Ministry of Education Key Laboratory of Xinjiang Phytomedicine Resource Utilization, College of Life Sciences, Shihezi University, Shihezi 832003, China.
Genes (Basel). 2023 Apr 29;14(5):1020. doi: 10.3390/genes14051020.
(M. Pop.) Cheng f. is a very important resource plant that integrates soil and water conservation, afforestation of barren mountains, and ornamental, medicinal, and scientific research functions and is also a critically endangered plant in China, remaining in only six small fragmented populations in the wild. These populations have been suffering from severe anthropomorphic disturbances, causing further losses in genetic diversity. However, its genetic diversity level and genetic differentiation degree among the fragmented populations are still unclear. Inthis study, DNA was extracted from fresh leaves from the remnant populations of , and the inter-simple-sequence repeat (ISSR) molecular marker system was used to assess its level of genetic diversity and differentiation. The result was that its genetic diversity is low at both species and population levels, with only 51.70% and 26.84% polymorphic loci, respectively. The Akeqi population had the highest genetic diversity, whereas the Ohsalur and Xiaoerbulak populations had the lowest. There was significant genetic differentiation among the populations, and the value of the genetic differentiation coefficient (Gst) was as high as 0.73, while the gene flow value was as low as 0.19 owing to spatial fragmentation and a serious genetic exchange barrier among the populations. It is suggested that a nature reserve and germplasm banks should be established as soon as possible for elimination of the anthropomorphic disturbances, and mutual introductions between the populations and introduced patches of the species, such as with habitat corridors or stepping stones, should be performed simultaneously to improve the genetic diversity of the isolated populations for the conservation of this plant.
珙桐（M. Pop.）是一种非常重要的资源植物，兼具水土保持、荒山造林、观赏、药用和科研功能，也是中国的极危植物，仅在野外残存的 6 个小的片段化种群中。这些种群一直受到严重的人为干扰，导致遗传多样性进一步丧失。然而，其遗传多样性水平和片段化种群间的遗传分化程度仍不清楚。本研究从残存种群的新鲜叶片中提取 DNA，利用简单序列重复区间（ISSR）分子标记系统评估其遗传多样性和分化程度。结果表明，其遗传多样性在种和种群水平都较低，多态性位点分别仅为 51.70%和 26.84%。阿克齐种群的遗传多样性最高，而奥萨尔湖和晓尔布拉克种群的遗传多样性最低。种群间存在显著的遗传分化，遗传分化系数（Gst）高达 0.73，而基因流值仅为 0.19，这是由于种群的空间片段化和严重的遗传交流障碍所致。建议尽快建立自然保护区和种质库，以消除人为干扰，并在种群之间以及引入物种的斑块之间进行相互引种，例如通过生境走廊或踏脚石，以提高隔离种群的遗传多样性，从而保护该植物。
