烟草根黑腐病化学防治药剂及复配增效配方的筛选

Selection of chemical control agents and compound synergistic formulas of tobacco black root rot

目的:筛选防治烟草根黑腐病菌的有效单一药剂及其复配制剂。方法:采用菌丝生长速率法测定7种商品化杀菌剂对烟草根黑腐病菌的室内毒力活性,筛选出防效较好的单一杀菌剂;在此基础上,对防效较好的单一杀菌剂进行复配,并对复配药剂开展烟草根黑腐病菌的室内毒力测定试验。结果:室内杀菌剂毒力测定结果表明,咪鲜胺、甲基硫菌灵2种杀菌剂对烟草根黑腐病菌均具有较强的抑制作用;且咪鲜胺和甲基硫菌灵按1∶1复配时,对烟草根黑腐病菌毒力有明显的协同增效作用,EC_(50)为0.19 mg/L。结论:咪鲜胺和甲基硫菌灵单剂及其复配药剂均对烟草根黑腐病菌的菌丝生长具有抑制效果,该结果为后续烟草根黑腐病田间防效试验提供了理论依据。

Objective:Effective single fungicides and its compounded fungicides for preventing and controlling Thielaviopsis basicola were screened and obtained.Methods:Mycelial growth rate method was used to determine the indoor virulence activity of seven kinds of fungicides against the Thielaviopsis basicola t o screen out fungicides with good control efficacy.Then the single fungicide with good control effect was selected and compounded to determine the indoor virulence activity against Thielaviopsis basicola.Result:Prochloraz and Thiophanate methyl had a strong inhibitory effect on Thielaviopsis basicola.When prochloraz and thiophanate methyl were compounded at a ratio of 1∶1,it had a synergistic effect with an EC_(50) value of 0.19 mg/L.Conclusion:The selected single fungicides prochloraz,thiophanate methyl and its compounded fungicides had inhibitory effects on mycelial growth of Thielaviopsis basicola.This study could provide a theoretical basis for the research of tobacco black root rot,and also lay a foundation for the next field control experiment.