釋放赤眼卵蜂（Trichogramma chilonis）防治稻縱捲葉蟲及影響該蜂活動因子之研究

Abstract

本試驗於民國72年在水稻移植後60天在稻田試行釋放稻縱捲葉蟲（Cnaphalocrocis medinalis）之卵寄生赤眼卵蜂（Trichogramma chilonis），放蜂率19,000隻／公畝及9,000隻／公畝，兩處理區在放蜂後均提高寄生率，但彼此差異不顯著。另在移植後85天進行第二次放蜂，結果兩處理區與對照區之寄生率亦無顯著差異。 又進行T. chilonis之爬行、飛行受溫度、濕度、風速、不同寄主植物之影響等研究，結果發現該蜂之爬行速率隨溫度之升高而增加。溫度若低於25℃時其活動速率開始降低。相對濕度大於92.0% 或小於33.0% 時其爬行速率顯著降低。風速小於3.6m / sec時則爬行速率差異不顯著。T. chilonis在6種寄主植物上之活動以玉米葉背、甘蔗及柑橘葉片上之爬行速率最高，水稻、玉米葉表、甘藍葉次之，大豆葉最低。 Percent parasitism of host eggs increased by first release of Trichogramma chilonis at 60 days after rice transplanting at the rates of 19,000 and 9,000 T. chilonis per are. The results showed that it was not significantly different between these two releases. The second release was conducted at 85 days after rice transplanting, the percent parasitism of host eggs was not significantly different between treatments and control. Travel rate of T. chilonis increased by raising temperature. Its activity decrease when temperature below 25°C. We also found that travel rate was significantly decreased when relative humidity was above 92.0% or below 33.0%. However, travel rate was not significantly different when the wind velocity lower than 3.6m/sec. T. chilonis have higher searching rate on the undersurface of corn leaves, leaves of sugarcane and citrus, but do lower on the leaves of rice, cabbage, soybean, and upsurface of corn leaves.