Efficacy of Mandarin Crust Oil, Marigold Extract and Their Nanoemulsions, on Spodoptera littoralis (Boisd.) Larvae

Abstract

Background and Objective: In recent years, nanoemulsions have been used to target pest toxicity due to the dangers of chemical pesticides. The current study investigated the insecticidal activity of the mandarin crust oil (Citrus reticulata) and marigold extract (Calendula officinalis L.) in the form of nanoemulsions formulations and plant oil against 2nd instars larvae of Spodoptera littoralis. (Boisduval). Materials and Methods: To assess the toxicity of treatments to 2nd instar larvae, the leaf-dipping technique was used. The toxicity was recorded after one, three, five and seven days post-treatment and LC50 values were calculated. Results: The results indicated that nanoemulsion of plant oil extracts has the highest insecticidal activity against S. littoralis, followed by plant oil extracts. The major constituents identified by GC-MS analysis in marigold extract and mandarin crust oil were, 6-epi-shyobunol (Longiborneol) and D-Limonene, respectively. Furthermore, at LC50, all treatments decreased AST/GOT and ALT/GPT activity, showing a significant reduction in creatinine activity when compared to control. Conclusion: According to the current study, the use of the nanoemulsion formulation could be useful in integrated pest management programs.