The Singular and Combined Effects of Entomopathogenic Fungi Beauveriabrongniartii and the Insecticide Imidaclorprid against Corn Pests under Laboratory and Field Conditions in Egypt

Under laboratory conditions the LC50 obtained was 132 x104, 144 x104, 170 x104 conidia/ml after Ostrinia nubilalis, Sesamia cretica and Chilo agamemnon treated with different concentrations of Beauveria brongniartii respectivelyWhen the two tested pathogens combined at the sublethal does the LC50 for the corresponding insect pests recoded were significantly decreased to 46, 69 and 75 g/L for O. nubilalis, S. cretica and C. agamemnon. , respectivelyAt the harvest time the corn weight obtained 392254.6 and 311060.4 kg/Feddan among the harvested plots treated with B. brongniartii and imidaclorprid plots as compared to 271040.9 and 251173.2 kg/Feddan during seasons 2012 1nd 2013, respectivelymortality ranged between 69 and 78 % after bioinsecticides treatments.