EFFECTS OF NEEM SEED KERNEL EXTRACTS ON EGG AND LARVAL SURVIVAL OF THE SORGHUM SHOOT FLY, ATHERIGONA-SOCCATA RONDANI (DIPT, MUSCIDAE)

A two-year study was conducted to evaluate the effects of neem extract s on egg and larval mortality of the sorghum shoot fly, Atherigona soc cata Rond. Field experiments were conducted in 1990 and 1991 in a sorg hum field at Matourkou (Burkina Faso, West Africa). The following trea tments were applied: 1. carbofuran 5 G, 2. 20 kg/ha neem seeds/500 1 w ater, 3.20 kg/ha neem seeds/500 1 water + 2.5 1/ha adhesol, 4. 30 kg/h a wild neem seeds/500 1 water + 2.5 1/ha adhesol, 5. 2.5 1/ha adhesol, 6. control (untreated plots). Significant differences among treatment s were observed in the number of eggs laid, and the percentage of dead hearts. Significantly fewer eggs and dead hearts were observed in plo ts' treated with neem extracts compared with adhesol and control. In t he laboratory, the treatments were: 1. commercial neem oil containing 0.63 % azadirachtin, 2. local neem oil, 3. 40 g seed kernels/1/water, 4. 40 g seed kernels/1 water + 5 ml adhesol, 5. 60 g seed kernels/1 wa ter + 5 ml adhesol, 6. 5 ml adhesol/1 water, 7. control (untreated egg s). All neem seed extracts gave a significant lower percentage of egg hatching than the adhesol and control treatments. In larval survival e xperiments, commercial and local neem oil were not used. All treatment s showed a significantly higher larval mortality compared with the con trols.