植物病原真菌对甲基立枯磷的抗药性及风险研究

通过对人工获得的抗甲基立枯磷菌株的抗药水平、在培养基上的生长速度、致病力、对其它杀菌剂的敏感性测定以及对菌核的观察和用药条件等方面分析, 在实验室内进行了植物病原真菌对甲基立枯磷的抗药性风险研究。结果显示, 不同的病原菌具有不同的抗药性。抗甲基立枯磷的水稻纹枯病菌菌株对甲基立枯磷的抗药性较强、抗药性风险大; 小麦纹枯病菌和油菜菌核病菌抗药菌株抗药性较弱、风险小。抗甲基立枯磷的水稻纹枯病菌对菌核净具有高水平正交互抗性; 抗甲基立枯磷的小麦纹枯病菌对菌核净和扑海因有中等程度正交互抗性; 这两种真菌的抗药菌株对五氯硝基苯的正交互抗性弱, 对烯唑醇和异稻瘟净没有交互抗性。甲基立枯磷与二甲酰亚氨类和芳烃类杀菌剂具有相似的抑菌作用。

Resistance Risk of Plant Pathogenous Fungi to Tolclofos methyl

Resistance risk of the plant pathogenous fungi to tolclofos methyl was studied in lab. depending on testing resistant degree, growth ratio on PSA medium, infectivity to rice, sensitivity to other fungicides of the fungi, sclerotia examination, and analyzing condition of application of the tested fungicides; using resistant strains from lab.. Result showed that resistance risk to tolclofos methyl differed between different species of plant pathogenous fungi. High resistance and resistance risk to tolclofos methyl appeared in Rhizoctonia solani (rice sheath blight), but low in Rhizoctonia cerealis (wheat sheath blight ) and Sclerotinia sclerotiorum (rapeseeds sclertinia blight). Resistant strains of R. solani to tolclofos methyl showed relatively strong positive cross resistance to dimethachlon and high resistance risk. While that of R.cerealis to dimethachlon and iprodione is medium. Posifive cross resistance of both germ is low to quintozene. There was no any cross resistance between tolclofos methyl and diniconazole and IBP . Inhibiting activity of tolclofos methyl, dicarboximides and hydrocarbon aromatic is alike.