Page 48 - 广西植物2024年1期
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4 4 广 西 植 物 44 卷
( 1. Centre for Gardening and Horticultureꎬ Xishuangbanna Tropical Botanical Gardenꎬ Chinese Academy of Sciencesꎬ Mengla 666300ꎬ Yunnanꎬ
Chinaꎻ 2. School of Landscape Architectureꎬ Southwest Forestry Universityꎬ Kunming 650224ꎬ Chinaꎻ 3. Southwest Landscape Architecture
Engineering Technology Research Centerꎬ State Forestry and Grassland Administrationꎬ Kunming 650224ꎬ Chinaꎻ 4. Orchid
Conservation & Research Center of Shenzhen and the National Orchid Conservation Center of Chinaꎬ Shenzhen Key
Laboratory for Orchid Conservation and Utilizationꎬ Key Laboratory of National Forestry and Grassland
Administration for Orchid Conservation and Utilizationꎬ Shenzhen 518114ꎬ Guangdongꎬ China )
Abstract: Pecteilis susannae and P. hawkesiana are rare and endangered species with important medicine and ornament
value. Howeverꎬ little is known about the genetic information of these two species. In order to understand the basic
characteristics of the chloroplast genome of these two Pecteilis speciesꎬ and to develop molecular markers for species
identificationꎬ conservation genetic and phylogenetic analysisꎬ the genome skimming approach using next ̄generation
sequencing methods was used to generate chloroplast DNA sequences in this study. The chloroplast genomes were
assembled and annotated by bioinformatics analysis. Simple sequence repeats (SSRs)ꎬ single nucleotide polymorphisms
(SNPs)ꎬ and insertions and deletions ( InDels) were identified. Furthermoreꎬ comparative chloroplast genomic and
phylogenetic analyses were conducted with closely related species. The results were as follows: (1) The newly sequenced
chloroplast genomes of P. susannae and P. hawkesiana were 154 407 bp and 153 891 bp in size. They comprised a pair of
26 550 bp and 26 523 bp inverted repeats (IR) that separated a large 84 204 bp and 83 756 bp single copy region
(LSC) and a small 17 103 bp and 17 089 bp single copy region ( SSC)ꎬ respectively. Both chloroplast genomes
contained 111 unique genesꎬ including 77 protein ̄coding genesꎬ 30 tRNA and 4 rRNA genes. (2) Ninety ̄four simple
sequence repeats (SSRs) were identified in the P. susannae chloroplast genome and 92 in that of P. hawkesiana. (3)
Comparisons of two chloroplast genomes revealed that there were nucleotide variations including 706 single ̄nucleotide
polymorphism sites and 152 InDels between the two Pecteilis speciesꎬ of which several markers (cpInDel 067) could
discriminate the two Pecteilis species. (4) The one most divergent gene (accD) and the nine most divergent intergenic
regions (rps19-psbAꎬ matK-trnQ ̄UUGꎬ psbM-psbDꎬ trnT ̄UGU-ndhJꎬ accD-psaIꎬ ycf4-cemAꎬ clpP-psbBꎬ ndhF-
trnL ̄UAGꎬ rps15-ycf1) among genomes were detected. (5) The phylogenetic analysis based on the chloroplast genome
sequences revealed that P. susannaeꎬ P. hawkesiana and Habenaria dentata are closely related. The molecular markers
(SSRsꎬ InDels and hotspots) developed from the chloroplast genomes of two Pecteilis species in the present study can be
used to identify related species and provide valuable genetic resources in utilizing and conserving natural resources.
Key words: Pecteilis susannaeꎬ P. hawkesianaꎬ chloroplast genomeꎬ molecular markersꎬ phylogeny
白 蝶 兰 属 ( Pecteilis) 为 地 生 兰ꎬ隶 属 于 兰 科 龙头兰(P. susannae)是白蝶兰属的模式种ꎬ也
(Orchidaceae)红门兰亚科(subfamily Orchidoideae) 称白蝶花ꎬ从东喜马拉雅一直到东南亚和马来半
红门兰 族 ( tribe Orchideae) 红 门 兰 亚 族 ( subtribe 岛都有分布(Wah et al.ꎬ2021)ꎮ 在我国ꎬ龙头兰广
Orchidinae)ꎬ全世界约有 10 种ꎬ主要分布于亚洲热 泛分布于南部和西南部各省区ꎬ生长于海拔 500 ~
带 至 亚 热 带 地 区 ( Jin et al.ꎬ 2014ꎬ 2017ꎻ Teohꎬ 2 500 m 的山坡林下开阔地、沟边和草坡( Wu et
2021)ꎮ 长期以来ꎬ白蝶兰属与红门兰亚族的玉凤 al.ꎬ2009)ꎮ 虽然龙头兰在我国分布范围广ꎬ但近
花属( Habenaria) 系统发育关系不清( Pridgeon et 年来ꎬ生境丧失和过度采挖导致野生种群数量急
al.ꎬ2001)ꎮ 2 个属在形态学方面的关键区别在于 剧下降ꎮ 我国分布的白蝶兰属植物还包括滇南白
合蕊柱的结构:白蝶兰属的花药室具宽的药隔ꎬ柱 蝶兰(P. henryi)、狭叶白蝶兰( P. radiate) 和景洪
头无柄附着在唇瓣基部ꎻ玉凤花属的花药室的药 白蝶兰( P. hawkesiana)ꎮ 景洪白蝶兰分布于东南
隔 较 窄ꎬ 柱 头 与 唇 瓣 基 部 之 间 形 成 柱 头 枝 亚热带地区ꎬ2015 年才在我国云南西双版纳自治
(stigmaphore)(Wah et al.ꎬ2021)ꎮ 此外ꎬ白蝶兰属 州发现有分布ꎬ个体数量极少ꎬ非常稀有(Li et al.ꎬ
的花通常比玉凤花属的大ꎬ唇瓣通常有较长的距ꎮ 2015)ꎮ 目前ꎬ我国白蝶兰属植物的野生资源的基
但是ꎬ根据最近的分子系统发育分析ꎬ白蝶兰属并 础调查尚不深入ꎬ遗传信息缺乏ꎬ极大地阻碍了对
非单系ꎬ嵌于玉凤花属中(Jin et al.ꎬ2014ꎬ2017)ꎮ 该属野生资源的保护和利用ꎮ