SELECTION OF ENVIRONMENTALLY SAFE COMPOUNDS FOR CONTROLLING THE COTTON LEAFWORM, Spodoptera littoralis (BOISDUVAL) IN BELL PEPPERS AT MENOFIA GOVERNORATE UNDER SEMI-FIELD CONDITIONS

Capsicum annum L., more often known as the bell pepper, is a staple fruit vegetable crop grown worldwide due to its high nutritional value. Spodoptera littoralis (Boisduval), often known as the cotton leafworm, causes substantial economic losses and detrimental effects on crop quality of its voracious appetite. Biopesticides as an alternative to traditional insecticides for S. littoralis management have recently received more focus. We examined three commercial bioinsecticides at the recommended concentrations against S. littoralis 2nd instar larvae during two growing seasons in semi-field circumstances. Larval mortality was observed three days post-treatment for all drugs. Although all tested compounds were effective, emamectin benzoate consistently produced the greatest death rate over both planting periods. More importantly, in both growing seasons, the virulence of the investigated compounds was maintained for up to 10 days after treatment. Results showed that Bio-Power® exhibited the highest LC50 value (1.156 gm/ml), followed by Biotect® (0.1238 gm/ml) and Benzo® (0.0084 gm/ml). Furthermore, treatment with sublethal concentrations of the tested compounds lowered the total proteins, carbohydrates and lipids compared to the control. On the other hand, certain carbohydrate hydrolyzing enzyme levels were significantly reduced due to the treatment of the 2nd instar larvae with the LC50 of the investigated substances. While treatment with the sublethal concentration of tested compounds increased the GST level compared to the control, the chitinase activity was reduced. The results of this study show that bioinsecticides are effective replacements for synthetic insecticides. They are safe to use and have a pathogenic effect on insects, so you may use them without worrying about harming anyone.