中国农业科学 ›› 2018, Vol. 51 ›› Issue (1): 82-95.doi: 10.3864/j.issn.0578-1752.2018.01.008

• 植物保护 • 上一篇    下一篇

禾谷镰孢复合种毒素化学型及遗传多样性分析

马红霞,孙华,郭宁,张海剑,石洁,常佳迎   

  1. 河北省农林科学院植物保护研究所/农业部华北北部作物有害生物综合治理重点实验室/河北省农业有害生物综合防治工程技术研究中心, 河北保定 071000
  • 收稿日期:2017-06-21 出版日期:2018-01-01 发布日期:2018-01-01
  • 通讯作者: 石洁,E-mail:shij99@163.com
  • 作者简介:马红霞,E-mail:mahongxia0792@163.com
  • 基金资助:
    国家现代农业产业技术体系(CARS-02)

Analysis of Toxigenic Chemotype and Genetic Diversity of the Fusarium graminearum Species Complex

MA HongXia, SUN Hua, GUO Ning, ZHANG HaiJian, SHI Jie, CHANG JiaYing   

  1. Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences/Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture/IPM Centre of Hebei Province, Baoding 071000, Hebei
  • Received:2017-06-21 Online:2018-01-01 Published:2018-01-01

摘要: 【目的】明确不同省(自治区)引起玉米穗腐病的禾谷镰孢复合种(Fusarium graminearum species complex,FGSC)的毒素化学型和它们之间的遗传差异以及亲缘关系。【方法】选用根据基因Tri13和Tri3序列设计的特异性引物分析来自11个省(自治区)的92株禾谷镰孢复合种菌株的毒素化学型;从100条哥伦比亚大学(UBC)开发的通用引物中筛选出13 条扩增条带丰富、重复性好、信号强、背景清晰的引物,利用筛选出的引物对供试菌株进行ISSR-PCR扩增,使用Popgen32软件计算多态性位点百分率、Shannon’s多样性指数、群体间的遗传距离和遗传相似性;依据Nei’s 遗传距离,利用NTsys2.10e软件进行UPGMA聚类分析,并构建供试菌株的聚类图。【结果】供试的92株禾谷镰孢复合种菌株的产毒素化学型有4种:DON、15-ADON、DON+15-ADON和NIV+15-ADON。其中产生DON和15-ADON的菌株分别为1株和20株;同时产生15-ADON和NIV的有1株;同时产生15-ADON和DON的有55株。筛选出的13条引物对所有供试菌株进行PCR扩增,共获得102条带,其中多态性条带101条,多态性比率为99.02%,平均每条引物产生条带为7.85条。在群体平均水平上,基因多样性指数(H)为0.3129,Shannon’s的信息指数(I)为0.4774,表明禾谷镰孢复合种存在较高的遗传多样性水平;不同地理种群间,各群体的遗传多样性水平具有一定差异,河北、山西、黑龙江和吉林种群遗传多样性最高,安徽和河南种群最低。地理种群间的基因分化系数(Gst)为0.2722,说明不同地理种群间存在一定的遗传变异,但大部分遗传变异(72.78%)发生在种群内。遗传分化系数估算的基因流值Nm=1.3372(>1),表明不同地理种群间存在一定的基因流动;遗传关系结果表明河北、山西、黑龙江、吉林、辽宁、内蒙古和甘肃菌株群体间亲缘关系较近,山东、江苏、河南和安徽菌株间亲缘关系较近,安徽和内蒙古菌株间的亲缘关系最远。聚类分析显示所有菌株相似系数为0.43—0.95。在相似系数为0.43时,所有菌株分成2大类群,Group 1包括4株北方春播区菌株(吉林、山西和河北张家口),不产生NIV和DON;Group 2由余下的88株菌株构成,产生的毒素类型主要为DON和15-ADON,其来源于北方春播区(山西、黑龙江、吉林、辽宁、甘肃和河北张家口、唐山)和黄淮海夏播区(河北石家庄、河南、山东、江苏和安徽),在相似系数为0.664时,各类群分成不同的亚群,亚群的结果与菌株来源有一定的相关性。聚类分析结果和毒素化学型分析显示,同一地理种群的菌株多数聚在一起,个别菌株分散到不同的分支上。【结论】北方春播区和黄淮海夏播区的禾谷镰孢复合种主要的毒素化学型为DON和15-ADON。引起玉米穗腐病的禾谷镰孢复合种菌株群体内存在丰富的遗传变异,不同地理种群间存在一定的基因交流,遗传多样性与地理来源有关。

