Study on fumigative toxicity of five terpenoid compounds on the adults of Callosobruchus maculatus F. (Coleoptera: Bruchidae)

Searching for less hazardous compounds for human and invironment the fumigative toxicity of five terpenoid compounds including carvacrol, myrtol, menthol, camphen and a-pinene were investigated on Callosobruchus maculatus (F.) as one of the most important stored product pests. Experiment was carried out at 30 ± 2 ˚C and 60 ± 5% relative humidity (R.H.) under dark condition. Each compound were tested with six concentrations and four replications including control. According to the trial experiments the fumigant toxicity of the studied essential oils differed significantly , distinct concentrations of each compound used. The results showed that all compounds studied had significant mortality on the pest. Among them, Myrtol showed the highest fumigative toxicity on C. maculatus. The value of LC50 of Myrtol was 47.05µl/lair while LC50 of Carvacrol, Menthol, Camphen and α-pinene were respectively 51.53, 107.39, 61.35 and 57.41 µl/lair. It is concluded that the terpenoid compounds may be used in the pests of post-harvested products in stores.