玉米大斑病菌UP-PCR体系的建立和遗传多样性分析  

Establishment of UP-PCR System and Genetic Diversity Analysis of Exserohilum turcicum

作　　者：高金欣[1,2] 高增贵[1] 吕淑霞[2] 张秀霞[1] 庄敬华[1] 张硕[1] 

机构地区：[1]沈阳农业大学植物免疫研究所,沈阳110866 [2]沈阳农业大学生物科学技术学院,沈阳110866

出　　处：《玉米科学》2011年第6期112-117,共6页Journal of Maize Sciences

基　　金：国家"十一五"科技支撑项目(2006BAD08A06);辽宁省教育厅攻关项目(2004D220);辽宁省教育厅重点实验室项目(LS2010149);国家粮丰工程(2011BAD16B12)

摘　　要：对通用引物PCR(UP-PCR)扩增反应中的dNTP、引物、MgCl2、DNA聚合酶和模板浓度以及退火温度(Tm)、PCR反应循环数等重要参数进行摸索和优化,建立适合玉米大斑病菌(Exserohilum turcicum)的UP-PCR反应体系,并筛选出7条多态性较好且稳定的引物。对来自辽宁、吉林、黑龙江玉米主产区的24株病菌进行UP-PCR分析,共扩增出75条谱带,大小介于250～2 000 bp,多态性比率为72.0%,说明UP-PCR标记在玉米大斑病菌中存在较高的多态性。聚类分析显示,在阈值为0.796处菌株被分为8个类群。东北地区玉米大斑病菌群体存在明显的种内遗传分化现象,菌株的遗传多样性和地理来源无明显的相关性,和生理小种组成有一定的相关性,但并不是遗传谱系就等于生理小种的简单对应关系。UP-PCR技术可以充分展现玉米大斑病菌菌株间的亲缘关系及差异性,可为有效地开展玉米大斑病菌的遗传进化及探讨其致病性的生理分化提供一种新的方法。A suitable Universally Primed PCR （UP-PCR） amplification system was established and optimized in the dNTP, primers, MgCl2, Taq DNA polymerase and DNA template concentration. Melting temperature （Tm） and the number of amplification cycles were optimized as well. Seven polymorphic primers were screened to study the genetic diversity among 24 isolates of Exserohilum turcicum coming from the major corn planting areas in the Northeast of China. A total of 75 bands ranged between 250 bp and 2 000 bp were amplified among the tested isolates,and 72.0% were found to be polymorphic, indicating the high genetic diversity in the population of E. turcicum. The dendrogram based on UP-PCR results revealed that the 24 isolates were clustered into 8 groups at the threshold of genetic similar coefficient of 0.796. All above results indicated that there was abundant genetic diversity among E. turcicum colony in the Northeast of China;there was no distinct relationship between the fungal genetic diversity and their geographic distribution;there was some correlation between fungal genetic diversity and physiological races but not simple genetic pedigree-races relationship between them. UP-PCR analysis revealed the phylogenetic relationships and difference of the tested isolates of E. turcicum,which provided a new method for analyzing the genetic evolution and the physiological differentiation of E. turcicum.

关 键 词：玉米 大斑病菌 聚类分析 地理来源 生理小种 

分 类 号：S435.131[农业科学—农业昆虫与害虫防治]