Evaluation of the potential toxicity of plant extracts, pathogenic fungi, and chemical pesticides for the management of Spodoptera frugiperda

Abstract Fall armyworm , S. frugiperda (Lepidoptera: Noctuidae), is a highly invasive and polyphagous pest. The current study aims to utilize effective, environmentally friendly, and safer products for combatting insects while reducing the use of chemical agents. The toxicity of plant extracts (camphor, castor, and oleander), fungi ( T. harzianum ), and chemical control (emamectin benzoate) against the third larval instar of S. frugiperda was evaluated under laboratory conditions. Data showed that the oleander extract at a concentration of 20 g/l was the most toxic among the tested extracts, recording an 86.6% mortality (LC 50 = 7.04 g/l). T. harzianum also showed high effectiveness against S. frugiperda , recording an 80% mortality (LC 50 = 2 × 10 7 conidia/ml) at both 6 × 10⁷ and 8 × 10 7 conidia/ml concentrations. Emamectin benzoate exhibited toxicity on S. frugiperda larvae, with 100% mortality recorded (LC 50 = 0.21 g/l), at a concentration of 0.8 g/L.