目的 利用SRAP分子标记技术对天麻种质资源进行遗传多样性研究，为天麻不同亲缘物种间的分类及其优良种质资源的筛选提供依据。方法 采集7个不同生态区域的天麻种质资源，包括红杆G. elata f. elata、乌杆G. elata f. glauca和绿杆G. elata f. viridis 3种变型和红乌杂交天麻，共24份样品。运用SRAP分子标记方法构建天麻种质的DNA指纹图谱，从分子水平检测其遗传多样性。结果 33对引物扩增出637条多态性条带，多态性百分率达73.16%。24份天麻种质样品间相似度分布于0.404 0～0.908 0，整个群体之间的相似程度差异较大。其中红天麻样品间的相似度在0.906 6～0.996 4，遗传差异较小；乌天麻、杂交天麻和绿天麻样品间的相似度分别在0.410 4～0.999 6、0.541 0～0.950 4和0.578 2，遗传差异较大。AMOVA分析结果显示，天麻变型内变异大于变型间变异，天麻各变型间有很大的遗传分化（FST=0.33，P<0.05）。另外，人工栽培对遗传分化有影响，但不显著。结论 SRAP分子标记方法得到的24份天麻样品多态性丰富，能有效地反映出天麻的遗传多样性。红杆天麻的遗传性状较为稳定，与其他变型间缺乏基因交流，遗传多样性匮乏；其他2个变型具有较高的遗传多样性。

Objective In order to correctly identify the different germplasm resources of Gastrodia elata and gain the excellent germplasm resources, SRAP molecular marker was used to analyze the genetic diversity of G. elata. Methods G. elata was collected from seven different areas, which included 24 smaples of G. elata f. elata, G. elata f. g1auca and G. elata f. viridis, the DNA figerprint of G. elata was constructed with SRAP molecular marker, and the genetic diversity was analyzed. Results Six huandred Thirty-seven belts were amplified by 33 primers pairs, and the polymorphic percentage was 73.16%. The range of genetic similarity coefficient was 0.404 0—0.908 0, the genetic similarity coefficient among G. elata f. elata was in the range of 0.906 6—0.996 4, and those of G. elata f. g1auca, G. elata f. viridis, and hybrid was in the range of 0.410 4—0.999 6, 0.541 0—0.950 4 and 0.578 2, respectively. They showed small genetic differences. The analysis of molecular variance showed higher percentages of genetic variation within population than those among populations in all species. Populations showed higher genetic structure (FST = 0.33, P < 0.05). In addition, artificial cultivation had influence to the genetic differentiation, but not significantly. So in terms of different cultivation conditions so far had no significant impact on the genetic differentiation of G. elata. Mantel's test has been used to detect the correlation between genetic distance and geographic distance of all sorts of germplasm resources, the result had no significant correlation, and due to the limited number of samples, the result is not representative. Conclusion SRAP molecular marker method can more effectively reflect the genetic polymorphisms of G. elata. Compared with other two phenotypes, G. elata f. elata is more conservative and has lower genetic diversity. The other two variants have higher genetic diversity.

国家科技支撑计划项目（2011BAI13B04-03）