Evaluating the Efficiency of Some Biocides and Spore Suspensions in Controlling the Cotton Aphid, Aphis gossypii on Eggplant

Abstract

The study of the population density of the cotton aphid, Aphis gossypii on eggplant, cv. Badia al-Nasr, showed that the highest density was observed during the month of March, when it reached 80.0, 85.0, 111.5 insect/leaf during early, middle and late periods of the month, respectively. To evaluate the relative efficiency of fungal and bacterial preparations in comparison with the chemical insecticide Actara in controlling the cotton aphis insect A. gossypii in the laboratory, the results showed that the fungal preparation Beauveria bassiana was the most efficient compared to the other preparations used and reached 78. 56, 82.08, 90.00% for B. bassiana, Metarhizium anisopliae and Bacillus thuringiensis, respectively. Control treatment with Actara pesticide reached 90.00%, 7 days after treatment. The relative efficiency of the spores suspensions in the laboratory reached 71.06, 80.16, and 90.00% for Trichoderma harzianum, Cordyceps pseudolloydiis and B. bassiana at concentrations of 18×10⁸, 11×10⁸, and 23×10⁸ spores/ml, respectively, 7 days after treatment. The relative efficiency of the fungal and bacterial preparations in the field experiment reached 71.90, 79.08, and 85.41% for B. bassiana, M. anisopliae and B. thuringiensis respectively. The relative efficiency of the spores suspension, in the field experiment, 7 days after treatment, was 63.44, 73.21 and 76.36 % for T. harzianum, C. pseudolloydiis, and B. bassiana, respectively.

Keywords:

Actara, Aphis gossypii, Cordyceps pseudolloydiis, Tricoderma harzianum, Beauveria bassiana.