Valuation of Rosmarinus officinalis Essential Oils

The present work focuses on the study of the fumigant activity of essential oil of Rosemary leaves Rosmarinus officinalis (L., 1753) against the different stages and adults of two species of stored date moths the almond moth Ephestia cautella (Walker, 1863) and the Mediterranean moth Ephestia kuehniella (Zeller, 1879). The results show that the fumigant effect varies with the species, the stage of the insect, the concentration of the essential oil and the exposure time. The essential oil of R. officinalis was more toxic against E. cautella. In both insect species, the larval stages are more tolerant than the adult stage. Indeed, the respective LC50 values of the adult stage and L5 stage were 22.87 µl/l air and 146.22 µl/l air for Ephestia cautella against 4.24 µl/l air and 25073.82 µl/l air for Ephestia kuehniella. The TL 50 values of adult and L5 stage were 1.93 h and 17.01 h for Ephestia cautella against 4.93 h and 46.62 h for Ephestia kuehniella respectively for a concentration of 156.25 µl/l air.