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利用全国统一的７个稻瘟病菌鉴别品种，把１９９７年采自全省２６个县市的９９个有效单孢分离菌划分为３５个生理小种。与１９８７～１９８９年的测定结果比较，出现了１６个新的生理小种，分别是ＺＡ１，ＺＡ２，ＺＡ９，ＺＡ１７，ＺＡ３３，ＺＡ３４，ＺＡ３８，ＺＡ４９，ＺＡ５４；ＺＢ５，ＺＢ１６，ＺＢ１０；ＺＣ８；ＺＤ５，ＺＤ６和ＺＦ２，且多为强致病力的ＺＡ群小种。过去的优势小种ＺＧ１已被ＺＡ１所取代。籼型种群小种出现频率在本次测定中为８７．８８％。结果表明，强致病力籼型小种的大量增加和广泛分布是导致许多水稻杂交组合感病化的主要原因。
The identification of seven species of Magnaporthe grisea in China was used to classify 99 effective single spore isolates collected from 26 counties and cities in the province in 1997 into 35 physiological races. Compared with the results from 1987 to 1989, 16 new physiological races emerged: ZA1, ZA2, ZA9, ZA17, ZA33, ZA34, ZA38, ZA49, ZA54; ZB5, ZB16, ZB10; ZC8; ZD6 and ZF2, and most of them are ZA group races with strong virulence. ZG1, the dominant race of the past, has been replaced by ZA1. The frequency of races of indica population was 87.88% in this test. The results showed that the large increase and extensive distribution of strong pathogenicity indica races is the main reason leading to many susceptible combinations of rice hybrids.