啶酰菌胺与唑胺菌酯混配对灰葡萄孢毒力的增效作用

为明确啶酰菌胺与唑胺菌酯对灰葡萄孢Botrytis cinerea毒力的增效作用,采用菌丝生长速率法测定了啶酰菌胺与唑胺菌酯不同配比混合物对灰葡萄孢菌株DZ3(对多菌灵、乙霉威和嘧霉胺高抗)的毒力,以Wadley公式评价了其协同作用。选取最佳增效组合,采用黄瓜子叶喷雾法测定了其对其他5个菌株的毒力及田间防效。通过测定菌株DZ3分生孢子悬浮液中的溶氧量、电导率和菌丝中丙二醛的含量,研究最佳增效组合的增效机制。结果表明:啶酰菌胺与唑胺菌酯不同质量比(9∶1、7∶1、5∶1、3∶1、1∶1、1∶3、1∶5、1∶7和1∶9)的混合物均对菌株DZ3表现为毒力增效作用,其中质量比为1∶3的组合增效最明显,增效系数达4.76,且对另外5个供试菌株的联合毒力也表现出增效;在使用剂量为有效成分200~300 g/hm2时,质量比为1∶3的组合对番茄灰霉病的防治效果为78.05%~93.96%,同时其对菌株DZ3的呼吸抑制作用与单剂啶酰菌胺相当,但对细胞膜通透性和菌丝膜脂质过氧化的影响均显著高于各单剂。本研究结果表明,啶酰菌胺与唑胺菌酯以质量比1∶3进行混配,可用于番茄灰霉病的防治。

Synergistic activity of mixtures of boscalid and pyrametostrobin against Botrytis cinerea

In order to clarify the synergistic action of the mixtures of boscalid and pyrametostrobin against Botrytis cinerea, the inhibitory activity of the mixtures at different mixing ratios to isolate DZ3 was determined by mycelial growth rate method, and the synergistic radio was calculated according to the Wadley formula. The inhibitory activity of the best mixture to the other five isolates of B. cinerea was determined by inoculating fungicide-sprayed cucumber cotyledons with conidial suspension, and the control efficacy against tomato grey mould was determined in the field. The synergistic mechanism of the best synergistic combination was studied by detecting the content of dissolved oxygen, conductivity of the conidial suspension of isolate DZ3, and the content of malondialdehyde in the hyphae of isolate DZ3. The results showed that the mixtures of boscalid and pyrametostrobin (9 :1, 7 :1, 5 :1, 3 :1, 1 :1, 1 :3, 1 :5, 1 :7 and 1 :9,m/m) exhibited synergistic activity against the mycelial growth of isolate DZ3, and the 1 :3 mixture exhibited the most significant synergistic effects, with synergistic ratio up to 4.76. The 1 :3 mixture also showed synergistic inhibition to the other five isolates of B.cinerea. The control efficacy of the mixture (1 :3, m/m) against tomato gray mould in the field was 78.05%-93.96% at 200-300 g a.i./hm², and the inhibitory activity of the mixture (1 :3, m/m) on the respiration of isolate DZ3 was similar to that of boscalid, but the impact on membrane permeability and mycelium membrane lipid peroxidation was more significant than that of individual boscalid and pyrametostrobin. The results of present study suggested that the mixture of boscalid and pyrametostrobin (1 :3, m/m) could be used in controling of tomato gray mould.