| dc.description.abstract | 本省產溫氏捕植蟎（A mblyseius womersleyi Schicha ）雌成蟎捕食二點葉蟎( Tetranychus urticae Koch ）之捕食率及產卵率與食餌密度成正比。溫氏捕植蟎在長方形面積為5 × 15 cm2的載台較其他面積載台具較高的食餌利用效率。每載台上每天餵食二點葉蟎卵及幼蟎（0.019或0.0059）之捕植蟎密度比每天餵食二點葉蟎若蟎及成蟎（0.019或0.0059）多；每日供餌量愈多，捕植蟎密度愈高，但捕植蟎對單位食餌之利用率則較低。每日固定餵食0.019葉蟎卵及幼蟎所獲之捕植蟎族群密度最高，且維持此高密度時間最長，為大量飼育溫氏捕植蟎時之最適供餌量。田間及網室內釋放溫氏捕植蟎或捕植及殺菌劑施藥時機均顯著有效抑制二點葉蟎密度，且低於未釋放區。生物防治及綜合防治區之捕植蟎密度及出現頻度較高。田間釋放捕植蟎可有效防治二點葉蟎達12 週或全季。於草莓定植3.5個月後（一月中旬之二期花果生產期）的自然防治區（未釋放捕植蟎及未施藥區），雖因溫氏捕植蟎的遷入且快速建立高密度捕植蟎族群，但已失去防治葉蟎的適期。網室內溫氏捕植蟎可於2-4 週內迅速抑制及有效防治葉蟎族群，之後因短期內食餌急速消耗殆盡，致捕植蟎族群滅絕，因此未能對後期（6-8週）侵入的葉蟎族群產生防治效果。捕植蟎釋放可配合選擇性殺蟲劑及殺菌劑施用，除有效防治二點葉蟎外，亦防治蟲害及減少病害之發生。釋放溫氏捕植蟎或配合化學藥劑均顯示該捕植蟎防治二點葉蟎之效果，顯然溫氏捕植蟎與選擇性殺蟲劑及殺菌劑具相容性，並可減少殺蟎劑之施用。總之，利用溫氏捕植蟎防治二點葉蟎有其實用價值。
Reproduction rates and daily predation rates of Amblyseius womersleyi (AW) feeding on Tetranychus urticae (TSM) were positively correlated with TSM density. Rate of daily prey utilization of AW was the highest on 5 x 15 cm2 among all tested sizes and shapes of artificial arenas. The higher density was obtained from arena of AW feeding on 0.01 g or 0.005 g per day of prey eggs and larvae than feeding on nymphs and adults. The predatory mites, feeding on 0.01 g or 0.005 g of a TSM diet of eggs and larvae, other than nymphs and larvae, produced a higher density on the arena. The higher the amount of daily prey was offered, the higher the AW density was, but the lower the rate of prey utilization was. Feeding daily on 0.01 g of TSM eggs and larvae, AW produced the highest density, which could be sustained for a longer duration on the arena; therefore, a better measurement of the amount of daily prey offer was determined.
In the field and saran house tests for AW releases, with or without integrating fungicides or insecticides, we found a promising result of the measures, evaluated from a low population density. The densities and frequencies of AW in the released plots were higher than those without AW-release throughout the strawberry harvest season; the AW release kept TSM population in check at low density. In the saran house, AW quickly suppressed the TSM to low density on the strawberry plants. However, AW tend to emigrate or were missing from the house, control of re-invaded TSM population later was made unlikely. The re-invaded TSM, after 6-8 weeks of the first release of AW, would not be controlled by AW, and thus caused serious damage.
The releases of AW are compatible with selected insecticide and/or fungicide; such integrated measures are effective in controlling TSM in strawberry systems and show a satisfying result with strawberry productivity. They also significantly reduce the amount and frequency of pesticide applications. In conclusion, we have proved that AW is a valuable biological control agent. | en_US |
