昆虫学报 ›› 2021, Vol. 64 ›› Issue (6): 730-742.doi: 10.16380/j.kcxb.2021.06.009

• 研究论文 • 上一篇    下一篇

中国南方双斑长跗萤叶甲地理种群遗传 结构及Wolbachia感染

李菁1, 张小飞2, 徐玲玲1, 申圆圆1, 李肖肖1, 王振营3,*   

  1.  (1. 西安文理学院生物与环境工程学院, 西安 710065; 2. 西安市农业技术推广中心, 西安 710061; 3. 中国农业科学院植物保护研究所, 北京 100193)
  • 出版日期:2021-06-20 发布日期:2021-06-15

Genetic structure and Wolbachia infection in geographical populations of Monolepta hieroglyphica (Coleoptera: Chrysomelidae) in South China

LI Jing1, ZHANG Xiao-Fei2, XU Ling-Ling1, SHEN Yuan-Yuan1, LI Xiao-Xiao1, WANG Zhen-Ying3,*   

  1. (1. School of Biological and Environmental Engineering, Xi′an University, Xi′an 710065, China; 2. Xi′an Agricultural Technology Extension Centre, Xi′an 710061, China; 3. State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China)
  • Online:2021-06-20 Published:2021-06-15

摘要:

【目的】双斑长跗萤叶甲Monolepta hieroglyphica为多食性害虫,可取食为害多种农作物。本研究旨在探究中国南方地区分布的双斑长跗萤叶甲地理种群的遗传多样性、遗传结构及种群间的遗传分化程度与基因流水平,探究共生菌Wolbachia在中国南方双斑长跗萤叶甲地理种群中的多样性和感染情况。【方法】以线粒体COII基因作为分子标记,对中国南方双斑长跗萤叶甲14个地理种群403头个体的COII基因片段进行PCR扩增及测序,分析单倍型多样性(Hd)、种群间遗传分化指数(Fst)和基因流(Nm),并进行分子方差分析 (AMOVA)以及Tajima’s DFu’s Fs中性检验,构建单倍型中介网络关系图及系统发育树。PCR扩增Wolbachiawsp基因,对供试种群进行Wolbachia感染率检测,并利用获得的wsp基因序列进行Wolbachia株系区分和系统发育分析。【结果】在供试的双斑长跗萤叶甲403头个体中共检测到23种COII基因单倍型,在系统进化上分成两大分支。总种群Hd为0.748,各种群的Hd在0.394~0.782间。中性检验结果表明种群在进化上遵循中性模型,在较近的历史时期内没有经历明显的群体扩张事件。总种群的Fst为0.2481,Nm为0.76,AMOVA结果表明种群间的遗传分化主要来自种群内部,占方差比率的73.75%。种群间的遗传距离与地理距离间无显著相关性(R=0.2898,P=0.0640)。14个地理种群的Wolbachia感染率在92.59%~100%之间,平均感染率为97.60%;基于wsp基因序列,在检测的感染个体中共发现6种Wolbachia株系(wMhie1~ wMhie6),均属于A大组,这6种株系与已知的代表性株系区别明显而在系统发生树中单独聚为一个分支。【结论】中国南方双斑长跗萤叶甲种群遗传多样性较高,多数种群间存在明显的遗传分化,种群间基因交流较低,遗传分化与地理隔离之间无显著相关性。Wolbachia在中国南方双斑长跗萤叶甲种群中具有很高的感染率及丰富的感染类群。

关键词: 双斑长跗萤叶甲, 地理种群, COII, 单倍型, 遗传结构, Wolbachia

Abstract:  【Aim】 Monolepta hieroglyphica is a polyphagous pest feeding on a large number of cultivated plant species. The aim of this study is to investigate the genetic diversity, genetic structure, and levels of genetic differentiation and gene flow among geographical populations of M. hieroglyphica distributed in South China, and to clarify the diversity and prevalence of the bacterial endosymbiont Wolbachia in M. hieroglyphica geographical populations in South China. 【Methods】 The mitochondrial COII gene was used as genetic marker. The partial COII gene sequences in a total of 403 individuals from 14 geographical populations of M. hieroglyphica were amplified by PCR and sequenced. The haplotype diversity (Hd), genetic differentiation coefficient (Fst) and gene flow (Nm) between populations were analyzed, and the analysis of molecular variance (AMOVA) and Tajima’s D and Fu’s Fs neutrality tests were performed. Median-joining network and phylogenetic tree were constructed based on haplotype sequences. Wolbachia wsp gene was amplified by PCR to detect population infection rates, and the obtained wsp sequences were used for strain typing and phylogenetic analysis of Wolbachia. 【Results】 For all the 403 test individuals of M. hieroglyphica in this study, 23 COII haplotypes were observed and divided into two clusters in phylogenetic tree. The Hd of total population was 0.748, ranging from 0.394 to 0.782 within each population. The neutrality test results suggested that M. hieroglyphica populations followed the neutral evolution model and there was no evidence of population expansion in recent history. The values of Fst and Nm of total population were 0.2481 and 0.76, respectively. The AMOVA results showed that a high proportion (73.75%) of the total genetic variance attributed to variation within population. There was no significant correlation between genetic distance and geographical distance among populations (R=0.2898, P=0.0640). The Wolbachia infection rates in the 14 geographical populations of M. hieroglyphica ranged from 92.59% to 100%, with an average infection rate of 97.60%. Six Wolbachia strains (named as wMhie1-wMhie6) were identified based on wsp sequences, and these strains all belong to the supergroup A, which is clearly distinguished from other representative stains and forms a unique cluster in the phylogenetic tree. 【Conclusion】 The genetic diversity of M. hieroglyphica populations distributed in South China is comparatively high. There is significant genetic differentiation among most populations and the gene flow is low among populations. No significant correlation exists between genetic differentiation and geographical isolation. High infection rates and diversity of Wolbachia exist in M. hieroglyphica populations in South China.

Key words: Monolepta hieroglyphica, geographical population, COII, haplotype, genetic structure, Wolbachia