Essential oils of lippia species in Kenya. IV: Maize weevil (Sitophilus Zeamais) repellancy and larvicidal activity

Abstract

The repellancy of essential oils of eight Lippia species on maize weevils was compared with N.N-diethyltoluamide (DEET). The larvicidal activity of these essential oils was also examined. As a repellant, the essential oil of L. ukambensis (chemotype camphor) was the most active. Other prom¬ising repellants were the essential oils of L. javanica, L. dauensis, L. somalensis and L. grandifolia. The essential oil of L. wilmsii was the most active as a larvicide. Individual hydrocarbon monoterpene constituents were generally more active than the oxygenated constituents of the essential oils.