辽宁省稻瘟病菌对稻瘟灵的敏感性监测

Sensitivity detection of Pyricularia gresea to isoprothiolane in Liaoning Province

利用菌丝生长速率法,测定了自辽宁省主产稻区2009-2010年分离的87株稻瘟病菌对稻瘟灵的敏感性。结果表明,稻瘟灵的抑制中浓度EC50值为0.35～7.01μg/mL,敏感性差异达20倍;且2009年稻瘟病菌对稻瘟灵的敏感性高于2010年。根据野生敏感型病原群体对药剂敏感性呈正态分布的原理,辽宁省稻瘟病菌对稻瘟灵的敏感性基线定为(1.77±0.80)μg/mL,辽宁省主要稻区均有抗稻瘟灵菌株出现,除2010年在铁岭稻产区监测到1株中抗菌株外,大部分稻瘟病菌株都表现为低抗水平。稻瘟病菌不同生理小种群对稻瘟灵的敏感性无明显差别。

The mycelium growth rate method was used to test the sensitivity of 87strains of Pyricularia grisea to isoprothiolane from different distracts in Liaoning Province from 2009 to 2010. The results showed that the EC50 of the strains to isoprothiolane ranged from 0.35 - 7.01 μg/mL with a difference of more than 20 times. The sensitivity of strains isolated in 2009 to isoprothiolane was higher than that in 2010. According to gaussian distri- bution theory of wildly sensitive strains from field, the sensitive base-line of Pyricularia gresea isolates to iso- prothiolane was （ 1.77±0.80）μg/mL in Liaoning. Except one moderately resistant isolate existed in rice pro-ducing areas of Tieling, most of the isolates were low resistant to isoprothiolane. The sensitivity of strains be- longing to different physiologic race groups to isoprothiolane had no significant difference.