己唑醇与丁香菌酯对水稻纹枯病菌增效作用及其生化特性的影响

Synergistic and Effects of Biochemical Characteristics of Hexaconazole and Coumoxystrobin against Rhizoctonia solani

[目的]为探明己唑醇与丁香菌酯组合对水稻纹枯病菌协同作用及其初步机制。[方法]采用菌丝生长速率法测定了其对水稻纹枯病菌的联合生物活性,且采用离体叶片法测定了增效组合对水稻纹枯病的防效效果;并分析增效组合初步增效机制。[结果]己唑醇与丁香菌酯以有效成分1:4时,EC50值为0.105 mg/L,联合作用系数为155.90,增效明显,对离体叶片上纹枯病的相对防效达到80.79%。增效组合处理菌丝后,细胞膜通透性增加,可溶性蛋白含量降低,SOD酶活性升高,POD酶活性降低。[结论]增效组合(1:4)能够对水稻纹枯病菌生化特性产生显著的影响,从而表现对水稻纹枯病菌的增效作用。

[Aims] This study aims to confirm synergism and mechanism of the mixture of hexaconazole with coumoxystrobin to Rhizoctonia solani. [Methods] The joint-toxicity of mixtures of the two fungicides to R. solani was examined through the mycelial growth rate method, the relative control efficacy of synergism combination against R.solani by detached leaf bioassay of rice, and the antifungal mechanism of synergism combination were analyzed.[Results] The results showed that the mixtures of hexaconazole and coumoxystrobin at the ratio of 1:4 revealed significant synergistic effect with EC50 values of 0.105 mg/L with CTC value of 155.90, the control effect of the synergism combination by detached leaf method gave 80.79% relative control efficacy. After the hypha were treated with synergism combination, the cell membrane permeability increased, the soluble protein content decreased, SOD activity increased, and POD activity decreased. [Conclus ions ] The synergic combination(1:4) can significantly affect the biochemical characteristics of R. solani, thus showing the synergic effect on R. solani.