不同温度对食蚜瘿蚊生长发育和幼虫捕食能力的影响

Effects of temperature on the development and predation of Aphidoletes aphidimyza(Rondani) larvae

【目的】明确不同温度对食蚜瘿蚊Aphidoletesaphidimyza(Rondani)幼虫生长发育、捕食能力及控蚜效能的影响。【方法】在实验室不同温度条件下,测定了食蚜瘿蚊从卵到老熟幼虫的发育历期和日捕食量,并测定了食蚜瘿蚊3龄初幼虫的捕食功能反应。【结果】随着温度的升高,食蚜瘿蚊卵和幼虫发育速度加快,捕食天数减少,总捕食量增加,各温度间的总捕食量差异显著。温度为22-30℃时,食蚜瘿蚊幼虫在第3-4天开始捕食蚜虫,随后的1-2d内日捕食量达到高峰,随猎物密度增加,3龄初幼虫捕食量有明显的逐级上升趋势。每个温度下食蚜瘿蚊幼虫对玉米蚜Rhopalosiphum maidis (Fitch)的捕食功能反应均符合HollingⅡ型方程,18-30℃最大捕食量分别为30.9、33.0、35.2、48.9头,食蚜瘿蚊幼虫瞬时攻击率26℃时最高为0.99,单头猎物处理时间在30℃时最短为0.02 d。食蚜瘿蚊的控蚜能力30℃时最强,当温度降低时,其控蚜能力相应减弱。【结论】较高的温度有利于食蚜瘿蚊幼虫的发育、捕食和对蚜虫的控制。

[Objectives] To explore the effects of temperature on the development, predation and biological control potential of Aphidoletes aphidimyza larvae.[Methods] The development, predation and predatory functional response were investigated under different temperatures.[Results] Developmental duration and predation decreased with increasing temperature from 18 ℃ to 30 ℃. At 22-30 ℃, aphids were first eaten in the 3 rd to 4 th day of egg production, followed by a peak of predation over the following 1-2 days. There was a significant increase in predation by 3 rd instar larvae with increased density at 22-30 ℃. At 18-30 ℃, the functional response of A. aphidimyza 3 rd instar larvae to R. maidis approximated a HollingⅡ model, daily maximum numbers of aphids preyed on by A. aphidimyza were 30.9, 33.0, 35.2 and 48.9, respectively.The highest instantaneous attack rate was 0.985 at 26 ℃, the shortest handling time was 0.02 d at 30 ℃, and control ability was strongest at 30 ℃.[Conclusion] Higher temperatures speed the development and improve the predatory capacity of A.aphidimyza.