Essential oils of Tunisian Pinus radiata D. Don, chemical composition and study of their herbicidal activity

Little is known about the phytotoxic effects of essential oils from Pine species, GC and GC/MS analysis of Pinus radiata D. Don essential oil obtained from needles, resulted in the identification of 49 components comprising 97.6 % of the oil totality. The composition was l dominated by monoterpene hydrocarbons (86.4 %) with β-pinene (40.2 %), limonene (25.5 %) and α-pinene (15.2 %) were the major compounds. On the herbicidal activity, the oil strongly inhibited seed germination and seedling growth of all tested weeds in a dose dependent manner with the effect being significantly more effective on dicots (Sinapis arvensis L. and Trifolium campestre Schreb) than monocots (Phalaris canariensis L.).