Chen Chaoqun, Chang He, Pang Xueyong, Liu Qinghua, Xue Lianfang, Yin Chunying
Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & Maoxian Mountain Ecosystem Research Station, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610213, P. R. China.
University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing, 100049, P. R. China.
BMC Plant Biol. 2025 Apr 28;25(1):552. doi: 10.1186/s12870-025-06581-z.
Cupressus chengiana is mainly distributed in the Hengduan Mountains area in China. It is one of the Class II endangered plants, ex situ conservation is often used to the affected C. chengiana population due to the construction of the power station. However, population fragmentation and inbreeding in the ex situ conservation have led to decline in genetic diversity. It is therefore important to clarify the differences in genetic diversity between native populations and ex situ population.
In this study, we used Genotyping-by-Sequencing to assess the genetic diversity of 30 C. chengiana trees from four populations in the Dadu River Basin, southwest China, including one ex situ conserved population (DK) and three native populations (BW, SA, RJ). The results showed that compared with the native populations, the DK population showed higher genetic diversity. Among the three native populations, SA population may experience inbreeding and has low genetic diversity. The population structure analysis further revealed that the DK population had higher gene flow and lower differentiation than other three populations. For ex situ populations, the primary determinant of genetic diversity is the genetic variation present in the seedlings sourced from natural populations.
These findings support the feasibility of ex situ conservation for C. chengiana conservation. This study provides a scientific foundation for the preservation, management, and restoration of C. chengiana, and would offer valuable insights for the conservation of other endangered plants.
岷江柏木主要分布于中国横断山脉地区。它是国家二级保护植物之一，由于电站建设，受影响的岷江柏木种群常采用迁地保护。然而，迁地保护中的种群碎片化和近亲繁殖导致了遗传多样性的下降。因此，明确原生种群和迁地种群之间的遗传多样性差异具有重要意义。
在本研究中，我们利用简化基因组测序技术评估了来自中国西南部大渡河流域四个种群的30株岷江柏木的遗传多样性，其中包括一个迁地保护种群（DK）和三个原生种群（BW、SA、RJ）。结果表明，与原生种群相比，DK种群具有更高的遗传多样性。在三个原生种群中，SA种群可能经历了近亲繁殖，遗传多样性较低。种群结构分析进一步表明，DK种群比其他三个种群具有更高的基因流和更低的分化程度。对于迁地种群而言，遗传多样性的主要决定因素是来自自然种群的幼苗中存在的遗传变异。
这些发现支持了岷江柏木迁地保护的可行性。本研究为岷江柏木的保护、管理和恢复提供了科学依据，并将为其他濒危植物的保护提供有价值的见解。
