COMPATIBILITY BETWEEN BEAUVERIA BASSIANA AND LECANICILLIUM MUSCARIUM TO CONTROL THE COTTON WHITEFLY AND THEIR EFFECT ON THE PARASITOID ERETMOCERUS MUNDUS *

Abstract

Data in terms of the efficacy of the local isolate of the fungus B. bassiana (9.6 x 107 conidia/ ml. conc.), fungal formulation of Lecanicillium muscarium (1 gm/ L conc.) and their mixture which were sprayed on eggplant (Iraq Wonder variety) to control cotton whitefly Bemisia tabaci, indicated that after one week of application, the mixture of the two fungi caused 94.35% mortality in nymfal stages of cotton whitefly. This result was statistically superior in comparison to mortality rates obtained from amounted to 86.85 and 86.75% respectively. As regard to the interaction among the three treatments with weeks results showed superior of the mixing of B. bassiana with the preparation of the fungus L. muscarium at the second week (with 99% mortality) on the treatment of the fungus and the preparation alone at the first week (with 79.3 and 75.7% mortality respectively). Results revealed that the local isolate of the fungus B. bassiana is relatively more dangerous on the parasitoid, Eretmocerus mundus, than fungal formulation of L. muscarium. Results also showed that the direct spraying or exposure of this parasitiod adults to the fungus L. muscarium were non-significantly effected on mortality rates which reached to 30.14 and 25.78% respectively.