Xiao Li, Hu Ai-Qun, Wang Mei-Na, Cheng Zhuo, Chi Kuan-Bo, Long Chun-Lin, Liu Jin-Gang
College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen 518114, China.
Int J Mol Sci. 2025 Apr 7;26(7):3451. doi: 10.3390/ijms26073451.
Long-term clonality has profound consequences for genetic structure despite offering an alternative means of reproductive assurance under unfavorable conditions for sexual reproduction. Z. J. Liu & S. C. Chen (Orchidaceae), the only endangered species in China, exhibits a clear tendency towards asexual propagation, as evidenced by its small, fragmented wild populations. To develop effective conservation strategies for this species, it is essential to assess the extent of clonality and evaluate genetic diversity both within and among populations. In this study, we sampled 43 individuals from cultivated and wild populations of and analyzed their phylogenetic relationships, genetic structure, and diversity based on single-nucleotide polymorphisms (SNPs). Our results indicate that all the studied wild populations are predominantly sustained by vegetative growth, each forming a monoclonal patch with a single genotype. The overall genetic diversity within is low likely due to a combination of factors, including clonality, reduced effective population size, and environmental disturbances. These findings underscore the urgent need for the conservation management of this species. Conservation plans should prioritize ex situ conservation efforts, focusing on promoting assisted sexual reproduction to produce viable seeds and offspring that combine diverse genotypes from different populations. This study provides valuable insights in relation to effective conservation planning for endangered clonal species.
长期的克隆性对遗传结构具有深远影响,尽管在有性生殖的不利条件下它提供了一种生殖保障的替代方式。中国唯一的濒危物种独花兰(兰科)表现出明显的无性繁殖倾向,其野生种群规模小且碎片化就是证明。为制定该物种有效的保护策略,评估克隆性程度并评估种群内部和种群之间的遗传多样性至关重要。在本研究中,我们从独花兰的栽培种群和野生种群中采集了43个个体样本,并基于单核苷酸多态性(SNP)分析了它们的系统发育关系、遗传结构和多样性。我们的结果表明,所有研究的野生种群主要通过营养生长维持,每个种群都形成了一个具有单一基因型的单克隆斑块。独花兰的总体遗传多样性较低,这可能是多种因素共同作用的结果,包括克隆性、有效种群规模减小和环境干扰。这些发现凸显了对该物种进行保护管理的迫切需求。保护计划应优先进行迁地保护工作,重点是促进辅助有性生殖,以产生结合不同种群多样基因型的 viable 种子和后代。本研究为濒危克隆物种的有效保护规划提供了有价值的见解。