Page 148 - 《广西植物》2025年第3期
P. 148

5 2 8                                  广  西  植  物                                         45 卷
                 Abstract: Camellia sinensis var. sinensis ‘Liupao’ is the main raw material for making Liupao tea. To explore the
                 genetic background of C. sinensis var. sinensis ‘Liupao’ꎬ especially its phylogenetic position and evolutionary historyꎬ
                 27 individuals of C. sinensis var. sinensis ‘ Liupao’ and five individuals of C. costata were sampled for genome
                 skimming and transcriptomic sequencing. The phylogenetic relationshipꎬ the divergence evolution timeꎬ and the
                 genetic diversity of C. sinensis var. sinensis ‘ Liupao’ were analyzed. The results were as follows: ( 1) On the
                 chloroplast treeꎬ samples of C. sinensis var. sinensis ‘Liupao’ were divided into two distantly ̄related groupsꎬ one was
                 nested within a clade mainly consisting of C. sinensisꎬ being interspersed among other cultivated C. sinensisꎬ while the
                 other group formed as a well supported lineage that was most closely ̄related to and nested within C. costataꎻ on the
                 nuclear gene treeꎬ howeverꎬ all the 27 samples of C. sinensis var. sinensis ‘ Liupao’ formed a clade with other C.

                 sinensis as well as some other Camellia species with generally unresolved relationships among them. Despite the lack of
                 resolution in this cladeꎬ it was definitely far separated from C. costataꎻ the cytonuclear phylogenetic conflict suggested
                 once ancient introgression hybridization of C. costata with the ancestor of some C. sinensis var. sinensis ‘ Liupao’
                 individuals so that the latter captured the chloroplast genome of the former. (2) The time estimate further indicated
                 that the introgression hybridization event occurred in the Quaternary periodꎬ ca. 1.55 million years agoꎬ long before the
                 history of tea cultivation and production by humans. (3) In additionꎬ both the chloroplast genomes and nuclear genes
                 revealed that the C. sinensis var. sinensis ‘ Liupao’ had high haplotype diversityꎬ possessing high evolutionary
                 potential. This study provides the references for the germplasm protectionꎬ variety breedingꎬ development and
                 utilization of C. sinensis var. sinensis ‘Liupao’.
                 Key words: Camellia sinensis var. sinensis ‘ Liupao’ꎬ chloroplast genomesꎬ transcriptomesꎬ chloroplast genome
                 captureꎬ hybridizationꎬ genetic diversity



                广 义 的 茶 树 指 山 茶 科 ( Theaceae) 山 茶 属            由此推测ꎬ该茶树在三倍化过程中发生了叶绿体
            (Camellia)茶组( Sect. Thea) 植物ꎬ而狭义的茶树                转移ꎬ即通过渐渗杂交捕获了其他物种的叶绿体ꎮ
            则指茶(Camellia sinensis) 这一种( 含变种、变型等                虽然叶绿体基因已广泛应用于山茶属植物系统发
            种下等级)植物( 杨世雄ꎬ2021a)ꎮ 茶包含了众多                        育和遗传多样性研究( 叶晓倩等ꎬ 2014ꎻLi et al.ꎬ
            品种或地方种ꎬ具有不同的风味品质ꎮ 茶的不同                             2021ꎻ闫明慧等ꎬ2021)ꎬ但是叶绿体基因组通常为
            品种以及山茶属其他种类被认为存在频繁的杂交                              母系遗传ꎬ单独使用无法准确解析杂交或基因渐

            和多 倍 化ꎬ 具 有 复 杂 的 演 化 历 史 ( Huang et al.ꎬ          渗等网状演化ꎬ而利用核低拷贝直系同源基因序
            2013ꎻWang et al.ꎬ 2020ꎻZan et al.ꎬ 2023)ꎮ 例如ꎬ      列则已成功解决了许多疑难的系统发育尤其复杂
            山茶( C. japonica) 和短柄山茶( C. rusticana) 之间           的网 状 演 化 问 题 ( Yang et al.ꎬ 2015ꎻ Wu et al.ꎬ

            能 发 生 自 然 杂 交 ( Ueno & Tsumuraꎬ 2009 )ꎮ            2022ꎻZan et al.ꎬ 2023)ꎮ
            Meegahakumbura 等(2016)对 392 份茶样品的遗传                    广西茶树种质资源极为丰富ꎬ根据闵天禄的茶
            分析发现 30%的样品具有不同类型茶树的遗传混                            组分类系统ꎬ茶组共包含 12 种 6 变种ꎬ而广西有 8

            合ꎬ表明它们为杂交起源ꎬ其中柬埔寨茶( Cambod                         种ꎬ是中国茶组植物资源最丰富的地区 ( Ming &
            tea)就被认为是 阿 萨 姆 茶 ( Assam tea) 和 中 国 茶             Bartholomewꎬ 2007ꎻ杨世雄ꎬ2021b)ꎮ 广西也拥有很
            (China tea)的杂交品种ꎮ 李苗苗等(2015) 利用核                   多历史悠久的地方品种及名茶(陈宗懋ꎬ1992)ꎬ其

            基 因 微 卫 星 标 记 对 普 洱 茶 ( C. sinensis var.           中广西梧州的六堡茶ꎬ为中国二十四大名茶之一ꎬ
            assamica)和大理茶(C. taliensis) 进行 STRUCTURE           以其“红、浓、陈、醇”及独特的槟榔香特点闻名于世
            聚类分析ꎬ发现在混栽的大理茶和普洱茶居群间ꎬ                             (陈佳等ꎬ2020)ꎮ 六堡茶群体种是制作六堡茶的主
            存在由大理茶向普洱茶的基因渐渗ꎮ Li 等(2021)                        要原材料ꎮ 根据«中国茶树品种志»中的相关记载ꎬ
            研究发现武夷菜茶水仙茶树品种(三倍体) 和山茶                            六堡茶群体种为广西地方有性系茶树品种ꎬ为中叶
            属其他 4 个物种在 trnE-trnT 间隔区具有同样 335                   种ꎬ主要分布在广西苍梧、贺县、蒙山和昭平等地
            bp 的序列缺失ꎬ但 292 份栽培茶都没有缺失这段ꎮ                        (中国茶树品种志编写委员会ꎬ2001)ꎮ 对六堡茶群
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