Indoxacarb effects on non-target predator, Podisus distinctus (Hemiptera: Pentatomidae).

Abstract

Forestry pest management includes biological and chemical methods of pest control. Using insecticides and natural enemies can be compatible in forest pest management programs. The compatibility of the predatory stink bug Podisus distinctus with the insecticide indoxacarb, used in forestry, needs to be evaluated in Brazil. This study investigated the mortality, survival, respiration, preference, prey consumption, and locomotor activity of P. distinctus adults exposed to indoxacarb. In concentration-mortality bioassays, the lethality of indoxacarb (LC50 = 2.62g L-1 and LC90 = 6.11g L-1) was confirmed in P. distinctus adults. The survival rate was 100% in predator insects not exposed to indoxacarb, declining to 40.7% in predator insects exposed to 2.62g L-1 and 0.1% in predators treated with 6.11g L-1. Indoxacarb reduced the respiration of P. distinctus from 18.45 to 14.41 µL CO2 h-1 at 2.62g L-1 for up to 3h after insecticide exposure, inhibiting food consumption and displaying hyperexcitation. The harmful effects of indoxacarb to the natural enemy suggest that it should be better assessed for use with P. distinctus for pest management in forestry.