利用CARAH模型评价药剂组合对马铃薯晚疫病的防效

Evaluation of fungicide control effect on potato late blight under CARAH Model

为防治马铃薯晚疫病,设置了4种药剂组合喷施处理,在马铃薯生长前期使用保护性药剂,后期使用治疗性药剂,利用CARAH模型比较各药剂组合的防效。结果表明:在病害流行期,各药剂组合应用后的防病增产效果显著,末次施药后6 d对叶部晚疫病的防效达98%以上,较清水对照产量增幅在170%以上,商品薯率也高出17百分点以上。其中,以氰霜唑/氟菌·霜霉威组合的综合表现最好,末次施药后21 d相应处理区病害指数为9.57,折合产量为79342.07 kg/hm^(2),较对照增产279.21%,商品薯率94.74%,病薯率1.20%。综合分析发现,氰霜唑的预防效果优于代森锰锌,氟菌·霜霉威的保护治疗效果明显优于氟吗啉。研究结果可为马铃薯晚疫病防治药剂的科学选择与使用提供参考依据。

We used the CARAH forecasting system to predict the occurrence of potato late blight to guide the fungicide application.Plant protective agents were used in the early stage of late blight and therapeutic agents were applied in the late stage.The results showed that the effect of four different fungicide combinations on disease control and yield increase was significant during the disease epidemic period.The control effect on leaf late blight was more than 98%six days after the last application,which was over 170%higher than that of the water control,and the commercial potato rate also increased by more than 17 percentage points.Among them,the combination of cyanofamid and fluopicolide+propamocarb-hydrochloride showed the best comprehensive performance and the disease index of the corresponding treatment was only 9.57 after 21 days of the last application,and the average yield was 79342.07 kg/hm^(2),which was279.21%higher than that of the control.The rate of commercial potato and diseased tuber was 94.74%and 1.20%,respectively.The contrast test of different fungicides revealed that the preventive efficacy of cyanofamid was better than that of mancozeb,and the protective effect of fluopicolide+propamocarb-hydrochloride was significantly better than that of flumorph.Our results provide further insights into the selection and use of chemicals for controlling late blight.