Interactive effects of temperature and CO2 on efficacy of insecticides against Spodoptera litura Fab. in a global warming context

Influence of two dimensions of climate change i.e., elevated temperature ( e Temp) and elevated CO 2 ( e CO 2 ) on toxicity of insecticides against Spodoptera litura Fab. on peanut using CO 2 Temperature Gradient Chambers (CTGC) facility was investigated. The insecticides viz. , diamides (flubendiamide), avermectins (emamectin benzoate), organophosphates (quinalphos), spinosyns (spinosad) and synthetic pyrethroids (deltamethrin) were tested for their efficacy and persistence toxicity (PT) at e Temp and e CO 2 . The twelve set conditions comprising of reference (28 ± 0.5 °C; 380 ppm), eTemp (29, 30, 31, 32, 34 ± 0.5 o C with 380 ppm CO 2 ), e CO 2 (28 ± 0.5 o C; 550 ppm) and eTemp+ e CO 2 (29, 30, 31, 32, 34 ± 0.5 o c with 550 ppm CO 2 ) were maintained in CTGC. Interactive effects of e CO 2 and e Temp caused the higher LC 50 values of spinosad and deltamethrin with negative temperature coefficients and showed the ‘reduction of toxicity’. Lower LC 50 values and positive temperature coefficients for flubendiamide (6.67), emamectin benzoate (7.38) and quinalphos (3.04) were recorded, indicating the ‘higher toxicity’ at interactive e CO 2 and e Temp. The order in PT of insecticides was deltamethrin