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Evaluation of the Insecticidal Activity of the Aerial Part of Pseudocytisus integrifofius （Salisb） Rehder on Grain Borer, Rhyzopertha dominica Fab, （Bostrychidae） and Wheat Weevil, Sitophilus granarius Linn, （Curculionidae）

This study aims to evaluate the potentialities of Pseudocytisus integrifolius （Salisb） Rehder （Brassicaceae） as a botanical insecticide for the protection of stored wheat against two pests of stored grain. The essential oil of Pseudoeytisus integrifolius was tested at different doses on adults of Rhyzopertha dominica Fab. （Bostrychidae） and Sitophilus granarius Linn. （Curculionidae）, at a temperature of 28 ~C and a relative humidity of 75%. This oil has insecticidal activity and gives, for the studied adults, a very significant reduction. The essential oil extracted from Pseudocytisus integrifolius is toxic on Rhyzopertha dominica with LDs0 = 2.61 ~tL/30g grain and LDs0 = 3.99 ~L/30g grain for Sitophilus granarius, the chemical composition analysis shows the richness of the essential oil compounds known for their insecticidal properties as dimethyl disulfide （DMDS） and dimethyl trisulfide explains the results.