山西玉米丝黑穗病菌SSR遗传多样性与群体结构分析  

Assessment of genetic diversity and population structure of Sporisorium reilianum causing corn head smut using SSR markers in Shanxi

作　　者：李新凤[1] 尉天春 王雪梅[1] 姜晓东 杨俊伟[2] 冯铸 王建明[1] LI Xin-feng;YU Tian-chun;WANG Xue-mei;JIANG Xiao-dong;YANG Jun-wei;FENG Zhu;WANG Jian-ming(College of Plant Protection,Shanxi Agricultural University,Taigu 030801,China;Corn Research Institute,Shanxi Academy of Agricultural Sciences,Xinzhou 036200,China;Shanxi Agriculrure Seed Station,Taiyuan 030006,China)

机构地区：[1]山西农业大学植物保护学院,太谷030801 [2]山西省农业科学院玉米研究所,忻州036200 [3]山西省农业种子总站,太原030006

出　　处：《植物病理学报》2021年第6期921-933,共13页Acta Phytopathologica Sinica

基　　金：山西省应用基础研究项目(201701D121100);山西省重点研发计划项目(201803D221012-2、201703D221006-3、201903D211001-1)。

摘　　要：为明确山西省玉米丝黑穗病菌群体的遗传结构,为该病害的综合防控提供理论依据。采用SSR标记方法对山西省不同地区玉米丝黑穗病菌进行检测。结果显示,12个SSR分子标记在118株玉米丝黑穗病菌中共检测出30个等位基因,平均等位基因数(Na)、有效等位基因数(Ne)、Shannon’s信息指数(I)、等位基因丰度(Ar)分别为2.5、1.7686、0.6144和2.175。平均观测杂合度(Ho,0.1632)低于平均期望杂合度(He,0.3965),且近交系数(Fis,0.5221)大于0。说明本试验检测到的等位基因数较少,但分布比较均匀,且由于群体内的杂合子缺失导致病原菌群体显著偏离了Hardy-Weinberg。6个地理群体的遗传分化处于中等水平(FST=0.050~0.055),群体间基因交流频繁(Nm=1.563~121.109)。AMOVA分析结果进一步显示,遗传分化主要存在于群体内个体间(94.80%),群体间的变异仅占5.2%。UPGMA聚类结果表明,供试群体可被划分为遗传分化明显的两个亚群,其中位于晋东南地区的晋城群体和长治群体聚为一个组群,位于晋中和晋北地区的其余4个群体聚为另一组群,与遗传结构分析结果一致,推断山西省玉米丝黑穗病菌群体可能来自于2个祖先亚群,且大多数菌株的遗传组分单一。To clarify the genetic structure of Sporisorium reilianum population in Shanxi province,118 S.reilianum strains collected from 6 areas were analyzed by Simple Sequence Repeat(SSR)marker.A total of 30 alleles were detected using 12 pairs of primers.The mean number of alleles(Na),effective number of alleles(Ne),Shannon′s information index(I)and allele richness(AR)were 2.5,1.7686,0.6144 and 2.175,respectively.The mean observed heterozygosity(Ho,0.1632)was lower than the expected(He,0.3965),and the inbreeding coefficient was positive(Fis,0.5221).The results indicate a few alleles in the S.reilianum population,which was relatively uniform in Shanxi Province.Due to the heterozygote deficiency,the geographical populations significantly deviated from Hardy-Weinberg.The genetic differentiations of the six geographical populations were all at the medium level(FST=0.050-0.055),and genes of the populations exchanged frequently(Nm=1.563-121.109).Analysis of molecular variance(AMOVA)further showed that the genetic variation mainly occurred within the populations(94.80%),while only 5.2%among populations.The UPGMA dendrogram analysis separated the tested populations into two genetically differentiated subgroups:the first subgroup included two populations(Jincheng and Changzhi)from southeast Shanxi,the second subgroup made up of four populations from central and northern Shanxi.This result was in agreement with structure-based analysis.Collectively,we inferred that the populations of S.reilianum in Shanxi province may come from two ancestral subpopulations,and the genetic components of most strains are single.Our findings provide a theoretical basis for the integrated control of corn head smut.

关 键 词：玉米丝黑穗病菌 SSR标记 遗传多样性 群体结构 

分 类 号：S432.44[农业科学—植物病理学]