A Laboratory Study on The Toxicity of Some Insecticides Against The California Red Scale, Aonidiella aurantii on Mandarin Leaves in Qena Governorate, Egypt

Citrus trees are an important strategic crop in Egypt grown in large areas with high productivity. As a result of climatic changes during this period, it was attacked by several pests causing heavy losses, whereas, California red scale (Aonidiella aurantii) is one of the most challenging pests to control in citrus orchards. In this laboratory study, we evaluated the toxic effect of nine selected insecticides, namely Daikon-lambada (10% WP), Aceta gold (20% WP), Acetampride, Malatox (57% EC), KZ oil (95% EC) + Malatox (57% EC), Metarhizium anisopliae (2.5% WP), IGR (0.5% EC), KZ (95% EC) + IGR (0.5% EC), KZ oil (95% EC) and Clean Touch (5% WP) against A. aurantii on mandarin leaves. It can be concluded that adult numbers have systematically decreased over time after spraying up to two weeks of treatment. The four insecticides KZ oil + Admiral,KZ oil + Malatox, KZ oil and Malatox were the most effective insecticides with a lethal effect against adult insects while increasing the from one day to two weeks after treatment. The highest mean reduction percentages of A. aurantii at adult stage (71.65, 58.75, 58.45 and 53.30 %) were recorded as result of applying the insecticides. The highest meanreduction percentages of pre-adult insects 66.31, 61.77, and 52.11% were recorded with KZ oil + Admiral, KZ oil, and KZ oil + Malatox, respectively. The study suggested introducing tank mixtures of KZ oil + Admiral, KZ oil, and KZ oil + Malatox, to minimize the development of pesticide resistance, it should prepare the management program on alternate insecticide combinations after determine the optimal timing and targeting vulnerable life stages to enhance sustainable California Red Scale management.