Evaluation of the Insecticidal Activity of Punica granatum L. and Olea europaea L. against the Dry Bean Beetle , Acanthoscelides obtectus (Say) (Coleoptera:Bruchidae)

Abstract

A laboratory study was carried to determine the efficacy of Punica granatum Linn. and Olea europaea L. leaf powders against adults of the dry bean beetle, Acanthoscelides obtectus (Say) (Coleoptera:Bruchidae) under laboratory conditions . The death rate of A. obtectus increased gradually with increasing the concentration and period of exposure to powdered plant leaves. After 120 hours of exposure to the powdered plant leaves, P. granatum caused adult mortality 82.17%, while O. europaea caused adult death 68.14%. In case of P. granatum leaf powders, the LC50 value was 16.73 g / 30 g white kidney bean while LT50 recorded 69.01 hours at 25 g / 30 g white kidney bean. While the maximum effectiveness of inhibition oviposition was recorded by using P. granatum leaf powder (75.06 %) compared to O. europaea (53.11 %). A decrease in adult exit was reported among the treatments and the maximum decrease was noticed in the dry white beans with the highest dose rate leaves powder of P. granatum (68.19%) and O. europaea (52.38%). Results obtained from this study revealed that the used plant leaf powders significantly reduced the infestation and the weight loss for white kidney bean. However, P. granatum had higher activity against A. obtectus than O. europaea. There is no doubt that both plants under study have a significant effect on the pest, and accordingly, they can be used in the production of environmentally friendly plant-based insecticides.