José Pf Bentivenha1, Débora G Montezano2, Thomas E Hunt3, Edson Ll Baldin4, Julie A Peterson5, Vinícius S Victor4, Luiz Er Pannuti4, Ana M Vélez2, Silvana V Paula-Moraes6. 1. Department of Entomology and Acarology - Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil. 2. Entomology Department, University of Nebraska-Lincoln, Lincoln, NE, USA. 3. Haskell Agricultural Laboratory, University of Nebraska-Lincoln, Concord, NE, USA. 4. Department of Crop Protection, College of Agronomic Sciences, São Paulo State University, Botucatu, São Paulo, Brazil. 5. West Central Research and Extension Center, University of Nebraska-Lincoln, North Platte, NE, USA. 6. West Florida Research and Education Center, University of Florida, Jay, FL, USA.
Abstract
BACKGROUND: 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. RESULTS: 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. CONCLUSION: 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.
BACKGROUND: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. RESULTS: 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. CONCLUSION: 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.
Authors: Eduardo P Machado; Gerson L Dos S Rodrigues Junior; Junior C Somavilla; Fábio M Führ; Stefan L Zago; Luiz H Marques; Antonio C Santos; Timothy Nowatzki; Mark L Dahmer; Celso Omoto; Oderlei Bernardi Journal: Pest Manag Sci Date: 2020-06-29 Impact factor: 4.845