Abstract: Race specific resistance and field resistance of 30 monogenic rice lines resistant to rice blast,derived from different resources were evaluated.The resistance spectrum(RS) of the tested monogenic lines ranged from 0.6% to 89.6%.Most of the monogenic lines showed narrow RS and high susceptibility in the blast zone,but the lines with Pikh and Pi1(t) showed good and stable blast resistance in field with the RSs of 89.6% and 82.2%,respectively.According to the cluster analysis of specific resistance to 163 blast isolates collected from indica rice in Guangdong Province,China,the 30 monogenic lines were divided into 15 groups,and based on the principal component analysis,9 kinds of race-specific resistance were identified.Pik,Piz5,Pi9,Pish could be used as candidate resistance genes for future rice breeding since their specific resistance differed from those of the key parents in Guangdong.Pyramiding of Pikh[or Pi1(t)],Pi9(or Piz5) and Pish(or Pita2) will be an effective measure to obtain broad spectrum blast resistance in local rice breeding program.The strategy for studying rice blast resistance genes and its application was discussed.

Key words: rice, race specific resistance, field resistance, Magnaporthe grisea, resistance gene

摘要： 对来自不同抗源的30个抗稻瘟病单基因系进行了小种专化抗性及田间抗性的分析和评价。30个单基因系对163个广东省稻瘟病菌株的抗谱介于0.6%~89.6%，大多数单基因系对测试的病菌表现出较窄的抗谱，在病区表现为高度感病，但含有Pikh 和 Pi1(t)的单基因系表现出广谱抗性，抗谱分别为89.6% 和 82.2%，在病区表现出较好的田间抗性。基于抗性基因与163个稻瘟病菌的抗感互作聚类分析，将30个单基因系的小种专化抗性划分为15个类型。主成分因子分析结果表明，其中9个类型的小种专化抗性表现出较大差异，可解释总变异的81.3%。含有Pik、Piz5、Pi9、Pish的单基因系在小种专化抗性上有别于广东省骨干亲本，这些基因在今后抗性育种中可重点引入。Pikh\[或 Pi1（t）\]、Pi9（或 Piz5）及Pish（或 Pita2）的基因聚合有利于提高广东省水稻品种对该地区稻瘟病菌的抗谱。并就稻瘟病抗性基因的研究及利用策略进行了讨论。

关键词: 水稻, 小种专化抗性, 田间抗性, 稻瘟病菌, 抗性基因