中国农业科学 ›› 2007, Vol. 40 ›› Issue (4): 727-734 .

• 植物保护 • 上一篇    下一篇

云南致病疫霉交配型、甲霜灵敏感性、mtDNA单倍型及其群体演替研究

赵志坚,曹继芬,李灿辉 ,孙道旺,杨明英,王 军   

  1. 云南省农业科学院农业环境资源研究所,植物病理实验室
  • 收稿日期:2005-12-09 修回日期:1900-01-01 出版日期:2007-04-10 发布日期:2007-04-10

Population Genetics of Phytophthora infeseans:Ⅱ—Characteristics of Mating Type,Metalaxyl Sensitivity, Mitochondrial DNA Halpotype and Replacing of Populations in Yunnan During 2000 to 2003

  

  1. 云南省农业科学院农业环境资源研究所,植物病理实验室
  • Received:2005-12-09 Revised:1900-01-01 Online:2007-04-10 Published:2007-04-10

摘要: 【目的】对致病疫霉群体特征的认识,是控制晚疫病危害的必要前提。【方法】对云南32个马铃薯和番茄产区的致病疫霉群体的交配型、甲霜灵敏感性、mtDNA单倍型进行了研究。【结果】云南马铃薯致病疫霉群体主要由A1交配型组成,番茄致病疫霉全部为A1交配型。A2 交配型和自育型菌株总体发生频率较低,分别为3.4%和4.4%。自从2002年以后,致病疫霉的群体结构发生了明显的变化,没有检测到A2交配型或自育型菌株。致病疫霉对甲霜灵敏感性的离体测定显示马铃薯和番茄上均存在抗性、中抗和敏感菌株。甲霜灵抗性、中抗、敏感菌株分别占测定菌株的13.2% 、9.4%和 77.4%。分离自番茄的甲霜灵抗性菌株比例高于分离自马铃薯的菌株。Ⅰa 、Ⅱa 和 Ⅰb 三种mtDNA 单倍型被检测到,马铃薯致病疫霉有Ⅰa 和 Ⅱa 两种单倍型,全部为第二次全球迁移后出现的“新”群体。Ⅰa 单倍型在群体中的比例为96%,分布于所有马铃薯产区;番茄致病疫霉则为Ⅰa 和Ⅰb 两种单倍型,“新”、“旧”群体共存。【结论】马铃薯和番茄致病疫霉群体的遗传结构有明显差异;致病疫霉“新”、“旧”群体在云南已发生演替,马铃薯致病疫霉“新”群体已成功替代了“旧”群体;迁移和有限的有性生殖可能在云南致病疫霉群体的演替中担当了重要的作用。

关键词: 交交配型, 自育性, 甲霜灵敏感性, mtDNA单倍型, 晚疫病

Abstract: It is necessary for late blight disease control to characterize populations of phytophthora infestans. The characteristics of mating type, metalaxyl sensitivity and mtDNA haplotype of P.infestans isolates collected from 32 potato and tomato production regions in Yunnan were analyzed. The result showed that the A2 mating type and self-fertility isolates were rare on potato, average 3.4%and 4.4%respectively, which were detected at only 4 sites. Only were A1 mating type isolates collected from tomato detected and the composition of mating type had been changed dramatically in Yunnan since 2002. In vitro tests of sensitivity to the phenylamide fungicide metalaxyl showed that insensitive and sensitive isolates occurred on potato and tomato and the ratio of insensitive and sensitive ones was 22.6%and 77.4%respectively. The ratio of resistant isolates from tomato was higher than that from potato. Three mtDNA haplotypes Ⅰa,Ⅱa andⅠb were detected from P.infestans populations in Yunnan. Both Ⅰa and Ⅱa haplotypes of P.infestans collected from potato were the ‘new’ populations and the former predominated, dispersing in all potato production regions.Ⅰa and Ⅰb haplotypes from tomato isolates showed that the “old” and “new” populations of P.infestans coexisted. The result of mtDNA haplotypes revealed that replacement of P.infestans had occurred. Migration and rare sexual reproduction may play an important role on variation and replacement of P.infestans populations in Yunnan.

Key words: mating type, self-fertility, Metalaxyl sensitivity, mtDNA haplotype, late blight disease