关键词: 禾谷镰孢复合种, 毒素化学型, 遗传多样性, ISSR, 玉米穗腐病

Abstract: 【Objective】The objective of this study is to clarify the toxigenic chemotype and genetic diversity of Fusarium graminearum species complex (FGSC) causing maize ear rot from different provinces (autonomous region).【Method】The toxigenic chemotypes of 92 FGSC isolates collected from 11 provinces (autonomous region) were analyzed by using the specific primer designed based on Tri13 and Tri3 sequences. Thirteen primers with abundant bands, good repeatability, strong signal and clear background were screened from 100 universal primers developed by Columbia University (UBC) and used for ISSR-PCR amplification of these isolates. The Popgen32 software was used to calculate the percentage of polymorphic loci, Shannon’s diversity index, genetic distance and genetic similarity among populations. According to Nei’s genetic distance, UPGMA cluster analysis was carried out using NTsys2.10e software, and the dendrogram of different geographical populations was constructed. 【Result】 Four different toxigenic chemotypes including DON, 15-ADON, DON+15-ADON and NIV+15-ADON were detected among 92 FGSC isolates. One and 20 isolates represented the DON and 15-ADON chemotypes, respectively. One isolate produced both 15-ADON and NIV, and 55 isolates carried both 15-ADON and DON producing segments. The PCR amplification of all FGSC isolates was performed with 13 ISSR primers and a total of 102 fragments were obtained, of which 101 fragments displayed polymorphic and accounted for 99.02% in the total amplified fragments. The average number of fragments amplified per primer was 7.85. At population average level, the Nei’s gene diversity index (H) was 0.3129 and the Shannon’s information index (I) was 0.4774, which indicated that there was a high genetic diversity in FGSC isolates. The diversity existed among fungal populations from different geographic regions. Hebei, Shanxi, Heilongjiang and Jilin had the highest genetic diversity, while Anhui and Henan had the lowest genetic diversity. The genetic differentiation coefficient (Gst) of geographical populations was 0.2722, indicating that there were some genetic variations among different geographical populations, but most of the genetic variation (72.78%) occurred in the population. The Nm=1.3372 (>1) indicated that there was a certain gene flow among different geographical populations. The results of genetic relationship showed that the populations of Hebei, Shanxi, Heilongjiang, Jilin, Liaoning, Inner Mongolia and Gansu were relatively close, and the populations of Shandong, Jiangsu, Henan and Anhui also displayed a close relationship, whereas the population isolated from Anhui had the lowest similarity with population isolated from Inner Mongolia. Cluster analysis showed that the similarity coefficient of all isolates was 0.43-0.95. All the isolates were divided into two groups with the similarity coefficient of 0.43. Group 1 included 4 isolates of northern spring sowing region (Jilin, Shanxi and Zhangjiakou, Hebei), which did not produce NIV and DON. Group 2 consisted of the remaining 88 isolates which originated from northern spring sowing region (Shanxi, Heilongjiang, Jilin, Liaoning, Gansu and Hebei (Zhangjiakou and Tangshan)) and Huang-Huai-Hai summer sowing region (Henan, Shandong, Jiangsu, Anhui and Shijiazhuang, Hebei), and the toxins produced by these isolates were mainly DON and 15-ADON. When the similarity coefficient was 0.664, each group was divided into different subgroups, and the results of subgroups were related to the source of the isolates.【Conclusion】The main toxigenic chemotypes of FGSC from northern spring sowing region and Huang-Huai-Hai summer sowing region are DON and 15-ADON. There are abundant genetic variations in the populations of FGSC causing maize ear rot. There are certain gene exchanges among different geographical populations. The genetic diversity was related to the geographical origin.

Key words: Fusarium graminearum species complex (FGSC), toxigenic chemotype, genetic diversity, ISSR, maize ear rot