四川省稻瘟病菌对稻瘟灵的抗药性研究

Study on Resistance of Pyricularia grisea to Isoprothiolane in Sichuan Province

采用生长速率法测定了2004-2007年分离自四川省16个地区（市、州）41个县（市）的208个有效稻瘟病菌单孢对稻瘟灵的抗药性。结果表明：全省最不敏感菌株EC50值（20.7794μg/mL）是最敏感菌株EC50值（0.8135μg/mL）的24.54倍。确定了四川省水稻稻瘟病菌对稻瘟灵的敏感基线为6.9749μg/mL。全省没有出现对稻瘟灵产生高抗药性和中抗药性菌株,大部稻瘟病菌株都表现为低抗水平（≤3）,有的地区低抗菌株出现频率为0。因此,只要加强田间抗药性监测,稻瘟灵在四川水稻生产上仍可作为防治稻瘟病的有效药剂使用。

The mycelium growth rate method was used to test the sensitivity to Isoprothiolane in 208 effective isolates of Pyricularia grisea which came from 41 counties of 16 cities in Sichuan province from 2004 to 2007. The results showed that the EC50 value of least sensitive isolate （20.7794 μg/mL） was 24.54 times more than the most sensitive isolates （0. 8135 μg/mL）. The sensitive base-line of P. grisea isolates to Isoprothiolane was 6.9749 μg/mL. No highly resistant and moderately resistant isolates existed in the major districts of the rice production in Sichuan. All of the isolates belonged to low resistant level （ ≤ 3 ） to lsoprethiolane. The fungicide of Isoprethiolane could be continued to apply in the Sichuan rice production.