Department of Entomology, Cornell University, Ithaca, NY 14853, USA.
J Econ Entomol. 2010 Aug;103(4):1149-58. doi: 10.1603/ec09384.
The larval feeding requirements and biology of the generalist predatory muscid hunter fly Coenosia attenuata Stein 1903 (Diptera: Muscidae) were investigated at 25 degrees C. Larval C. attenuata were fed second-, third, and fourth-instar (L2, L3, and L4) larvae of the fungus gnat Bradysia impatiens (Johannsen) (Diptera: Sciaridae) at variable rates to determine minimum and optimum numbers of these prey required for normal development. The proportion of C. attenuata larvae surviving to pupation differed significantly as a function of L2 and L3 prey numbers. When the number of prey/d was increased from 10 to 15 L2 and from 5 to 7 L3 per day, the respective percentages of pupation increased from 0 to 77% and from 0 to 48%. In contrast, all numbers of L4 prey (1-7 prey per d) supported pupation, and the pupation rate did not vary with prey number. At the highest prey numbers tested, mortalities of C. attenuata larvae fed L2, L3, and L4 fungus gnat larvae were 7, 30, and 75%, respectively. The higher mortality of larvae fed L4 prey was clearly the result of lethal wounds inflicted by the fungus gnat larvae in defensive strikes against the predators. At prey numbers supporting maximum rates of adult emergence, larval development required 12-14 d, and duration of the pupal stage was approximately 10 d. C. attenuata larvae killed large numbers of prey during their development (means of up to 232 L2, 144 L3, or 87 L4 fungus gnats), and larvae provided with marginally inadequate numbers of prey survived for long periods (mean 14-22 d, maximum 34 d) before succumbing to apparent starvation. These are favorable attributes with respect to use of C. attenuata as a biological control agent, suggesting a strong potential to substantially impact high-density pest populations and to survive in low-density pest populations.
在 25°C 下，研究了广食性捕食性蝇类猎蝇 Coenosia attenuata Stein 1903 的幼虫取食需求和生物学特性。幼虫 C. attenuata 以不同的速率喂食第二、三、四龄（L2、L3 和 L4）真菌蚋幼虫 Bradysia impatiens（Johannsen）（双翅目：摇蚊科），以确定正常发育所需的这些猎物的最小和最佳数量。幼虫 C. attenuata 存活到蛹化的比例随 L2 和 L3 猎物数量的变化而显著不同。当每天的猎物数量从 10 增加到 15 个 L2 和从 5 增加到 7 个 L3 时，相应的蛹化率分别从 0 增加到 77%和从 0 增加到 48%。相比之下，所有数量的 L4 猎物（每天 1-7 个猎物）都支持蛹化，并且蛹化率不随猎物数量而变化。在所测试的最高猎物数量下，喂食 L2、L3 和 L4 真菌蚋幼虫的 C. attenuata 幼虫死亡率分别为 7%、30%和 75%。喂食 L4 猎物的幼虫死亡率较高显然是由于真菌蚋幼虫在防御性攻击中对捕食者造成的致命伤口所致。在支持成虫最大出蜂率的猎物数量下，幼虫发育需要 12-14 天，蛹期持续约 10 天。C. attenuata 幼虫在发育过程中杀死了大量的猎物（高达 232 个 L2、144 个 L3 或 87 个 L4 真菌蚋），并且提供给幼虫数量不足的猎物在明显饥饿之前可以存活很长时间（平均 14-22 天，最长 34 天）。这些对于将 C. attenuata 用作生物防治剂来说是有利的属性，这表明它具有很大的潜力来显著影响高密度害虫种群，并在低密度害虫种群中存活。
