Toxicity and behavioral effect of indoxacarb, Voliam Targo and profenofos on Habrobracon hebetor

Habrobracon hebetor is an important ectoparasitoid of several lepidopteran pests. The efficiency of parasitoids would be affected by insecticides applications. Integrating the application of biological control agents and insecticides for pest management requires knowledge about impact and selectivity of the insecticides on biological control agents. In this study, the lethal and sublethal effects of indoxacarb, Voliam Targo and profenofos were evaluated on different life stages and some behavioral responses of the parasitoid. Field recommended rate of Voliam Targo and profenofos caused 100 % mortality on adult female wasps. Based on bioassay tests, the LC50 values of indoxacarb, Voliam Targo and profenofos on adult stage were 172.5, 4.4 and 2.9 mg a.i./L, respectively. The result of bioassay experiments on adult stage showed that profenofos had higher toxicity against adult stage compared to indoxacarb and Voliam Targo. Field recommended rate of indoxacarb and Voliam Targo had low toxicity on immature stages of the parasitoid. The effect of LC30 of the tested insecticides on functional response as an important behavioral factor of parasitoids was also studied. The functional response of the parasitoid revealed a type II functional response in control and all of insecticides treatments. This study showed that the control and profenofos treatment had the shortest and longest handling time, respectively. The highest and lowest maximum attack rate was observed in profenofos and control treatments with 0.992 and 0.507 h, respectively. Evaluation of sublethal effects of indoxacarb, Voliam Targo and profenofos on orientation behavior of the wasp by olfactometer showed that the parasitoid preferred untreated host larvae compared with treated host larvae by tested insecticides. Results showed that profenofos had more negative effects on the parasitoid. Due to the high toxicity effect of Voliam Targo on adults, it seems that Indoxacarb would be a more suitable insecticide for using in integrated pest management programs.