Bioactivity of the Cymbopogon citratus (Poaceae) essential oil and its terpenoid constituents on the predatory bug, Podisus nigrispinus (Heteroptera: Pentatomidae).

摘要: Podisus nigrispinus Dallas (Heteroptera: Pentatomidae), released in biological control programs, is a predator of Lepidopteran and Coleopteran species. Lemongrass essential oil its constituents can be toxic to this natural enemy. The major lemongrass are neral (31.5%), citral (26.1%), geranyl acetate (2.27%). Six concentrations were applied the thorax P. nymphs adults. walking respiratory behavior third-instar nymphs, treated with at LD50 LD90 doses, analyzed video respirometer. toxicity increased from first- fifth-instar nymphs. respiration rates (μL de CO2 h−1/insect) differed. Nymphs exposed on surfaces presented irritability or repelled. adults tolerant constituents, citral. altered activity fact that they irritated repelled by suggest caution regard use integrated pest management incorporating predator, order avoid diminishing efficiency against pests.