创新杀菌剂对土传病原真菌的离体活性测定

The Bioactivity of Innovative Fungicides against Soil-borne Pathogenic Fungus in vitro

[目的]为了研究杀菌剂对尖孢镰刀菌、立枯丝核菌、瓜果腐霉菌的生物活性,采用菌丝生长速率法对多种杀菌剂及其混剂组合进行了离体抑菌活性测定。[结果]啶菌唑和苯醚甲环唑对黄瓜枯萎病菌的EC50值分别为0.3233、0.6604 mg/L;三环菌胺和甲霜灵对黄瓜猝倒病菌的EC50值分别为1.0282、2.5163 mg/L。啶菌唑与苯醚甲环唑、三环菌胺与甲霜灵两两配比组成混剂,不同混剂组合在部分配比中共毒系数大于120,表现出增效作用。[结论]毒力测定结果表明:啶菌唑、苯醚甲环唑、三环菌胺和甲霜灵分别对3种病菌表现出了很强的抑制作用;啶菌唑苯醚甲环唑(1∶5)、三环菌胺甲霜灵(1∶3和1∶5)分别对病菌表现出了明显的增效作用。

[Aims] For researching into the bioactivity of 10 fungicides against Fusarium oxysporum f.sp cucurnerinum, Rhizoctonia solani and Pythium aphanidermatum, the toxicity was tested by the inhibition zone rate methods. [Results] The results showed that the EC50 of pyrisoxazole（SYP-Z048） and difenoconazole to F. oxysporum f.sp cucumerinum were 0.3233 and 0.6604 rng/L respectively; while the ECs0of Sanhuanjunan（SYP- 2815） and metalaxy to P.. aphanidermatum were 1.0282 and 2.5163 mg/L respectively. The synergic toxicity tests to E oxysporum f.sp cucumerinum, R. solani and P. aphanidermatum showed that the CTC values of pyrisoxazole with difenoconazole, SYP-2815 with metalaxy were partly more than 120 and the mixed preparations had synergistic effect. [Conclusions] The toxicity test shows that pyrisoxazole, difenoconazole, SYP-2815 and metalaxy have the strong inhibition effect on the three pathogenic fungus, respectively. Pyrisoxazole with difenoconazole（1 ： 5）, SYP-2815 with metalaxy（1 ： 3 and 1 ： 5） have the obviously synergistic effect.