瘤野螟(Cnaphalocrocis medinalis Guen'ee, Rice leaf folder)是水稻生育期間重要的害蟲。本試驗目的在瞭解瘤野螟在中臺灣的族群消長情形,評估最適當的防治時機及針對良質米品種進行抗性檢定。由誘蟲燈的資料顯示,瘤野螟一年有8個世代,族群高峰期分別出現於6月下旬、8月中旬、9月中旬及10月中下旬。當成蛾發生盛期,每網掃可捕獲1隻成蛾後7天進行第一次施藥,隔14天再施藥一次的處理方式,應是最佳的防治適期。防治藥劑則以2.8%賽洛寧乳劑2,000倍對瘤野螟的防治效果最好,防治率高達95%。此外,正確的施藥可明顯增加水稻千粒重及稔實率。調查9個主要的水稻栽培品種對瘤野螟的抗性,以臺稉8號具有較佳的抗性。
Rice leaf folder, Cnaphalocrocis medinalis Guen'ee, is a seriously insect pest in the cultivated periods of rice. In this study, the population dynamics, the optimal timing for insecticides applied and the resistant rice varieties of rice leaf folder in central Taiwan were examined. Data shown from light trap indicates there are eight generations of rice leaf folders in each year. The major population peaks occurred in late-June, mid-August, mid-September and mid- and late-October, respectively. When the first application of insecticides was carried on the seventh days after maximum moth peak occurred, in which more than one moth were caught per sweeping net, and the second application of insecticides was processed 14 days later, these turned out to be better control timing for rice leaf folder to recommend farmers. In such conditions, 2.8% Cyhalothrin EC had the best control efficiency and the control percentage reached up to 95%. Furthermore, the 1,000-grain weight and the seed setting rate were increased significantly as the optimal timing was applied. Nine quality rice varieties were tested for resistance to rice leaf folders and Tai-Keng No. 8 owns better resistant characteristics than others.