摘要
不同病圃同一套寄主的田间表现及其穗颈瘟分离菌株的遗传宗谱和致病性分析试验结果证明,不同生态稻区稻瘟病菌的小种分布类型不同,对品种的致病性也存在差异。将已经过RFLJ和PCR技术进行DNA指纹分析,并划分为不同遗传宗谱的稻瘟病菌株进行致病性测定。结果表明,菌株的致病性与其遗传宗谱类型、生理小种类型、寄主及采集地点存在密切的关系:(1)同一遗传宗谱、分离自相同寄主、鉴定出来的生理小种类型又较接近的菌株,其致病性相似率最高;(2)同一遗传宗谱的菌株,如果所鉴定的生理小种类型较接近,且来自同一采集地点,即使是不同寄主上分离的菌株,其致病性相似率也较高;(3)不同遗传宗谱、不同寄主上分离的菌株,致病性差异较大。目前,在选择应用于品种或资源抗性鉴定的菌株时,必须将鉴别寄主测定的小种致病型与菌株的宗谱类型、寄主及采集地点结合起来,才能保证选出的菌株可靠、代表性强。
The distribution of physiological races of rice blast was tested on the same set of hosts in different nurseries as well as the genetic lineage and the pathogenicity of the blast isolates. The results indicate that the distribution of races was different and so was the pathogenicity to rice culti-vars. There was close relationship between the pathogenicity of the blast isolates and their genetic lineage, type of races, host and the site of collection presented by the result of the pathogenicity test of the isolates that were divided into different types by RFLP and PCR finger printing. (1) The isolates from the same genetic lineage and isolated from the same host with close related race types showed highest similarity in pathogenicity. (2) Isolates fell into the same genetic lineage and collected from the same site presented higher rate of similarity even if they were not from the same host. (3) The pathogenicity of isolates tested as different lineage and collected from different hosts differed greatly. When selecting rice blast isolates for identification of cultivar of germplasm resistance, the pathogenicity identified by differential hosts must be combined with the DNA finger printing of isolates, host and collecting site so that the reliability and the representative of the isolates could be ensured.
出处
《植物保护学报》
CAS
CSCD
北大核心
2000年第4期289-294,共6页
Journal of Plant Protection
基金
广东省自然科学基金项目(970674)
