Nakano Ryo, Ihara Fumio, Mishiro Koji, Toyama Masatoshi, Toda Satoshi
Breeding and Pest Management Division, NARO Institute of Fruit Tree Science, 2-1 Fujimoto, Tsukuba, Ibaraki 305-8605, Japan; Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada.
Breeding and Pest Management Division, NARO Institute of Fruit Tree Science, 2-1 Fujimoto, Tsukuba, Ibaraki 305-8605, Japan.
J Insect Physiol. 2015 Dec;83:15-21. doi: 10.1016/j.jinsphys.2015.11.004. Epub 2015 Nov 5.
Bat-and-moth is a good model system for understanding predator-prey interactions resulting from interspecific coevolution. Night-flying insects have been under predation pressure from echolocating bats for 65Myr, pressuring vulnerable moths to evolve ultrasound detection and evasive maneuvers as counter tactics. Past studies of defensive behaviors against attacking bats have been biased toward noctuoid moth responses to short duration pulses of low-duty-cycle (LDC) bat calls. Depending on the region, however, moths have been exposed to predation pressure from high-duty-cycle (HDC) bats as well. Here, we reveal that long duration pulse of the sympatric HDC bat (e.g., greater horseshoe bat) is easily detected by the auditory nerve of Japanese crambid moths (yellow peach moth and Asian corn borer) and suppress both mate-finding flights of virgin males and host-finding flights of mated females. The hearing sensitivities for the duration of pulse stimuli significantly dropped non-linearly in both the two moth species as the pulse duration shortened. These hearing properties support the energy integrator model; however, the threshold reduction per doubling the duration has slightly larger than those of other moth species hitherto reported. And also, Asian corn borer showed a lower auditory sensitivity and a lower flight suppression to short duration pulse than yellow peach moth did. Therefore, flight disruption of moth might be more frequently achieved by the pulse structure of HDC calls. The combination of long pulses and inter-pulse intervals, which moths can readily continue detecting, will be useful for repelling moth pests.
蝙蝠与飞蛾是理解种间协同进化产生的捕食者 - 猎物相互作用的良好模型系统。夜间飞行的昆虫在6500万年里一直承受着来自使用回声定位的蝙蝠的捕食压力，迫使易受攻击的飞蛾进化出超声波探测和躲避策略作为应对手段。过去针对抵御攻击蝙蝠的防御行为的研究一直偏向于夜蛾科飞蛾对低占空比（LDC）蝙蝠叫声短脉冲的反应。然而，根据地区不同，飞蛾也受到了来自高占空比（HDC）蝙蝠的捕食压力。在这里，我们发现同域分布的HDC蝙蝠（如大马蹄蝠）的长脉冲很容易被日本禾螟蛾（桃蛀螟和亚洲玉米螟）的听觉神经检测到，并抑制未交配雄蛾的求偶飞行和已交配雌蛾的寄主寻找飞行。随着脉冲持续时间缩短，这两种蛾类对脉冲刺激持续时间的听觉敏感度均呈非线性显著下降。这些听觉特性支持能量积分模型；然而，脉冲持续时间每翻倍时阈值的降低幅度略大于迄今报道的其他蛾类。此外，亚洲玉米螟对短持续时间脉冲的听觉敏感度和飞行抑制程度均低于桃蛀螟。因此，HDC叫声的脉冲结构可能更频繁地干扰飞蛾的飞行。飞蛾能够轻松持续检测的长脉冲与脉冲间隔的组合，将有助于驱赶蛾类害虫。
