广东烟叶主要真菌病害无公害化学防治药剂筛选试验

Screening and test of non-polluted chemicals for controlling main tobacco fungal diseases in Guangdong

烟草黑胫病和赤星病已成为广东烟叶生产的重要真菌病害,开展其无公害化学药剂筛选和应用研究势在必行。以烟草黑胫病菌和赤星病菌为研究对象,室内毒力测定结果表明:烯酰吗啉和氟吡菌胺的对烟草黑胫病菌的毒力最高(EC50分别为0.56μg/m L和0.25μg/m L),苯酰菌胺对烟草黑胫病菌的毒力次之(EC50为1.14μg/m L);咪鲜胺对烟草赤星病菌的毒力最高(EC50为0.26μg/m L),75%肟菌·戊唑醇水分散粒剂对烟草赤星病菌的毒力较高(EC50为2.66μg/m L)。田间试验结果表明:处理后15 d,推荐药剂50%烯酰吗啉可湿性粉剂1 500倍和80%苯酰菌胺可溶性粉剂2 500倍轮换施用防治烟草黑胫病的效果为87.23%;推荐药剂45%咪鲜胺水乳剂2 000倍和75%肟菌·戊唑醇水分散粒剂2 500倍轮换施用对烟草赤星病的效果为82.53%;均显著高于对照药剂的防治效果。研究结果为烟叶真菌病害化学防控提供了技术指导,促进了烟叶绿色安全生产,保证了烟叶产量和品质。

The tobacco black shank and brown spot have been become the important fungal diseases in Guangdong, so it is necessary to study the screening and application of non-polluted chemicals. In this paper, the research objects were tobacco black shank and brown spot. The results of laboratory bioassay indicated that the toxicities of dimethomorph and fluopicolide against Phytophtora parasitica var. nicotianae were the highest, and the values of median effective concentration （EC50）were 0.56 μ g/mL and 0.25 μ g/mL respectively; the toxicity of Phenylamide was lower than that of dimethomorph and fluopicolide, and the ECs0 was 1.14 μ g/mL. The toxicity of prochloraz amines against Alternaria alternata was the highest of all, and the ECs0 was 0.26 μ g/mL; the toxicity of 75% trifloxystrobin · tebtlconazole water dispersible granule （ WDG ） was lower than that of prochloraz amines,and the ECso was 2.66 μ g/mL. The results of flied experiments showed of. after a 15 d-treatment, the control effect of rotation application of 50% dimethomorph wettable powder （ WP ） 1 500 × and 80% Phenylamide WP 1 500 × against tobacco black shank was 87.23%; the control effect of rotation application of 45% prochloraz amines emulsion in water （ EW ） 2 000 × and 75% trifloxystrobin ~·tebuconazole WDG 2 500 × against tobacco brown spot was 82.53% ; the values of control effect of recommended agents were higher than that of contrast agents （ P 〈 0.05 ） . The research provided technical guidance for chemical control of tobacco fungal diseases, promoted the green safe production of tobacco, and ensured the yield and quality of tobacco.