戊唑醇等四种杀菌剂防治花生冠腐病应用研究

采用菌丝生长速率法和孢子萌发法分别测定了4种杀菌剂对花生冠腐病(Peanut crown rot)致病菌黑曲霉(Aspergillus niger v.Tiegh.)的毒力。结果表明:4种药剂中咪鲜胺、戊唑醇对菌丝生长表现明显的抑制作用,其EC50分别为0.01、0.03mg/L,其次为醚菌酯、多.福(1∶1),EC50依次为0.13、0.24mg/L;另外,咪鲜胺、戊唑醇、醚菌酯、多.福对花生冠腐病孢子萌发均有明显的抑制作用,其EC50依次为0.01、0.02、0.09和0.11mg/L。温室盆栽试验中,播种期、团棵期接菌后对照发病率分别为97.50%、92.50%,且四种药剂处理后的病情指数明显低于对照,防效接近或在90%以上。田间防治试验结果表明,戊唑醇在播种期、团棵期处理防效均最高,分别为80.63%和77.48%,同时,从对花生产量影响来看,团棵期比播种期施药后增产率高,其中团棵期施用戊唑醇增产率最高为7.01%。因此,建议选用戊唑醇于花生团棵期灌墩施用防治冠腐病,以减轻其危害,提高花生产量。

The Applied Research of 4 Fungicides against Peanut Crown Rot

Toxicity of 4 fungicides to Aspergillus niger v. Tiegh that causing peanut crown rot was tested with the mycelium growth rate and spore germination methods. Both prochloraz and tebu- conazole showed strong toxicity against A. niger, and EC50 for mycelial growth was 0.01mg/L and 0. 03mg/L respectively. The EC50 of kresoxim-methyl and carbendazim＋thiram （1 ： 1） was 0.13mg/L and 0.24mg/L respectively. The effects on spore germination test showed that prochloraz, tebucon- azole, kresoxim-methyl and carbendazim＋ thiram had obvious inhibitory effects, and their EC50 was 0. 01mg/L, 0. 02mg/L, 0. 09mg/L and 0. 11mg/L respectively. The pot experiment4n greenhouse showed that the disease incidence was 97.50% and 92.50% respectively after inoculation in sowing time and rosette stage. The disease index was decreased significantly after treated with 4 fungicides, and the control effects were close or above 90%. The field experiment indicated that tebuconazole had the highest effect both in sowing time and rosette stage. The production rate was higher treated with 4 fungicides in rosette stage than in sowing time, and the yield of peanut was increased by 7.01% when using tebuconazole. In the rosette stage, tebuconazole can be chosen as the ideal pesticide against crown rot in peanut field.