Abstract
The toxicity of five bioinsecticides on the Egyptian cotton leafworm (Spodoptera
littoralis) were evaluated under laboratory conditions. These bioinsecticides were Metarhizium anisopliae (Bio- Meta 2.5% WP), Beauveria bassiana (Bio-Ciana 2.5%WP), Bacillus thuringiensis (Protecto 9.4% WP), emamectin benzoate (Excellent 1.9% EC) and Spinosad (Tracer 24%SC). All experiments were evaluated on 4th larval instar to determine the LC values of the tested compounds. The biochemical parameters were also recorded on the 4th larval instar after 72h. The LC50 of these compounds were 30.45, 38.61, 21.15, 7,98 and 9.22 ppm after 72h for the above-mentioned compounds, respectively. The results clearly indicated that Excellent was the most effective compound, while Bio-Ciana was the least effective compound. Also, the results indicated that, all treatments reduced total protein, total lipids, glucose contents, alkaline phosphatase (AKP), and acetylcholinesterase (AChE) significantly (P < 0.05) in comparison with untreated check (control), while acid phosphatase (ACP) activity was decreased only after treatment with Bio-Meta, Excellent and Tracer. On the other hand, glutamic pyruvic transaminase (GPT) activity showed a significant increase (P< 0.05) with all treatments except Bio-Meta. Similarly, glutamic oxaloacetic transaminase (GOT) activity was increased with all treatments except Bio-Meta and Bio-Ciana. The results concluded that Excellent and Tracer were the most effective and can be successfully developed for controlling the Egyptian cotton leafworm.