8种杀菌剂对甘蔗黑穗病菌的室内毒力测定

Bioactivities of eight fungicides against Sporisorium scitaminea

【目的】研究8种杀菌剂对甘蔗黑穗病菌的室内毒力,为甘蔗黑穗病药剂防治提供科学依据。【方法】采用冬孢子萌发抑制法、担孢子增殖抑制法及菌落生长速率法测定8种杀菌剂对甘蔗黑穗病菌的生物活性。【结果】嘧菌酯、苯醚甲环唑·嘧菌酯、噻呋酰胺、吡唑醚菌酯、吡唑醚菌酯·啶酰菌胺、啶酰菌胺、苯醚甲环唑对甘蔗黑穗病菌冬孢子萌发具有很好的生物活性,EC50分别为0.0117、0.0234、0.0636、0.1238、0.1441、13.7620和25.9300μg/mL,而丙环唑的活性较低,EC50为155.5000μg/mL。啶酰菌胺对甘蔗黑穗病菌担孢子增殖没有抑制作用,除嘧菌酯对"+"、"-"两种担孢子增殖的EC50分别为4.3250和5.3040μg/mL外,其余药剂的EC50均小于1.0000μg/mL。对甘蔗黑穗病菌菌丝生长抑制作用较好的药剂依次为丙环唑、苯醚甲环唑、噻呋酰胺、苯醚甲环唑·嘧菌酯、吡唑醚菌酯、吡唑醚菌酯·啶酰菌胺、啶酰菌胺,EC50分别为0.0145、0.0643、0.1291、0.1689、0.2535、0.6767和4.8610μg/mL,嘧菌酯对菌丝生长的抑制作用稍差,EC50为94.5000μg/mL。【结论】供试8种杀菌剂对甘蔗黑穗病菌不同生长时期均具有不同的生物活性,可进一步开展这些杀菌剂的田间药效防治试验。

[Objective]The bioactivities of 8 fungicides to Sporisorium scitaminea were tested in order to provide references for controlling and treating smut disease of sugarcane. [Method]Bioactivities of 8 fungicides against S. scitaminea were tested by observing teliospores germination, sporidia multiplication and mycelial growth of the fungi. [Result]The results showed that azoxystrobin, difenoconazoleoazoxystrobin, thifluzamide, pyraclostrobin, pyraclostrobinoboscalid, boscalid and difenoeonazole showed strong fungistatic actions against teliospores germination and the EC50 value was 0.0117, 0.0234, 0.0636, 0.1238, 0.1441, 13.7620 and 25.9300 μg/mL, respectively. But the bioactivity of propiconazole was low, with the EC50 value of 155.5000 μg/mL. Bosealid didn＇t inhibit sporidia multiplication. The EC50 values of azoxystrobin to the multiplication of ＂＋＂ and ＂-＂ sporidia were 4.3250 and 5.3040 μg/mL, respectively, and the EC50 values of the rest 6 fungicides were lower than 1.0000 μg/mL The fungicides with strong inhibiting function on Sponsorium seitaminea mycelial growth were propiconazole, difenoconazole, thifluzamide, difenoconazoleoazoxystrobin, pyraclostrobin, pyraclostrobin · boscalid and boscalid with the EC50 value of 0.0145, 0.0643, 0.1291, 0.1689, 0.2535, 0.6767 and 4.8610 μg/mL, respectively, while that of azoxystrobin was 94.5000μg/mL. [Conclusion]The tested 8 fungicides showed different fungistatic actions against the different phases of Sporisorium scitaminea, and their field effect should be further tested.