Comparison of the insecticidal activity of calcium borate with mushroom-like structures and chitin synthesis inhibitor insecticide (Dimilin) against Egyptian cotton leaf worm

Abstract

Egyptian cotton leaf-worm (Spodoptera littoralis) is one of the most destructive phytophagous insects not only in Egypt but also in the whole world. The extensive application of synthetic organic insecticides against Spodoptera littoralis (S. littoralis) cause raising resistance toward several insecticides. Thus, developing of an alternative novel class of insecticides is an urgent assignment. Herein, calcium borate nanoparticles (CB-NPs) with mushroom-like structures were synthesized via template assisted-hydrothermal route and applied against S. littoralis for the first time. The larvicidal activity of CB-NPs was investigated and compared with the insect growth regulator (dimilin), the calculated LC50 values were 192.72 mg/L and 19.59 mg/L for CB-NPs and dimilin, respectively. The examination of the histological influences for cross-sections of 6th instar larvae showed a similar action mechanism on the cuticle layer for CB-NPs and dimilin. Thus, CB-NPs could be utilized in the agricultural programs instead of dimilin.