Department of Entomology and Acarology - Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil.
Entomology Department, University of Nebraska-Lincoln, Lincoln, NE, USA.
Pest Manag Sci. 2017 Nov;73(11):2244-2251. doi: 10.1002/ps.4595. Epub 2017 Jun 9.
Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hübner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food.
In intraguild interactions, S. frugiperda had greater survival (55-100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea.
Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry.
草地贪夜蛾（Spodoptera frugiperda）（鳞翅目：夜蛾科）是玉米的主要害虫之一，与夜蛾科害虫斜纹夜蛾（Helicoverpa zea）和棉铃虫（Helicoverpa armigera）同属一个取食群体，最近在南北美洲均有报道。本研究通过测定幼虫在非 Bt 玉米花丝和玉米穗上的互作情景中的存活率，评估了这些物种在实验室和田间条件下的种内相互作用。此外，利用视频跟踪系统评估了有或没有食物时幼虫在互作情景中的行为参数。
在种内相互作用中，当幼虫处于相同龄期或比竞争者大（第四龄相对于第二龄）时，草地贪夜蛾与斜纹夜蛾竞争时的存活率更高（55-100%）。在食物中，草地贪夜蛾幼虫的取食频率和时间受到相互作用的负面影响。与斜纹夜蛾相比，草地贪夜蛾幼虫移动的距离更短（小于 183.03cm）。
总体而言，草地贪夜蛾在与斜纹夜蛾竞争时具有优势。本研究提供了有关夜蛾行为和种内互作中幼虫存活率的重要信息，这可能会影响害虫的流行和种群动态，从而影响这些物种在玉米上的综合虫害管理和昆虫抗性管理。© 2017 英国化学学会。
