Nachappa Punya, Braman S K, Guillebeau L P, All J N
Department of Entomology, University of Georgia, Athens, GA 30602, USA.
J Econ Entomol. 2006 Oct;99(5):1583-9. doi: 10.1603/0022-0493-99.5.1583.
The functional response of the tiger beetle Megacephala carolina carolina L. (Coleoptera: Carabidae) was determined on adult twolined spittlebug, Prosapia bicincta (Say) (Hemiptera: Cercopidae), and fourth instars of fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), in single-prey and two-prey systems. In the laboratory, M. carolina carolina demonstrated a type II functional response for P. bicincta and S. frugiperda in both single- and two-prey systems. Search efficiency of M. carolina declined for both prey as the initial number of prey increased. Of the total prey consumed, M. carolina carolina killed significantly more S. frugiperda than P. bicincta in the single-prey system (8.0 and 4.5, respectively) and the two-prey system (5.0 and 2.0, respectively). Estimates of attack coefficient, a, were not significantly different for P. bicincta and S. frugiperda in the single-prey (0.07 and 0.02) and two-prey systems (0.04 and 0.06), respectively. The handling time, T(h), was significantly greater for P. bicincta (5.02 and 10.64 h) than for S. frugiperda (2.66 and 4.41 h) in single- and two-prey systems, respectively. Estimations of attack coefficient and handling time in the single-prey system were used to predict prey preference of M. carolina carolina. No strong prey switching response was observed. M. carolina carolina showed no preference for either prey. However, in the presence of S. frugiperda, the functional response of the predator for P. bicincta was reduced. M. carolina carolina is a potential predator of one or more turfgrass pests and should be considered in conservation efforts.
在单猎物和双猎物系统中，测定了卡罗莱纳大头虎甲（Megacephala carolina carolina L.，鞘翅目：步甲科）对双线沫蝉（Prosapia bicincta (Say)，半翅目：沫蝉科）成虫以及草地贪夜蛾（Spodoptera frugiperda (J.E. Smith)，鳞翅目：夜蛾科）四龄幼虫的功能反应。在实验室中，卡罗莱纳大头虎甲在单猎物和双猎物系统中对双线沫蝉和草地贪夜蛾均表现出II型功能反应。随着猎物初始数量的增加，卡罗莱纳大头虎甲对两种猎物的搜寻效率均下降。在单猎物系统（分别为8.0和4.5）和双猎物系统（分别为5.0和2.0）中，卡罗莱纳大头虎甲捕杀的草地贪夜蛾数量显著多于双线沫蝉。在单猎物系统（分别为0.07和0.）和双猎物系统（分别为0.04和0.06）中，对双线沫蝉和草地贪夜蛾的攻击系数估计值无显著差异。在单猎物和双猎物系统中，双线沫蝉的处理时间T(h)（分别为5.02和10.64小时）显著长于草地贪夜蛾（分别为2.66和4.41小时）。利用单猎物系统中的攻击系数和处理时间估计值来预测卡罗莱纳大头虎甲的猎物偏好。未观察到强烈的猎物转换反应。卡罗莱纳大头虎甲对两种猎物均无偏好。然而，在有草地贪夜蛾存在的情况下，捕食者对双线沫蝉的功能反应降低。卡罗莱纳大头虎甲是一种或多种草坪害虫的潜在捕食者，在保护工作中应予以考虑。
