金银花白粉病防治药剂筛选

Screening of fungicides to control powdery mildew on honeysuckle

[目的]筛选防治金银花白粉病(Erysiphe lonicerae)的有效杀菌剂,指导田间科学用药。[方法]采用盆栽法测定氟硅唑、苯醚甲环唑、吡唑醚菌酯等5种药剂室内生物活性测定,常规喷雾法测定药剂对金银花安全性及田间药效试验。[结果]氟硅唑对金银花白粉病菌的生物活性最高,EC50值为0.9043 mg/L,其次为苯醚甲环唑和吡唑醚菌酯的生物活性,EC_(50)值分别为1.1320、1.5761 mg/L。氟硅唑、苯醚甲环唑和吡唑醚菌酯对金银花叶片、枝条生长、鲜质量均无不良影响,对金银花安全、无药害发生。田间药效试验结果表明:400 g/L氟硅唑乳油80.0 mg/kg、25%吡唑醚菌酯悬浮剂250 mg/kg、10%苯醚甲环唑水分散粒剂166.6 mg/kg第2次施药后的田间防效分别为83.60%、81.54%、79.82%,均能有效防控金银花白粉病。[结论]400 g/L氟硅唑乳油、10%苯醚甲环唑水分散粒剂、25%吡唑醚菌酯悬浮剂对金银花白粉病有很好的防治效果,病害发生前或初发病时使用,间隔7~10 d左右再施药1次,整个生长季最多用药2次,为避免抗药性的产生,建议与其他类型杀菌剂交替使用。

[Aims]The aims of this study is to screen out effective fungicides for controlling Erysiphe lonicerae,and guide their scientific use in the field.[Methods]The pot test method was used for the bioassay of 5 fungicides including flusilazole,difenoconazole,pyraclostrobin and other two fungicides.The spray method was used to determine their safety and field efficacy.[Results]Flusilazole had the highest activity against E.lonicerae,with an EC_(50) value of 0.9043 mg/L,followed by difenoconazole and pyraclostrobin,with EC50 values of 1.1320 and 1.5761 mg/L,respectively.Flusilazole,difenoconazole and pyraclostrobin had no negative influence on the growth of leaves and branches and weight of honeysuckle,indicating that they were safe and harmless to honeysuckle.Field efficacy trials indicated that flusilazole 400 g/L EC at 80.0 mg/kg,pyraclostrobin 25%SC at 250 mg/kg and difenoconazole 10%WG at 166.6 mg/kg were all effective in controlling honeysuckle powdery mildew,with control efficacy of 83.60%,81.54%and 79.82%after the second application.[Conclusions]Flusilazole 400 g/L EC,difenoconazole 10%WG and pyraclostrobin 25%SC are effective to control the powdery mildew on honeysuckle.It should be used before or at the onset of the disease,and used again with an interval of 7-10 d.Throughout the entire growing season,it can be applyed no more than two times.To avoid the development of resistance,it is recommended to use it alternately with other types of fungicides.