A Field Trial with a Single Application of Insecticides to Control the Rice Stem Borer, Chilo Suppressalis

Abstract

The authors have previously reported (1963) that poor kill of the larvae of the paddy borer, Schoenobius (Tryporyza) incertulas Walker became evident with some foliar sprays applied by a conventional knapsack sprayer beyond certain stage after transplanting when growth of the plants was so dense preventing the sprays from hitting the straws in which the larvae were feeding. In this trial, an investigation was made to determine whether or not significant control of the rice stem borer, Chilo suppressalis Walker which similarly feeds in the straw as the paddy borer, could be obtained with some compounds applied only once soon after transplanting before growth of paddy reached undesirable conditions for foliar treatment. 水稻移植二個月後行莖葉噴藥方法對三化螟幼蟲無大防治效果之試驗報告曾提出於本刊（1963年3月），因此設想在移植後一個月間應用前項噴藥法行一次用藥或許能有防治效果上之意義。本工作即基於該概念使用數種藥劑對二化螟進行試驗，其結果Parathion，EFN，Dimecron及Cidial等對其幼蟲具有充分之殺蟲力，但爾後調查其白穗發生數及收量，各處理區間未獲得有意義之差異。然由於本項試驗僅以小試驗區進行，對照及藥效較差之試驗區留存之螟蟲似能繁殖而移至他區為害，因此大面積之稻田照本試驗之方法行一次施藥或可收到相當之防治效果。