Compositional analysis and toxicity of four plant essential oils to different stages of Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

Abstract

Experiments were conducted to investigate the biological effects of essential oils from basil (Ocimum basilicum L.), paprika (Capsicum annuum L.), peppermint (Mentha x piperita L.) and rosemary (Rosmarinus officinalis L.) on the different stages of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Essential oils were obtained by Clevenger-type water distillation and analyzed by capillary gas chromatography-mass spectrometry. The doses of the essential oils applied were 0.1, 1, 5, 10, 20, 50 and 100 μl L-1 air. The major compounds of the essential oils were detected as linalool (63.1%), capsaicin (35.4%), menthol (28.3%) and cineole (25.7%), in basil, paprika, peppermint, and rosemary oils, respectively. The essential oil of paprika caused the highest mortality of first instar larvae of E. kuehniella at a dose of 5 μl L-1 air after 24 h exposure. Among the tested different stages, larvae of E. kuehniella were the most tolerant of essential. Basil, paprika, peppermint and rosemary oils exhibited toxicity to adult stages of E. kuehniella with 100% mortality obtained after 24 h at dose of 100, 5, 20 and 10 µl L-1 air, respectively. Increasing the doses of essential oils resulted in increased toxicity to all stages of E. kuehniella. In conclusion, the four plants essential oils tested in this study have potential for use in the management of the stored-product pest, E. kuehniella.