Chemical Composition and Activity of Essential Oils of Albanian Coniferous Plants on Plant Pests

Abstract

The present study was conducted to evaluate and compare the chemical composition and bioactivity of essential oils on different insect organisms from four Albanian coniferous plants. The phytochemical analysis carried out using GC-MS showed that the oils were constituted mainly by monoterpenes, sesquiterpenes and diterpenes. Chemical analysis identified 16 constituents in black pine and silver fir, and 17 constituents in Douglas fir, whereas the analysis allowed identification of 28 constituents in juniper berry. Main constituents of the essential oils included α-pinene and c-verbenol in black pine; β-pinene, α-fenchone and α-pinene in Douglas fir; limonene, β-pinene, α-pinene and camphene in silver fir; and α-pinene, sabinene and β-myrcene in juniper berry. The oils showed varying degrees of insecticidal activity. Juniper berry and silver fir affected the settling behavior of the aphids Myzus persicae and Rhopalosiphum padi, respectively. Black pine oil presented significant activity against the tick Hyalomma lusitanicum and the root-knot nematode Meloidogyne javanica. The ixodicidal effect of this essential oil was explained by its content in c-verbenol, whereas the compound and binary combinations of α-pinene and c-verbenol were not nematicidal, suggesting synergic effects between minor components of black pine essential oil.

Keywords

• coniferous plant
• essential oil
• insecticidal
• ixodicidal
• nematicidal