基于mtDNA CO Ⅰ和mtDNA CO Ⅱ分子标记的贵州省茶棍蓟马种群遗传多样性分析

Genetic diversity among populations of Dendrothrips minowai Priesner in Guizhou based on mtDNA CO Ⅰ and mtDNA CO Ⅱ molecular markers

【目的】研究贵州省茶棍蓟马不同地理种群间的遗传多样性,为掌握贵州省茶棍蓟马的遗传动态和扩散规律及制定防控措施提供理论依据。【方法】以贵州省11个不同地理区域的茶棍蓟马种群mtDNA CO Ⅰ和mtDNA CO Ⅱ基因序列为靶标,利用MEGA 6.0、DnaSP 5.10、Arlequin 3.5.2.2和Network 2.0等软件对种群遗传分化、基因流水平、分子变异及种群遗传多样性等进行分析。【结果】基于mtDNA CO Ⅰ和mtDNA CO Ⅱ基因分析时,分别检测到11种和9种单倍型,各地理种群的单倍型多样度(Hd)较高,分别为0.609和0.633;总体遗传固定指数(FST)分别为0.11902和0.09052,基因流(Nm)分别为2.00和2.51,表明贵州省茶棍蓟马各地理种群间的基因交流水平较高,种群间遗传分化较小。mtDNA CO Ⅰ和mtDNA CO Ⅱ基因序列的单倍型网状树分析均无明显分支;种群间的分子变异(AMOVA)分析结果表明,茶棍蓟马的遗传变异主要来自种群内部。总群体的中性检验Fu’s Fs不显著(P>0.05),且错配分布曲线呈现多峰,说明贵州省茶棍蓟马种群在较近的历史时期内保持相对稳定,未经历明显的种群扩张,或处于临界状态。【结论】贵州省茶棍蓟马种群遗传多样性较丰富,虽然尚未形成明显的种群扩张,但可能已处于临界状态,应积极采取综合防控措施,力争将茶棍蓟马种群数量控制在危害水平以下,以保证贵州省茶产业生产健康可持续发展。

【Objective】The study was conducted to investigate genetic diversity among different geographical populations of Dendrothrips minowai Priesner in Guizhou,so as to provide theoretical foundation for the analysis of population genetic dynamics,population dispersion mechanism and formulating control measures.【Method】The mtDNA CO Ⅰ and mtDNA CO Ⅱ sequences of D. minowai populations,which collected from 11 different geographical areas in Guizhou,were selected as molecular markers,population genetic differentiation,gene flow,molecular variance and genetic diversity of populations were analyzed by using software MEGA 6.0,DnaSP 5.10,Arlequin 3.5.2.2,Network 2.0 etc.【Result】A total of 11 and 9 types of haplotype were detected when the mtDNA CO Ⅰ and mtDNA CO Ⅱ gene were analyzed,respectively,haplotype diversity(Hd)of different geographic population were high,which were 0.609 and 0.633,respectively. The total genetic fixations index(FST)were 0.11902 and 0.09052,the total gene flow(Nm)were 2.00 and 2.51,respectively,which indicated that the level of gene communication was high and the genetic differentiation among populations were small. The haplotype network of different geographical populations based on mtDNA CO Ⅰ and mtDNA CO Ⅱ showed no obvious branches,and the analysis of molecular variance(AMOVA)of different geographical populations indicated that the genetic variation mainly occurred within the same population. The total neutral test showed that Fu’s Fs were not significant(P>0.05),and the mismatch distribution curve had multiple peaks,which indicated the population of D. minowai in Guizhou were relatively stable in recent historical period,and has not experienced evident expansion or at critical state.【Conclusion】The genetic diversity of D. minowai populations in Guizhou is relatively rich,which has not yet formed an obvious sudden expansion,but might approach to critical phase. Therefore,comprehensive prevention and control measures should be taken actively to control the D. minowai populations quantity under damage level and ensure the sustainable and healthy development of tea production in Guizhou.