Fumigant activity of plant essential oil from Armoracia rusticana (L.) on Plodia interpunctella (Lepidoptera: Pyralidae) and Sitophilus zeamais (Coleoptera: Curculionidae)

The fumigant toxicity of essential oil from horseradish plant, Armoracia rusticana (L.), was assessed against Plodia interpunctella (Hübner) and Sitophilus zeamais Motschulsky. A. rusticana oil was active against different life stages of P. interpunctella and adults of S. zeamais. The LC50 value for adults was the lowest and that of pupa was the highest. The major compound found by gas chromatography-mass spectrometry was allyl isothiocyanate (97.81%). These results indicate that it may be possible to achieve toxicity levels similar to those of standard chemical fumigants through the applications of essential oils from A. rusticana.Key word: Plant essential oil, Plodia interpunctella, Sitophilus zeamais, fumigant activity, allyl isothiocyanate