农地乐52．25％乳油防治甜菜夜蛾田间药效试验与示范

试验结果表明，农地乐 ５２．２５ＥＣ防治甜菜夜蛾速效性好于对照药剂抑太保和除尽，药后 １ｄ的防效，１０００、６６７倍液达 ８０％以上，５００倍液达 ９０％以上。药后 ７ｄ的防效，１０００、６６７倍液为 ９１．４％～９３．３％，与抑太保 １０％乳油 １０００倍液相当；５００倍液为 ９６．７％，与除尽相当。农地乐 ５２．２５ ＥＣ防治甜菜夜蛾的持效期为 ７～８天。农地乐对作物安全。示范面积２．１× １０３ｈｍ２，平均防 效达 ８５％以上。农地乐 ５２．２５ ＥＣ已成为冀东防治甜菜夜蛾的首选药剂。

Control Effect of Chlorpyrifos + beta - cypermethrin 52 .25EC against Spodoptera exigua Hubner

The field trial was conducted in 1999 on chlorpyrifos + befa - cypermethrin 52. 25EC against Spodoptera exigua. The result indicat- ed that chlorpyrifos + beta - permethrin showed a quicker control effect than chlorfluazuron and chlorfenapyr: the efficacies of chlorpyrifos + be- ta - permethrin were over 80% one day after treatment with 1000 and 667 times dilutions, over 90% with 500 times dilution. The efficiencies of chlorpyrifos + beta - cypermethrin 52.25EC 7 days after applying with 1000 and 667 times dilutions were similar to chlorfluazuron 10EC with 1000 times dilution, with 500 times dilution the efficiency was about the same to chlorfenapyr with 3333 times dilution. The efficacious duration of chlorpyrifos + beta - cypermethrin to control Spodoptera exigua was 7 - 8 days. Chlorpytifos + beta - cypermethrin was safe to the crop. Chlorpyrifos + beta - cypermethrin was used in 2000 for demonstration of controlling Spodoptera exigua on a large scale in east Hebei province. The wanted result was obtained, which was similar to the field trial.