Evaluation of fumigant toxicity of the essential oil of Citrus reticulata fruit peels and synergistic effect of diethyl maleate and acetone in the control of the adult cowpea weevils, Callosobruchus maculatus F. (Col.: Bruchidae)

Many plants have compounds with insecticidal properties. In recent years، certain compounds of plants with insecticidal properties have been considered as alternatives to chemical pesticides for pest control. In this study، the respiratory toxicity of tangerine essential oil was evaluated on the mortality rate of the adults of Callosobruchus maculatus F. (Col.: Bruchidae). The experiment was carried out at 27 ± 1 0C and 60 ± 5% relative humidity in darkness. All experiments were based on CRD. LC50 and LC95 values for adults were 88. 93 and 205. 54 microliter per liter of air، respectively indicating the toxicity of tangerine essential oils on the studied pest. The insecticidal effect of essential oils of tangerine and acetone and synergistic effect of diethyl maleate were also assessed against cowpea beetle. LC50 values for the insects exposed to essential oil alone and along with synergist were 88. 93، and 54. 54 microliter per liter of air، respectively based on probit analysis. To determine the synergistic effect of acetone on tangerine lethality، LC25 values of both of them were calculated، combined and evaluated on insect host. Results showed that acetone and diethyl maleate had synergistic effects on tangerine essential oil.