Page 33 - 《广西植物》2026年第1期
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1 期                   韦伶芝等: 凹脉金花茶的遗传多样性和群体遗传结构分析                                             2 9

                 Abstract: This study aimed to further elucidate the genetic diversity and population genetic structure of Camellia
                 impressinervisꎬ a species with extremely small populationsꎬ through the application of genotyping ̄by ̄sequencing
                 (GBS). A total of 56 individuals from four populations distributed across two nature reserves in Guangxiꎬ Chinaꎬ were
                 subjected to reduced ̄representation genome sequencingꎬ and comprehensive analyses of genetic diversity and population
                 genetic structure were conducted. To provide a scientific basis for the genetic conservation and effective protection of this
                 species. The results were as follows: (1) A total of 4 014 956 high ̄quality single ̄nucleotide polymorphism (SNP) loci
                 were identified across the 56 individualsꎬ with mean Q20 and Q30 values of 98.74% and 95.35%ꎬ respectivelyꎬ and GC
                 content ranging from 41.70% to 45.67%. (2) The Xialei Longheng population (CI ̄LH) exhibited the highest expected
                 heterozygosity (H = 0.201 4)ꎬ nucleotide diversity (P = 0.211 7) and inbreeding coefficient (F = 0.126 1). In
                              e                            i                                is
                 contrastꎬ the Nonggang Buna population (CI ̄BN) demonstrated the lowest observed heterozygosity (H = 0.171 6)ꎬ
                                                                                              o
                 nucleotide diversity (P = 0.180 3)ꎬ and inbreeding coefficient (F =-0.023 0). Estimates of gene flow intensity (N )
                                  i                              is                                   m
                 among populations varied between 1.151 3 and 4.557 7ꎬ with an average of 2.212 2. (3) Cluster analysisꎬ principal
                 component analysisꎬ and population genetic structure analysis collectively indicated that the 56 samples of C.
                 impressinervis could be grouped into four distinct clusters. In conclusionꎬ C. impressinervis exhibits moderate levels of
                 genetic diversity and genetic differentiation. It is recommended to strengthen in ̄situ conservation for the CI ̄BN
                 populationꎬ and when feasibleꎬ implement reintroduction to promote population recovery and expansion. Additionallyꎬ
                 enhancing habitat protection and prohibiting on artificial excavation are crucial for maintaining its genetic diversity. The
                 research results provide a scientific basis for the genetic conservation and effective protection of C. impressinervis.
                 Key words: Camellia impressinervisꎬ genotyping ̄by ̄sequencing( GBS)ꎬ extremely small population speciesꎬ genetic
                 diversityꎬ population genetic structure



                生物多样性正面临着严峻的危机ꎬ目前有超过                           熊猫”ꎮ 近些年来ꎬ随着金花茶的价值被不断挖

            100 万个物种受到威胁ꎬ物种和种群数量持续下降ꎬ                          掘ꎬ凹脉金花茶野生资源被挖掘破坏十分严重ꎬ有
            在全球生物多样性丧失期间保护受威胁物种至关                              濒临灭绝的风险ꎮ 凹脉金花茶已被世界自然保护
            重要ꎻ濒危物种ꎬ尤其是那些种群较少的物种ꎬ由于                            联盟(IUCN)列为濒危物种( 覃海宁等ꎬ2017ꎻ赖彦
            气候 波 动 和 人 为 干 扰 而 面 临 很 高 的 灭 绝 风 险               池ꎬ2021ꎻ陈莹等ꎬ2022)ꎬ同时列入了« 国家重点保
            (Wariss et al.ꎬ 2025)ꎮ 物种的遗传结构和多样性在                护野生植物名录» ( 国家林业和草原局 农业农村
            其承受恶劣环境并随着时间推移而进化的能力中                              部ꎬ2021)ꎬ也是«全国极小种群野生植物保护工程
            起着关键作用(Zhang et al.ꎬ 2024)ꎮ 利用分子标记                 规划(2011—2015)»( 国家林业局 国家发展改革
            分析物种的遗传多样性与遗传结构可以明确居群                              委ꎬ2012)中优先保护的极小种群目标种之一ꎬ亟
            内及居群间的亲缘关系ꎬ了解物种的适应能力和进                             须对其开展有效保护ꎮ
            化潜力ꎬ特别是对于极小种群物种和稀有、濒危物                                 近年 来ꎬ 新 一 代 测 序 技 术 ( next ̄generation
            种ꎬ有助于分析其濒危的原因ꎬ为其保护策略的制                             sequencingꎬ NGS) 的快速发展提高了单核苷酸多

            定提供科学依据(Wang et al.ꎬ 2024)ꎮ                        态性( single ̄nucleotide polymorphismꎬ SNP) 的发现
                 凹脉金花茶( Camellia impressinervis) 属于山茶          效 率ꎬ 基 因 分 型 测 序 技 术 ( genotyping ̄by ̄

            科( Theaceae) 山 茶 属 金 花 茶 组 ( Camellia sect.        sequencingꎬ GBS)是一种基于 NGS 技术的 SNP 基
            Chrysantha)ꎬ是广西岩溶地区的特有物种( 文和群                      因分型方法( 张序等ꎬ2021)ꎮ GBS 技术可以迅速
            等ꎬ1993)ꎬ仅分布于广西崇左市的龙州县和大新                           鉴定出大量的高密度 SNP 标记ꎬ无需预先知道物
            县ꎬ其花色金黄ꎬ叶片大ꎬ椭圆形ꎬ叶脉多且凹陷明                            种基因组序列ꎬ成本较低、灵活简单ꎬ已经被广泛
            显ꎬ其枝条长度较短ꎬ分枝较多ꎬ是金花茶中具有                             用于遗传图谱的构建和分析、全基因组关联分析、
            很高观赏价值的种类( 梁盛业ꎬ1997ꎻ黄展文等ꎬ                          系统发育分析和遗传多样性分析等( Xiong et al.ꎬ
            2021)ꎮ 凹脉金花茶的黄色花瓣富含黄酮类化合                           2020ꎻChen et al.ꎬ 2022)ꎮ 目前ꎬGBS 技术已应用
            物ꎬ兼具药用潜力与观赏价值ꎬ被称为“ 植物界大                            于多种濒危植物遗传多样性分析中ꎮ 例如ꎬ周鑫
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