The insect repellent activity of the essential oils of two tropical Lamiaceae, Hyptis spicigera Lamarck and Hyptis suaveolens (L.) Poitier, and of a Mediterranean one, Lavandula angustifolia (Miller), has been measured against adults of the granary weevil, Sitophilus zeamais Motschulsky (Coleoptera Dryophthoridae). The chemical composition of the three essential oils was also examinated. Results showed that the three essential oils had repellent activity on S. zeamais adults. At the lowest dose (0.001%) H. suaveolens essential oil exhibited a significantly higher repellent effect compared with H. spicigera and L. angustifolia, while no significant differences were observed for the repellent effect of the three essential oils at the highest dose (0.1%). L. angustifolia essential oils evidenced a significantly lower repellent activity at the intermediate dose (0.01%) after 1, 3 and 5 h of exposure. Chemical analyses showed that in the essential oil of H. suaveolens monoterpene hydrocarbons were the most represented class of volatiles (64.1%), followed by sesquiterpene hydrocarbons (24.0%), oxygenated monoterpenes (8.1%) and oxygenated sesquiterpenes (2.4%). In the essential oil of H. spicigera monoterpene hydrocarbons were the most represented class of volatiles (70.4%), followed by sesquiterpene hydrocarbons (22.6%).
Repellence of essential oils from tropical and Mediterranean Lamiaceae against Sitophilus zeamais
CONTI, BARBARA;CANALE, ANGELO;CIONI, PIER LUIGI;FLAMINI, GUIDO
2010-01-01
Abstract
The insect repellent activity of the essential oils of two tropical Lamiaceae, Hyptis spicigera Lamarck and Hyptis suaveolens (L.) Poitier, and of a Mediterranean one, Lavandula angustifolia (Miller), has been measured against adults of the granary weevil, Sitophilus zeamais Motschulsky (Coleoptera Dryophthoridae). The chemical composition of the three essential oils was also examinated. Results showed that the three essential oils had repellent activity on S. zeamais adults. At the lowest dose (0.001%) H. suaveolens essential oil exhibited a significantly higher repellent effect compared with H. spicigera and L. angustifolia, while no significant differences were observed for the repellent effect of the three essential oils at the highest dose (0.1%). L. angustifolia essential oils evidenced a significantly lower repellent activity at the intermediate dose (0.01%) after 1, 3 and 5 h of exposure. Chemical analyses showed that in the essential oil of H. suaveolens monoterpene hydrocarbons were the most represented class of volatiles (64.1%), followed by sesquiterpene hydrocarbons (24.0%), oxygenated monoterpenes (8.1%) and oxygenated sesquiterpenes (2.4%). In the essential oil of H. spicigera monoterpene hydrocarbons were the most represented class of volatiles (70.4%), followed by sesquiterpene hydrocarbons (22.6%).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
