Toxicity of some chemical compounds on aphids, Aphis gossypii, glover and whitefly, Bemisia tabaci, genn. infesting cotton plants and its associated natural enemies

Effect of some chitin-synthesis inhibitors (diafenthiuron and buprofezin), and the dinitromethelin derivative Amidor (imidacloprid) and the mineral oil (KZ-oil) against the cotton aphid, Aphis gossypii. In addition it was planned to evaluate the initial and residual effect of Anjio (thiamethoxam + lambdacyhalothrin), Amidor (imidadoprid) and KZ-oil, on the whitefly Bemisia tabaci (adult and immature stages) and their associated natural enemies. Results showed that imidacloprid induced the highest initial and residual reduction giving (95.8 - 98.8%) in the first season and (96.8 - 98.9%) in the second season against the cotton aphid, while buprofezin (Applaud) came in the second order recording (80.5 - 90.3%) in the first season, and (80.3 - 88.7%) in the second season. While, the initial and residual activity of diafenthiuron (Polo) was (68.5 - 90.9% reduction ) in the first season and (66.02 - 84.9%) in the second season. KZ - oil induced a moderate initial and residual effect, where it exhibited (63.7 - 64.6%) and (65.1 - 65.3%) reduction in the two seasons respectively. As for the effect of thiamethoxam+ lambdacyhalothrin, imidacloprid and KZ - oil against the white fly S. tabaci mature stage , thiamethoxam+ lambdacyhalothrin induced the highest initial reduction giving 73.3' and 76.3% in the two seasons respectively, followed by Amidor (72.7 and 69.9%, respectively) and KZ - oil (68.5 and 69.1% respectively). While, thiamethoxam+ lambdacyhalothrin induced the nighest residual activity (80.03 and 78.1% reduction) in the two seasons respectively, followed by KZ - oil (72.2 and 74.9% reduction) and thiamethoxam+ lambdacyhalothrin (70.8 and 70.9% reduction) in the two seasones , respectively. Regarding the effect on immature stage thiamethoxam+ lambdacyhalothrin induced the highest initial effect in the two seasons (76.2 and 86.3% reduction) respectively, followed by imidacloprid and KZ - oil which gave (71.9 and 59.9% reduction) and (72.2 - 64.8% reduction) in the first and second seasons..