Effect of synergists Piperonyl butoxide, S’S’S’ tribute phosphorotrithioate and Triphenyl phosphate on resistant Bapatla strain of Tribolium castaneum Herbst
Naga Satyasri CH, Madhumathi T and Sairam Kumar DV
A laboratory experiment was carried out in the Department of Entomology to know the toxic effect of synergists on commonly used insecticides against Tribolium castaneum Herbst. The synergists such as PBO, DEF and TPP showed synergistic factors of 89.58, 238.80 and 153.57 at LC50 and 3.17, 6.0 and 503 at LC99.9 level respectively with malathion. The corresponding synergistic values for dichlorvos were 58.8, 35.33 and 15.14 at LC50 and 2.50, 2.13 and 0.32 at LC99.9 level, while these values were 56.42, 25.48 and 21.03 at LC50 level and 1.80, 0.6 and 0.49 at LC99.9 level for deltamethrin. The levels of resistance to malathion, dichlorvos and deltamethrin are brought down significantly with all the three synergists viz., PBO, DEF and TPP.