RESUMO

We characterized the dynamics of mortality factors affecting immature developmental stages of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Multiple decrement life tables for egg and early larval stages of S. frugiperda in maize (Zea mays L.) fields were developed with and without augmentative releases of Telenomus remus Nixon (Hymenoptera: Platygastridae) from 2009 to 2011. Total egg mortality ranged from 73 to 81% and the greatest egg mortality was due to inviability, dislodgement, and predation. Parasitoids did not cause significant mortality in egg or early larval stages and the releases of T. remus did not increase egg mortality. Greater than 95% of early larvae died from predation, drowning, and dislodgment by rainfall. Total mortality due to these factors was largely irreplaceable. Results indicate that a greater effect in reducing generational survival may be achieved by adding mortality to the early larval stage of S. frugiperda.

Assuntos

Agentes de Controle Biológico , Spodoptera/crescimento & desenvolvimento , Vespas , Zea mays , Animais , Brasil , Larva , Comportamento Predatório

RESUMO

This work reports the first record of omnivory behavior of Diabrotica speciosa (Coleoptera, Chrysomelidae), Leptoglossus zonatus (Hemiptera, Coreidae), Monocrepidius aff. posticus and Monocrepidius fuscofasciatus (Coleoptera, Elateridae) on fall armyworm Spodoptera frugiperda (Lepidoptera, Noctuidae) egg masses in maize fields. Macrophotography was used to record the activity of these insects on fall armyworm sentinel egg masses during 2009 and 2010 maize growing seasons. The presence of omnivorous insects changes the species population dynamics within the ecosystem. Therefore, the implications of these interactions should be understood and taken into consideration for integrated pest management enhancement.