Page 100 - 《广西植物》2025年第12期
P. 100

2 2 4 2                                广  西  植  物                                         45 卷
                                           1ꎬ2ꎬ5            1          3                3
                               LEI Hanlin      ꎬ LI Ruozhu ꎬ CAI Jie ꎬ YANG Junbo ꎬ
                                                     3           3               1ꎬ2ꎬ4∗
                                   ZHANG Zhirong ꎬ LI Dezhu ꎬ YU Wenbin
            ( 1. Center for Integrative Conservation and Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephantsꎬ Xishuangbanna
               Tropical Botanical Gardenꎬ Chinese Academy of Sciencesꎬ Mengla 666303ꎬ Yunnanꎬ Chinaꎻ 2. Yunnan International Joint Laboratory for the
              Conservation and Utilization of Tropical Timber Tree Speciesꎬ Xishuangbanna Tropical Botanical Gardenꎬ Chinese Academy of Sciencesꎬ Mengla
                666303ꎬ Yunnanꎬ Chinaꎻ 3. The Germplasm Bank of Wild Speciesꎬ Kunming Institute of Botanyꎬ Chinese Academy of Sciencesꎬ Kunming
                        650201ꎬ Chinaꎻ 4. Southeast Asia Biodiversity Research Instituteꎬ Chinese Academy of Scienceꎬ Mengla 666303ꎬ
                                Yunnanꎬ Chinaꎻ 5. University of Chinese Academy of Sciencesꎬ Beijing 100049ꎬ China )

                 Abstract: The Malvatheca clade ( encompassing Malvoideae and Bombacoideae within Malvaceae s. l.) possesses
                 significant economic and ecological values. Howeverꎬ the phylogenetic relationships within this clade remain
                 controversialꎬ particularly concerning the phylogenetic placement of Fremontodendreaeꎬ Ochromeae and Matisieae.
                 Moreoverꎬ comprehensive analyses of plastome structural variations and evolution within this clade remain poorly
                 investigated. To resolve these research gapsꎬ this study incorporated the plastid whole genome (WGM) data from 142
                 species representing 8 tribes and 38 genera of the Malvatheca cladeꎬ including 77 plastomes newly de novo
                 assembled. We performed comparative genomic and phylogenetic analyses using the plastome datasets. The results were
                 as follows: (1) The plastome size in the Malvatheca clade exhibited variation ranging from 156 701 bp to 163 741 bpꎬ
                 primarily attributed to differential lengths in the inverted repeat ( IR) region and varying numbers of repetitive
                 sequences. (2) Four IR boundary types were identified through analysis of gene variation at IR/ SC junctions. The Type
                Ⅲa was inferred as the ancestral structure of the plastome within the Malvatheca cladeꎬ with identical IR expansion/
                 contraction events evolving convergently multiple times during its diversification. (3) Eight highly variable regions were
                 detected in both Malvoideae and Bombacoideaeꎬ with trnS GCU -trnG UCC ꎬ petA-psbJꎬ ndhD-ccsA and ycf1 being common to
                 both clades. Notablyꎬ trnS GCU  - trnG UCC ꎬ ycf1 and the commonly used molecular markers ndhF exhibited robust
                 phylogenetic resolution. (4) The topologies inferred from both the plastid WGM matrix and protein coding sequence
                 (CDS) matrix datasets were largely identical and well ̄resolvedꎬ and provided a reliable phylogenetic framework for
                 Malvatheca clade. The result showed that the Malvatheca clade was divided into four lineagesꎬ with Fremontodendreae as
                 the earliest divergent groupꎬ followed by Ochromeaeꎬ then Bombacoideae and Malvoideae formed as sister group.
                 Additionallyꎬ our results revealed non ̄monophyly in tribes Adansonieae and Bombaceaeꎬ as well as the genera Sida and
                 Hisbiscus. The composition and taxonomic treatment of these groups still require further research. This study clarifies
                 critical phylogenetic relationships within the Malvatheca clade while providing new perspectives on the plastome
                 characteristics and evolution through the most extensively sampled plastome dataset currently available for this clade.
                 Key words: Malvatheca cladeꎬ phylogenyꎬ plastomeꎬ Bombacoideaeꎬ Malvoideaeꎬ Malvaceae



                  分 子 系 统 学 研 究 建 立 了 广 义 锦 葵 科                有很多具有重要的经济价值和生态意义的物种ꎬ
            (Malvaceae sensu lato) 的系统框架ꎬ包含了传统的                一直备受关注ꎮ 整体上ꎬ锦葵亚科作为一个全球
            木棉科(Bombacaceae)、梧桐科(Sterculiaceae) 及椴             广布的类群ꎬ包括约 78 属超过 1 800 种( Stevensꎬ
            树 科 ( Tiliaceae) ( Alverson et al.ꎬ 1999ꎻ Bayer et  2001)ꎬ多为灌木或草本ꎬ其成员如棉( Gossypium
            al.ꎬ 1999)ꎮ 广义锦葵科内 9 个主要分支现已划分                     hirsutum L.)、 秋 葵 [ Abelmoschus esculentus ( L.)

            为 9 个 亚 科ꎬ 并 得 到 了 广 泛 的 认 可 ( Stevensꎬ            Moench] 是 重 要 的 经 济 作 物ꎬ 而 木 槿 属 ( Hibiscus
            2001)ꎮ 值得注意的是ꎬ系统发育分析揭示锦葵亚                          L.)物种是全球广泛栽培的观赏植物ꎮ 相较之下ꎬ
            科(Malvoideae)和木棉亚科(Bombacoideae)构成一                木棉亚科约含 17 属 164 种ꎬ多为热带森林中冠层
            个高度支持分支ꎬ被命名为 Malvatheca 分支ꎮ 该分                     优势物种ꎬ典型代表包括具有生态指示意义的木
            支整 合 了 传 统 分 类 学 中 的 锦 葵 科 与 木 棉 科                 棉(Bombax ceiba L.)ꎬ以及具有独特储水结构的猴
            (Bombacaceae)核心类群( Baum et al.ꎬ 1998)ꎬ拥            面包树(Adansonia digitata L.)ꎮ
   95   96   97   98   99   100   101   102   103   104   105