不同化学药剂对烟草赤星病的防治效果

Control Effects of Different Chemical Agents against Brown Spot

[目的]筛选对烟草赤星病防治效果较好的化学药剂用于农药的交替轮换使用,为减轻烟草赤星病菌的抗药性提供参考。[方法]采用田间小区试验,比较40%菌核净可湿性粉剂、80%代森锰锌可湿性粉剂、40%灰核宁可湿性粉剂、3%多抗霉素可湿性粉剂、70%甲基托布津可湿性粉剂、75%扑海因可湿性粉剂、45%咪鲜胺水乳剂7种化学药剂对烟草赤星病的防治效果。[结果]同一化学药剂的不同浓度对烟草赤星病的防治效果不同,第2次施药后10 d调查,代森锰锌以600倍稀释液的防治效果最好,其相对防效为60.7%,菌核净、灰核宁和多抗霉素均以500倍稀释液的防治效果最好,其相对防效分别为69.8%、66.9%和64.1%,甲基托布津和扑海因均以800倍稀释液的防治效果最好,其相对防效分别为65.8%和63.6%,咪鲜胺以400倍稀释液的防治效果最好,其相对防效为61.9%。不同药剂在其最佳处理浓度下对烟草赤星病的防治效果不同,其中以40%菌核净可湿性粉剂500倍稀释液对烟草赤星病的防治效果最好,第1、2次施药后10 d的防治效果分别为63.8%和69.8%,其次为70%甲基托布津可湿性粉剂800倍稀释液,第1、2次施药后10 d的防治效果分别为62.1%和65.8%,均显著高于其他药剂。[结论]40%菌核净可湿性粉剂和70%甲基托布津可湿性粉剂的防治效果明显,可用于生产中推广使用。

[ Objective ] Some efficient chemical agents against brown spot were screened out for alternating rotation using to provide reference to reduce resistance of tobacco brown spot pathogen. [ Method ] Control effects of 40% Sclerotium net wettable powder, 80% Mancozeb wettable powder, 40% ash nuclear rather wet sex powder, 3% of Ampbotericin wettable powder, 70% Thiophanate methyl wettable powder, 75% Iprodi- one wettable powder, 45% Prochloraz water emulsion against brown spot were studied by using field plot test. [ Result] The same chemical agent of different concentration of tobacco red star disease prevention and cure effect was different. In 10 days after the second applying agent, 500 times diluents of the Sclerotium net had the best control effect, and its control effect was 69.8% ; 600 times diluents of the Mancozeb had the best con- trol effect, and its relative control effect was 60.7% ; 500 times diluents of the grey nuclear better had the best control effect, and its relative control effect was 66.9% ; 500 times diluents of the Amphot.ericin had the best treatment effect, and iis relative control effect was 64.1% ; 800 times diluents of the Thiophanate methyl had the best control effect, and its relative control effect was 65.8% ; 800 times diluents of the Iprodione had the best control effect, and its relative control effect was 63.6% ; 400 times diluents of the Prochloraz had the best control effect, and its rel- ative control effect was 61.9%. Different agents in their own best treatment concentration of tobacco red star disease prevention and cure effect were different, in all processing, among them 500 times diluents of the 40% Sclerotium net wettable powder had the best control effect, with con- trol effect of 63.8% in 10 days after the first applying agent and control effect of 69.8% in 10 days after the second applying agent, and 800 times diluents of the 70% Thiophanate methyl wettable powder had the best control effect, with control effect of 62.1% in 10 days after the first applying agent and control effect of 65.8% in 10 days after the second applying agent, furthermore these two agents of relative control effect were significantly higher than other agent processing. [ Conclusion] The 40% Sclerotium net wettable powder and 70% Thiophanate methyl wettable powder have obvious control effect, so they can be used in the production of the popularization and use.