Page 29 - 《广西植物》2026年第4期
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4 期                 张晟等: 贵州九种猕猴桃属植物叶绿体基因组特征及比较分析                                            5 8 7

                 Abstract: To elucidate the chloroplast genomic characteristics and phylogenetic relationships within the genus Actinidiaꎬ
                 nine species distributed in Guizhou Provinceꎬ including A. polygamaꎬ A. rubricaulis var. coriaceaꎬ and A. callosa
                 var. henryiꎬ were selected in this study. Based on next ̄generation sequencing dataꎬ we performed chloroplast genome
                 assemblyꎬ annotationꎬ and comparative genomic analysis to systematically investigate their genomic characteristics and
                 phylogenetic relationships. The results were as follows: (1) The chloroplast genomes of all nine Actinidia species were
                 double ̄stranded circular molecules with a typical quadripartite structure. Their full lengths ranged from 155 660 to
                 156 770 bpꎬ and the overall GC content varied from 37.21% to 37.33%ꎬ indicating high similarity in genome size. (2)
                 A total of 130 genes were annotated in most speciesꎬ including 83 protein ̄coding genesꎬ 39 tRNA genesꎬ and 8 rRNA
                 genesꎬ except that 129 genes were annotated in A. fulvicoma and A. fortunatii. (3) Codon usage bias was similar among
                 speciesꎬ with a preference for A/ U at the third codon position. A total of 491 simple sequence repeat (SSR) loci were
                 identifiedꎬ encompassing six repeat types ranging from mononucleotide to hexanucleotide. (4) Comparative genomic
                 analysis revealed that sequence variation was higher in the large single copy (LSC) and small single copy (SSC) regions
                 than in the inverted repeat (IR) regionꎬ and that non ̄coding regions exhibited more pronounced variation than coding
                 regions. Nine divergent gene fragments were identifiedꎬ including intergenic spacers such as rps16-trnQ ̄UUGꎬ ndhC-
                 trnV ̄UACꎬ and the rbcL-accD region. (5) Phylogenetic analysis resolved the nine species into four clades: A. polygama
                 was phylogenetically distant from the othersꎻ A. chinensis and A. chinensis var. deliciosa clustered togetherꎻ A. callosa
                 var. henryiꎬ A. rubricaulis var. coriaceaꎬ A. fortunatiiꎬ and A. fulvicoma formed a distinct cladeꎻ and A. latifolia showed
                 the closest relationship with A. eriantha. This study provides an important basis at the chloroplast genome level for the
                 identification and conservation of kiwifruit germplasm resources in Guizhou Provinceꎬ and also accumulates key data and
                 a theoretical basis for the taxonomyꎬ phylogeny and molecular identification of this genus.
                 Key words: Actinidiaꎬ chloroplast genomeꎬ simple sequence repeatsꎬ sequence alignmentꎬ phylogeny



                猕猴桃为猕猴桃科( Actinidiaceae) 猕猴桃属                  野生资源开展系统比较与进化分析ꎬ对厘清猕猴
            (Actinidia Lindl.)多年生藤本植物ꎬ驯化历史仅百                   桃属植物的分类关系、促进省内种质资源的科学
            余年ꎮ 全球的猕猴桃属植物约有 54 个种和 21 个                        保护与可持续利用具有重要意义ꎮ

            变种(Li et al.ꎬ 2007)ꎬ自然分布在以中国为中心ꎬ                       叶绿体是植物光合作用的关键细胞器ꎬ不仅
            南起赤道、北至寒温带(北纬 50°)的亚洲东部地区                          参与淀粉、脂肪酸、色素和氨基酸的生物合成ꎬ也
            (黄宏文等ꎬ2013)ꎮ 贵州省地处中国西南ꎬ其复杂                         是代谢与能量转换的重要场所ꎮ 其基因组通常为
            的地貌与多样的小气候为野生猕猴桃提供了丰富                              环状双链 DNA 结构ꎬ具有相对保守的组成、单亲
            的生境ꎮ 野生猕猴桃常见于山坡杂木林、溪边灌                             遗传模式以及丰富的变异位点ꎬ因此被广泛用于
            丛及林缘路旁等地ꎬ这也使贵州成为我国野生猕                              植物系统发育重建、物种鉴定和遗传多样性分析
            猴桃资源的重要分布区之一( 刘磊等ꎬ2015)ꎮ 我                         等研究中( Nock et al.ꎬ 2011ꎻ Shi et al.ꎬ 2023)ꎮ
            国丰富的猕猴桃资源为系统开展进化研究与遗传                              近年来ꎬ随着测序技术的发展ꎬ猕猴桃叶绿体基因
            育种工作提供了宝贵的材料( Liu et al.ꎬ 2010)ꎬ这                  组研究取得了一系列重要进展ꎮ 目前ꎬ已陆续报
            使当下仅以中华猕猴桃(A. chinensis)、美味猕猴桃                     道了中华( Yao et al.ꎬ 2015b)、山 梨 ( Kim et al.ꎬ
            (A. chinensis var. deliciosa)等少数种类为主要的商            2018)、长叶( Qi et al.ꎬ 2021)、阔叶( Yang et al.ꎬ
            业化栽培格局更加丰富(Mai et al.ꎬ 2022)ꎮ 然而ꎬ                  2021)、毛花( Yao et al.ꎬ 2022)、狗枣( Qiu et al.ꎬ
            该属植物种间杂交频繁且广泛( Li et al.ꎬ 2014)ꎬ                   2021)等猕猴桃物种的完整叶绿体基因组ꎬ为揭示
            染色体倍性变异复杂(Shi et al.ꎬ 2010)ꎬ仅凭外观                   该属植物的遗传背景与进化关系提供了重要依
            形态和生理特征难以准确鉴定ꎬ给分类学研究带                              据ꎮ 基于叶绿体基因组的系统发育分析表明ꎬ美
            来了较大困难ꎮ 因此ꎬ有必要提供更多的基因组                             味猕猴桃、中华猕猴桃、黑蕊猕猴桃和硬齿猕猴桃
            资源ꎬ以探索猕猴桃属内的系统发育关系( Zhang                          亲缘关系较近(Liu et al.ꎬ 2022)ꎮ 然而ꎬ目前针对
            et al.ꎬ 2025)ꎮ 在此背景下ꎬ利用贵州省内丰富的                     贵州地区野生猕猴桃资源的叶绿体基因组研究仍
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