Chemical composition and toxicities of essential oil of Illicium fragesii fruits against Sitophilus zeamais
The aim of this research was to determine the chemical composition and toxicities of essential oil derived from Illicium fargesii Finet et Gagnep fruits against the maize weevil (Sitophilus zeamais Motsch). Essential oil of I. fargesii fruits was obtained from hydrodistillation and was investigated by GC (Gas Chromatography) and GC–Mass Spectrometry (GC-MS). A total of 43 components of the essential oil of I. fargesii fruits were identified. The principal compounds in I. fargesii essential oil were α-terpineol (11.4%), carvone (10.9%), d-limonene (9.8%), trans-carveol (6.6%) and trans-pinocarveol (5.5%). The essential oil of I. fargesii possessed strong fumigant toxicity against the maize weevil with an LC50 value of 11.36 mg/L air. The essential oil of I. fargesii also exhibited contact toxicity against S. zeamais adults with an LD50 value of 28.95 μg/adult. The result indicate that the essential oil of I. fargesii show potential in terms of fumigant and contact toxicities against grain storage insects.
Key words: Illicium fargesii, Sitophilus zeamais, fumigant, contact toxicity, essential oil composition.