Insecticidal activity of Lavandula angustifolia Mill against the pea aphid Acyrthosiphon pisum
Sabrine Attia, Georges Lognay, Stéphanie Heuskin, Thierry Hance
The essential oil of Lavandula angustifolia was investigated for its biocide activity against Acyrthosiphon pisum by fumigation. The oil was characterised by GC-MS revealing that linalool was the most abundant component (38.57%), followed by linalyl acetate (29.95%), 1,8-cineole (13,66%), camphor (13,13%), β-pinene (3,14%) and terpinene-4-ol (1,54%). The Mortality was measured upon treatment with oil concentrations ranging from 5 to 25 µl.l-1 of air. The mortality of aphids increased with oil concentration and LC50 values were determined to be 11.2 µl.l-1 of air. The full mixture was also prepared and toxicity was compared with individual constituents. The results showed that the presence of all constituents were necessary to equal the toxicity of the natural oil. L. angustifolia oil can provide valuable pesticide activity with significantly lower LC50 values.