海南省油茶及其他寄主植物果生刺盘孢菌群体遗传结构分析  

Population Genetic Structure of Colletotrichum fructicola from Oil-Tea and Other Host Plants in Hainan province

作　　者：李河[1,2] 李杨[1] 徐建平[1,2] 周国英[1,2] 

机构地区：[1]森林有害生物防控湖南省重点实验室,中南林业科技大学,长沙410004 [2]经济林培育与保护教育部重点实验室,中南林业科技大学,长沙410004

出　　处：《林业科学》2016年第10期80-88,共9页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目(31570641;31100479)

摘　　要：【目的】研究海南省油茶树及其他寄主植物炭疽病菌果生刺盘孢菌群体遗传结构、群体遗传多样性及单倍型地理分布,探索海南地区不同寄主植物炭疽病菌的分子遗传变异规律。【方法】利用单孢分离法对采集自海南省南圣镇、通什镇、枫木林场和澄迈林场4个地区9种不同寄主植物的炭疽病病叶进行炭疽菌分离,并对每个菌株ITS,CAL和GAPDH 3个基因进行PCR扩增和测序,按顺序对3个基因的序列进行拼接,然后采用Gen ALEx6,Dna SP 5.0,TCS1.21和MEGA6.0软件分别对数据进行分析。【结果】分离、鉴定共获得12个病菌种群的108个果生刺盘孢菌病菌样品,可推导出18种单倍体型(haplotype),其中单倍型Haplotype11共70个菌株,为优势单倍型,在每个病菌种群中均有分布;单倍型网络结构分析表明,病原菌以单倍型Haplotype11为辐射中心,呈现出1个比较典型星状发散图,推测Haplotype11为原始单倍型;108株病菌表现出丰富的遗传多样性;AMOVA分析显示,种群间和种群内的遗传变异分别占总变异的3%和97%,变异主要存在种群内,而种群间的差异小,说明不同的寄主植物未对病菌交流造成隔离障碍;遗传分化和基因流分析发现,12个病菌种群间遗传分化小,种群间基因交流频繁;另外,油茶种群之间以及油茶与鲫鱼胆、葛根和山矾等植物种群之间的果生刺盘孢菌存在遗传重组现象;系统发育分析表明,来自同一个果生刺盘孢菌种群的单倍型未能聚在一起,而是散乱的分布在系统树中,没有显示出明显的寄主植物分布族群;核苷酸不配对分析表明病菌种群历史上并没有发生显著的种群扩张。【结论】海南省果生刺盘孢菌遗传多样性丰富,不同地区和不同寄主植物病菌种群之间存在有效基因流,揭示该病菌可以在油茶树及其他寄主植物之间迁移,这为整体考虑海南省油茶及其他寄主植物制定可持续控制油茶炭疽病策略【Objective】The population genetic structure genetic diversity and the geographical distribution of haplotype patterns of Colletotrichum fructicola from Oil-tea and other host plants in Hainan province were analysised to explore the molecular genetic variation pattern of the pathogen in different hosts.【Method】C. fructicola associated with anthracnose diseases of oil-tea and other native plants were isolated using single spore isolation and confirmed by DNA sequencing of the partial sequences of r DNA-ITS,CAL and GAPDH region. Gen ALEx6,Dna SP 5. 0,TCS1. 21 and MEGA6. 0 software was used to analyze the data of ITS-CAL-GAPDH sequences.【Result】A total of 108 strains was isolated,and 18 haplotypes were identified. The most common sequence type,haplotype 11,was found in 70 samples and distributed across all populations.AMOVA test showed that 3% of genetic differentiation occurred among populations and 97% within population. There was avery low genetic divergence in Fst and Nm values among the populations and the high level of gene flow was among populations. There existed genetic recombination among some populations of C. fructicola from Oil-tea camellia and the other host plants. 【Conclusion 】Results of this research illustrates that there exists high degree of genetic intermixing among natural populations of C. fructicola. Our study provides a foundation that a more holistic approach would be needed to take into account of the life histories of different hosts in order to develop effective strategies for controlling anthracnose.

关 键 词：油茶 寄主植物 果生刺盘孢菌 群体遗传结构 

分 类 号：S763.1[农业科学—森林保护学]