Chemical analysis, isolation and insecticidal activity of bioactive compounds of citronella essential oil for management of Bemisia tabaci (Gennadius) on Bt cotton

In search for an eco-friendly and comparatively safe insecticide, citronella essential oil (CEO) and isolated terpenoids were evaluated against Bemisia tabaci (Gennadius) on Bt cotton during the years 2022 and 2023. The CEO was extracted from the leaves of Cymbopogon nardus and analysed. Citronellal and Citronellol were isolated from CEO via silica gel column chromatography and characterised using NMR and IR. The application of CEO significantly reduced the damage caused by B. tabaci on cotton in a concentration-dependent manner, which was comparable to the standard azadirachtin in both multiple-choice and no-choice conditions. The CEO and isolated terpenoids showed repellent, toxic and oviposition deterrent effects. The activity of monoterpenoids alone was comparatively lower than CEO. Our results provided the possibility that the CEO can be successfully employed as a botanical insecticide in integrated pest management for the control of B. tabaci.