筛选能有效防治甘蓝菌核病、马铃薯茎基腐病和黄瓜灰霉病 3种蔬菜真菌性病害的适宜杀菌剂，为蔬菜病害防治提供低毒高效的杀菌剂选择，缓解常用的多菌灵、菌核净、嘧霉胺等杀菌剂的抗药性发展。采用菌丝生长速率法测定了 25%吡唑醚菌酯悬浮剂、 50%戊唑醇悬浮剂、 240 g/L噻呋酰胺悬浮剂 3种化学合成杀菌剂和 0.2%白藜芦醇可溶液剂、 0.5%小檗碱水剂以及 1%蛇床子素水乳剂 3种植物源杀菌剂对核盘菌、立枯丝核菌、灰葡萄孢 3种蔬菜病原真菌的离体抑菌活性，并对甘蓝、马铃薯、黄瓜 3种蔬菜的盆栽防效作了初步评价。结果表明， 50%戊唑醇悬浮剂对灰葡萄孢和核盘菌抑菌效果最佳，其次是 25%吡唑醚菌酯悬浮剂； 240 g/L噻呋酰胺悬浮剂对立枯丝核菌的抑菌效果最佳，盆栽防效均在 77%以上，其次是 25%吡唑醚菌酯悬浮剂； 0.2%白藜芦醇可溶液剂、 0.5%小檗碱水剂、 1%蛇床子素水乳剂对核盘菌、立枯丝核菌的盆栽防效显著低于以上 3种化学合成杀菌剂。综上可知， 25%吡唑醚菌酯悬浮剂和 50%戊唑醇悬浮剂具有较好的广谱性，均可防治核盘菌、立枯丝核菌、灰葡萄孢 3种病原真菌； 240 g/L噻呋酰胺悬浮剂适合防治立枯丝核菌引起的病害；其余 3种植物源杀菌剂较低剂量不适合单独使用。

To screen suitable fungicides for effectively controlling fungal diseases in 3 vegetable crops (cabbage, potato, cu.cumber), provide low-toxicity and high-efficiency fungicide alternatives for vegetable disease management, and to mitigate the devel.opment of pathogen resistance to commonly used fungicides such as carbendazim, dimethachlon, and pyrimethanil, the in vitro antifun. gal activities of 3 chemically synthesized fungicides, namely 25% pyraclostrobin suspension concentrate (SC), 50% tebuconazole SC,240 g/L thifluzamide SC, as well as 3 plant-derived fungicides, namely 0.2% resveratrol soluble concentrate (SL), 0.5% berberineaqueous solution (AS), and 1% osthole emulsion in water (EW), against 3 vegetable pathogenic fungi (Sclerotinia sclerotiorum, Rhizocto. nia solani, and Botrytis cinerea) were determined using the mycelial growth rate method, and their pot control efficacies on the 3 vegeta.bles (cabbage, potato and cucumber) were preliminarily evaluated. Results showed 50% tebuconazole SC exhibited the best antifungalactivity against B. cinerea and S. sclerotiorum, followed by 25% pyraclostrobin SC. The 240 g/L thifluzamide SC showed the best anti. fungal activity against R. solani, and its control efficacy in pot experiments was above 77%, followed by 25% pyraclostrobin SC. Thepot control efficacy of 0.2% resveratrol SL, 0.5% berberine AS, and 1% osthole EW against S. sclerotiorum and R. solani were signifi.cantly lower than those of the above 3 chemically synthesized fungicides. In summary, 25% pyraclostrobin suspension concentrate and50% tebuconazole suspension concentrate showed good broad-spectrum activity and could both be used to control the 3 pathogenicfungi, S. sclerotiorum, R. solani, and B. cinerea. The 240 g/L thifluzamide suspension concentrate is suitable for controlling diseases caused by R. solani. The other 3 plant-derived fungicides at lower dosages are not suitable for separate application.

S436.3