青海省冬虫夏草的遗传变异及亲缘关系的形态性状和ISSR分析

Genetic variation and aiffinity of Cordyceps sinensis in Qinghai Province based on analysis of morphologic characters and inter-simple sequence repeat markers

目的探讨青海省不同地区冬虫夏草的鉴定方法,并评价其遗传变异、亲缘关系及地域分布。方法利用形态性状和ISSR标记分析青海省11个县的冬虫夏草样品。结果青海省不同地区的冬虫夏草无论是形态性状还是ISSR多态性都存在很大的遗传变异。根据形态性状数据,青海省的冬虫夏草大致分成3个组,即分别产于环青海湖地区、青海中东部和南部,但仅基于形态性状来鉴定特定的冬虫夏草十分费力且不可靠。根据ISSR指纹图谱能够鉴定不同产地的冬虫夏草,而且ISSR分析表明青海省的冬虫夏草可分成产于环青海湖地区和其他地区两大类,其他地区一大类又可分成青海省南部、中部和东部产区3个平行分支。结论青海省的冬虫夏草在分布上表现出明显的地域性。ISSR分子标记对于冬虫夏草的鉴定和亲缘关系检测是非常有效的手段,与形态性状分布相结合效果更佳。

Objective To identify Cordyceps sinensis from different habitats in Qinghai Province of China and estimate their genetic variation, affinity, and regional distribution. Methods Morphological characters and inter-simple sequence repeat （ISSR） markers were analyzed among the C. sinensis samples from 11 Counties in Qinghai Province. Results Significant genetic variations were detected in both morphological characters and ISSR polymorphisms among these C. sinensis samples. Data from morphological analysis showed that these C. sinensis samples could he approximately divided into three groups, which distributed around the Qinghai Lake, middle east, and south areas in Qinghai Province, respectively. However it was arduous and ambiguous to identify the specific samples only by morphological characters. Based on the analysis of ISSR markers, C. sinensis of Qinghai Province could be classified into two major groups. One included the samples from the areas around the Qinghai Lake and another from the other two areas, one of which could be further divided into three subgroups, well correlated with the different habitats of south, center, and east areas in Qinghai Province, respectively. Conclusion C. sinensis with genetic variation and affinity in Qinghai Province distributes widely according to their living environment. ISSR analysis is an effective tool in identifying C. sinensis samples and determining their genetic affinity particularly when combined with the analysis of morphological characters.