芒果畸形病菌室内单剂及复配剂增效配比的筛选

Test of Toxicity of Fungicides and Screening for Synergistic Effect Ratio of Mixtures against Fusarium proliferatum Causing Mango Malformation

通过菌落生长速率法对我国芒果新病害——芒果畸形病病菌层出镰刀菌(Fusarium proliferatum)进行室内药剂筛选,以期为该病害的大田防治提供参考。结果表明:从9种单剂EC50和斜率综合来看,咪鲜胺锰盐(EC50为0.075μg/mL、斜率0.85)和多菌灵(EC50为0.3μg/mL、斜率3.69),应用潜力最大,其次是戊唑醇、丙环唑、氟硅唑、多.福.溴菌腈和甲基硫菌灵。29个复配组合中仅有3个配比组合表现出增效作用,其中丙环唑与多.福.溴菌腈以2∶3配比时增效最明显;其次是咪鲜胺锰盐与多.福.溴菌腈、多.福.溴菌腈与甲基硫菌灵分别以1∶4和2∶3的配比也表现出一定的增效作用。其余组合则表现相加或拮抗作用。

In order to control mango malformation which was a new disease of mango in China and identified to be caused by Fusarium proliferatum, toxicities of nine fungicides against F. proliferatum were tested using the mycelia growth rate method. Both the ECso value and slope rate of toxicity regression equation of each fungicide were determined. Prochloraz with EC~ value of 0.075 μg/mL and slope rate of 0.85, and carbendazim with ECso value of 0.3μg/mL and slope rate of 3.69, showed the highest application potential, followed by tebuconazole （ECso 0.36μg/mL）, propiconazole （ECso 0.84 μg/mL）, flusilazole （ECso 0.84 μg/mL）, carbendazim-thiram-bromothalonil （ECso 1.27 μg/mL） and thiophanate-methyl （EC~ 1.74 μg/mL）. Among 29 combinations of nine fungicides, three ratios were showed synergistic effect. The combination between propiconazole and carbendazim-thiram-bromothalonil at a 2：3 showed the largest synergistic effect. Combinations between prochloraz and carbendazim-tbiram- bromothalonil in the ratios 1：4, carbendazim-thiram-bromothalonil and thiophanate-methyl in the ratios 2：3 also showed synergistic effects. The rest combinations had additive or antagonistic effect.