濒危植物百山祖冷杉和资源冷杉的物种划分及其遗传资源的保护  

Species delimitation and genetic conservation of the endangered firs Abies beshanzuensis and A.ziyuanensis

作　　者：杨玲 梁思琪 潘佳明 韦金鑫 丁涛[4] 蒋日红 邵毅贞 张宪春[1,2] 刘勇波 向巧萍[1,2] YANG Ling;LIANG Si-Qi;PAN Jia-Ming;WEI Jin-Xin;DING Tao;JIANG Ri-Hong;SHAO Yi-Zhen;ZHANG Xian-Chun;LIU Yong-Bo;XIANG Qiao-Ping(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China;China National Botanical Garden,Beijing 100093,China;College of Life Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Guangxi Institute of Botany,Chinese Academy of Sciences,Guilin,Guangxi 541006,China;Guangxi Forestry Research Institute,Nanning 530002,China;College of Life Sciences,Henan Agricultural University,Zhengzhou 450002,China;State Environment Protection Key Laboratory of Regional Ecological Process and Functional Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]中国科学院植物研究所,系统与进化植物学国家重点实验室,北京100093 [2]国家植物园,北京100093 [3]中国科学院大学生命科学学院,北京100049 [4]广西壮族自治区中国科学院广西植物研究所,广西桂林541006 [5]广西壮族自治区林业科学研究院,南宁530002 [6]河南农业大学生命科学学院,郑州450002 [7]中国环境科学研究院,国家环境保护区域生态过程与功能评估重点实验室,北京100012

出　　处：《植物生态学报》2023年第12期1629-1645,共17页Chinese Journal of Plant Ecology

基　　金：生态环境部生物多样性调查与评估项目(2019HJ2096001006)。

摘　　要：物种是生物学中最基本的分类单元,对于珍稀濒危物种而言,物种的正确界定对于制定保护措施至关重要。分布于中国亚热带地区的百山祖冷杉(Abies beshanzuensis)、资源冷杉(A. ziyuanensis)和大院冷杉(A. dayuanensis)种群极小,且分类上长期存在争议。现行分类依据形态和地理分布将大院冷杉归并到资源冷杉,又将资源冷杉处理为百山祖冷杉的变种,但分子证据不足。该研究对百山祖冷杉、资源冷杉和大院冷杉分布区内8个种群的23株个体进行靶向捕获测序,获得了60个单拷贝核基因中的805个单核苷酸多态性位点。种群遗传结构和历史动态分析表明,这些个体可分为两个谱系,分别对应于百山祖冷杉和资源冷杉,其中资源冷杉在2.35Ma前与百山祖冷杉和大院冷杉的共同祖先分化,而大院冷杉与百山祖冷杉亲缘关系更近,形成一个谱系。百山祖冷杉、资源冷杉和大院冷杉的遗传多样性水平整体较低,种群间存在较为明显的遗传分化(遗传分化指数0.083–0.208)。由于未检测到分化后的谱系间遗传交流,推测分布区的碎片化是谱系间遗传交流受阻进而产生分化的主要原因。生态位比较分析结果显示百山祖冷杉、资源冷杉和大院冷杉这群濒危冷杉分布区的年平均气温和最冷季平均气温显著高于东亚分布的非濒危冷杉物种,因此,该研究认为全球气候变暖是导致其濒危的关键因素。综合以上研究结果,该研究对百山祖冷杉、资源冷杉和大院冷杉这群植物进行新的分类处理,将大院冷杉处理为百山祖冷杉的异名,确认资源冷杉种的地位。在对其濒危机制深入理解的基础上,建议在西南的横断山和秦巴山地区尝试迁地栽培实验,同时就地人工辅助育种。Aims“Species”is the basic taxonomical unit in biology.The accuracy of endangered species delimitation largely determines the efficiency and conservation strategies.Abies beshanzuensis,A.ziyuanensis and A.dayuanensis,a group of endangered firs endemic to the subtropical region of China,have extremely small populations and controversial taxonomy.According to morphological differences and geographical distribution,A.dayuanensis has been considered as the synonym of A.ziyuanensis,whereas A.ziyuanensis is currently treated as a variety of A.beshanzuensis.However,no genetic evidence has been provided to test this classification hypothesis.Methods We performed target enrichment sequencing on 23 individuals from eight extant populations and obtained 805 single nucleotide polymorphic sites from 60 single-copy nuclear genes for population genetic analyses.Important findings Results of population genetic structure and demographic history analyses showed that this endangered fir group has diverged into two lineages corresponding to A.beshanzuensis and A.ziyuanensis.Abies ziyuanensis first diverged from the common ancestor of A.beshanzuensis and A.dayuanensis,the latter two split apart later and more closely related,forming the other lineage.The genetic diversity is low within these populations.Strong genetic differentiation was found among populations(fixation index,FST=0.083-0.208).Gene flow is not detected after lineages split,probably because of the fragmented habitats which blocked effective genetic exchanges among populations.Ecological niche comparison showed that the average annual temperature and the temperature of the coldest quarter were significantly higher in the habitats of these endangered firs compared to those of non-threatened firs in East Asia.Therefore,we inferred that global warming is likely to push this group of endangered firs to the edge of extinction.According to the significant population differentiation,we provide genetic evidence that A.dayuanensis is a synonym of A.beshanzuensis,and resurrect

关 键 词：大院冷杉 溯祖分析 生态位 种群遗传学 物种保护 物种划分 靶向捕获测序 

分 类 号：Q948[生物学—植物学]