Effects of Melia azedarach leaf extracts on nutritional behavior and growth of Spodoptera littoralis. Akacha, M., Chaieb, I., Laarif, A., Haouala, R., and Boughanmi, N. (Tunisia)

Abstract

Synthetic chemicals used nowadays as insecticides caused many negative effects (pollution, toxicity…) which led to an increasing interest in botanical insecticides because of their minimal costs and less ecological side effects. In this respect, the activity of Melia azedarach leaf extract against the third stage larvae of armyworm (Spodoptera littoralis) has been assessed in this study. The aqueous and ethanolic extracts exhibited an antifeedant activity against S. littoralis larvae according to the applied doses. Ethanolic extract reduced the food consumption and digestibility inducing growth rate decrease of the armyworm larvae. An increase in the larval stage duration was also observed as well as anomalies. Pupation stage was affected and occurred only for the lowest doses with a significant decrease in pupa weight. Consequently, ethanolic M. azedarach leaf extract may be used in the alternative control strategies against S. littoralis pest.

Keywords

• Biopesticide
• ethanolic extract
• Melia azedarach
• Spodoptera littoralis