Food consumption, utilization and biochemical impacts of some insecticides on the cotton leafworm Spodoptera littoralis (Lepidoptera: Noctuidae)‎

الملخص EN

This experiment was conducted on the 4th instar larvae of Spodopetra littoralis (Boisd.) (Lepidoptera: Noctuidae) to investigate the impact of some pesticides belonging to different groups in the laboratory to evaluate their antifeedant activity, relative growth rate and utilization of ingested food .

Moreover the effect of the tested compounds on the total protein, total carbohydrate, total lipids and acetylcholinesterase were recorded.

The obtained results clear antifeedant index for owner 5%EC seems to be the most powerfull tested compounds followed by dimilin 48%SC.

Also, the relative growth rate (RGR) of the 4th instar larvae of S.littoralis fed on castor leaves treated with owner 5% was decreased clearly often one day exposure followed by strong 30% SC.

After three days exposure emafel 45% ME achieved the lowest utilization of ingested food (FCI).

Over and above the biochemical studies explained the four tested insecticide represented significant decrease in the amount of total carbohydrate, totalprotein, total lipids and acetylcholinesterase enzyme.

Owner 5% caused the highest change percentage in total lipids (45.12%).

Whereas, dimilin 48%SC cased the highest change percentage in total protein and total carbohydrate (33.07 and 54.6) respectively.

Dimilin was the most inhibitive of acetylcholinesterase activities 28.06 change percentage.