ABSTRACT
Objective: The genetic diversity of wild Bletilla striata from different sources was analyzed in order to provide the reference value for breeding, protection and development of B. striata germplasm in the future. Methods: Genetic diversity of 50 wild B. striata samples was identified by SRAP molecular marker technique, and the genetic relationship was analyzed by UPGMA method. Results: A total of 117 bands were amplified from 50 samples by using 15 SRAP primer combinations, with an average of 7.8 bands per primer. Among them, 106 bands were polymorphic, with a polymorphism rate of 90.60%. The clustering results showed that the genetic similarity coefficient of 50 B. striata samples was 0.59-0.87, which could be divided into six categories based on the genetic coefficient of 0.66. The genetic distance of two pieces of B.striata from No.2 Lijiang, Yunnan and No.2 Jingshan County, Hubei was not directly related to geographical distance. Conclusion: There are abundant genetic diversity among wild B. striata resources, and there is no direct relationship between geographical distance and genetic distance. SRAP technology can provide theoretical basis for the protection of B. striata resources and variety breeding, which provides reference for the subsequent development and utilization of B. striata.
ABSTRACT
Bletilla striata has been used as traditional Chinese medicine for several centuries. In recent years, the quality and quantity of wild B. striata plants have declined sharply due to habitat deterioration and human over-exploitation. Therefore, it is of great urgency to evaluate and protect B. striata wild plant resource. In this study, sequence-related amplified polymorphism (SRAP) markers were applied to assess the level and pattern of genetic diversity in twelve populations of B. striata. The results showed a high level of genetic diversity (PPB = 90.48%, H = 0.349 4, I = 0.509 6) and moderate genetic differentiation among populations (Gst = 0.260 9). Based on the unweighted pair-group method with arithmetic average (UPGMA), twelve populations gathered in three clusters. The cluster 1 included four populations. There are Nanjing, Zhenjiang, Xuancheng and Hangzhou. The seven populations which come from Hubei Province, Hunan Province, Jiangxi Province and Guizhou Province belonged to the cluster 2. The cluster 3 only contained Wenshan population. Moreover, Mantel test revealed significant positive correlation between genetic distances and geographic distances (r = 0.632 9; P B. striata.