5种制剂及其防治组合对黄瓜霜霉病的防效评价

Control Effect of Five Kinds of Preparations and Combinations of Cucumber Downy Mildewand Its Evaluation

[目的]筛选防治黄瓜霜霉病的有效药剂,降低施药量和施药次数。[方法]利用叶盘漂浮法测定5种药剂对黄瓜霜霉病菌毒力,并对不同制剂组合田间防效评价。[结果]双炔酰菌胺对黄瓜霜霉病菌抑制效果最好,EC50值为0.482 5 mg/L;在春秋2季黄瓜田间防治中,250 g/L双炔酰菌胺悬浮剂与60 g/L甲壳胺水剂交替施药组合效果显著,药后14 d的防治效果分别为72.47%和73.27%。[结论]250 g/L双炔酰菌胺悬浮剂与60 g/L甲壳胺水剂交替施药组合与常规施药相比,施药量降低20%~30%,施药次数减少2次,且对黄瓜安全。

[Aims] The paper aims to screenout effective chemicals to control cucumber downy mildew, and to reduce pesticide application rate and time. [Methods] The fungitoxicity of five fungicides to Pseudoperono sporacubensis was tested by leaf disc floating method, and the effects of combinations on the control of cucumber downy mildew were evaluated in field. [Results] The mandipropamid had exhibited the highest inhibitory action to P. sporocuberuis, and the median inhibitory concentration was 0.482 5 mg/L; in spring and autumnfield control, the effect of mandipropamid 250 g/L SC and 60 g/L chitosan AS alternate spray combination was remarkable, with control effects 72.47 and 73.27% 14 days after spray. [Conclusions] Compared with chlorothalonil 75% WP conventional spray, application rate and time were reduced by 20-30% and 2, and it was safe.