8,respectively,whereas for the native species(S.decurrens) the three indices were found to be 89.80%,0.249 1 and 0.383 4,separately,all lower than the former,respectively.For S.canadensis,the coefficient of genetic differentiation among populations was 0.118 2 and the coefficient of genetic variation within the population was 0.881 8,while for S.demurrers,it was 0.131 3 and 0.868 7,respectively,suggesting insignificant genetic differentiation among the populations and highly consistent heredity of the two species.However,the main genetic variations exist within the populations,so the invasive species is higher than the native species S.decurrens in genetic diversity,which might be responsible for the successful invasion of S.canadensis.