Evaluation of genetic diversity and population structure of Bletilla striata based on SRAP markers / 药学学报

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.

Evaluation of genetic diversity and population structure of Bletilla striata based on SRAP markers / 药学学报

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 (G(st) = 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 < 0.000 1). According to the results, we proposed a series of conservation consideration for B. striata.

Applylication of new type combined fragments: nrDNA ITS+ nad 1-intron 2 for identification of Dendrobium species of Fengdous / 药学学报

In this study, 17 kinds of Dendrobium species of Fengdous including 39 individuals were collected from 4 provinces. Mitochondrial gene sequences co I, nad 5, nad 1-intron 2 and chloroplast gene sequences rbcL, matK amd psbA-trnH were amplified from these materials, as well as nrDNA ITS. Furthermore, suitable sequences for identification of Dendrobium species of Fengdous were screened by K-2-P and P-distance. The results showed that during the mentioned 7 sequences, nrDNA ITS, nad 1-intron 2 and psbA-trnH which had a high degree of variability could be used to identify Dendrobium species of Fengdous. However, single fragment could not be used to distinguish D. moniliforme and D. huoshanense. Moreover, compared to other combined fragments, new type combined fragments nrDNA ITS+nad 1-intron 2 was more effective in identifying the original plants of Dendrobium species and could be used to identify D. huoshanense and D. moniliforme. Besides, according to the UPGMA tree constructed with nrDNA ITS+nad 1-intron 2, 3 inspected Dendrobium plants were identified as D. huoshanense, D. moniliforme and D. officinale, respectively. This study identified Dendrobium species of Fengdous by combined fragments nrDNA ITS+nad 1-intron 2 for the first time, which provided a more effective basis for identification of Dendrobium species. And this study will be helpful for regulating the market of Fengdous.