Effect of different vegetable oils on the toxicity of cypermethrin in mixed formulations to the adults of Mylabris pustulata Thunb.

Studies were carried out to enhance the susceptibility level of M. pustulata Thunb. to cypennethrin in cambination with certain non-toxic vegetable oils, viz., karanj oil, neem oil, sesame oil and citronella oil along with standard synergist (piperonyl butoxide). Neem oil and citronella oil proved synergistic at both the ratios, i.e., 1: 1 and 1: 5; whereas sesame oil and wen known synergist PBO produced only additive effect at 1: 1 ratio. Karanj oil exhibited antagonism with cypermethrin at both the ratios. Obviously, cypermethrin + neem oil and cypennethrin + citronella oil provide the desired combination to overcome resistance in M. pustulata and significantly greater control than cypermethrin alone.