The potential of ultrasonic waves for sustainable management of cotton leafworm <i>Spodoptera littoralis</i> (Lepidoptera:Noctuidae)

Physical pest control is effective in integrated pest management, as chemical treatments can be extremely hazardous and cause environmental pollution. One of these physical methods is the use of ultrasound waves in insect pest control. Cotton leafworm Spodoptera littoralis (Boisd.) (Lepidoptera:Noctuidae) causes great harm to a widespread diversity of crops in the Middle East and is one of the main economic pests of Egyptian cotton. Under laboratory conditions, the effect of ultrasound waves on the larval weight gain, food consumption and feces of second and fourth stage of cotton leafworm larvae were recorded, also total protein, total carbohydrate, total lipids and hepatic enzymes glutamate oxaloacetate transferase (GOT/AST), glutamate pyruvate transferase (GPT/ALT) and alkaline phosphatase after 9 days of exposure to ultrasound waves was determined for the 6th instar larvae compared with untreated control larvae. A commercial ultrasonic device was used with a frequency of 50000 HZ. Within an enclosed chamber contains the second and fourth cotton leaf worm larvae are at a distance 20 cm from the device another, chamber in another place contains the untreated larvae (Control). All larvae allow feeding on castor leaf oil. The results show that the larval weight gain, food consumption and feces of the treated larvae were less than the untreated control. The larval weight gain for the second stage larvae were 0.30gm compared with 0.60gm for control along exposure days and 0.47gm for the 4th instar compared with 0.76gm for 4th instar of control food consumption were 0.30gm for the treated second and fourth instar compared with 0.50gm compared with the second and fourth instar control, feces 0.28gm for the second instar compared with 0.42gm feces weight of control and 0.21gm feces for the 4th instar compared with 0.34 gm of control, there is significance disturbance in the tested biochemical parameters and hepatic enzymes show a significant increase as hepatic cells degeneration as compared with untreated control which assures the useful of used of ultrasonic waves as pesticide alternative.