水稻主要抗瘟基因对我国菌株的抗性分析和利用评价

为了明确主要抗瘟基因的抗性现状和利用价值，１９９５－１９９６年采用徕自浙江，四川，湖北，广东等７个省（市）的１５５个稻瘟病菌菌株，测定了日本１３个已知基因粳稻品种的抗性表现。结果表明，１３个抗瘟基因对我国菌株的抗性均不强，菌株毒力频率均在２０％以上。但对我国各稻区的菌株而言多数稻区仍有１－３个基因的抗性保持较高的水平，浙江稻区Ｐｉ－ｚ＾ｔ基因仍有很好的抗性，能抗９５．７％的浙江菌株，四川稻区Ｐｉ－

ANALYSIS AND UTILIZATION OF MAJOR GENE RESISTANCE TO BLAST IN CHINA

155 isolated of rice blast fungus, Pyricularia grisea, were collected from seven provinces or cities in China for evaluating the resistance of 13v Japonica varieties with known genes during 1995 - 1996. Results showed that the virulent frequency (VF) of 155 isolated to 13 varieties were 20. 8% - 99. 3%. There were 1 - 3 genes that was resistant to most isolates at different rice areas. VF of gene Pi-z', carried by c. v. Toride No. 1, was only 4. 3% in Zhejiang Province. VF of K3(Pk-kh), Fukunishiki (Pi-z), and Kusabue (Pi-k) were below 10% in Sichuan Province and so were those of Toride No. 1 (Pi-z') and Pi-4 (Pi-ta2) in Yunnan Province. The prospects of applying major gene resistance in China were discussed.