Seasonal variations in the composition of Pinus halepensis and Pinus sylvestris twigs and needles essential oil

SUMMARY Influence of season on the terpene composition of Pinus halepensis and Pinus sylvestris was investigated. The essential oil of twigs and needles from a preselected plot of pines was investigated from October to June. In P. halepensis, the average composition during this time was 27·2% α-pinene, 65·0% sabinene, 7·2% 3-carene and 0·5% β-pinene in the essential oil of twigs; 32·1% α-pinene, 35·9% sabinene, 18·5% terpinolene, 4·3% 3-carene, 3·1% β-pinene and 6·1% thujene, limonene, β;-phellandrene and γ-terpinene in the essential oil of needles. In P. sylvestris, the average composition was 49·2% α-pinene, 30·1% sabinene, 14·9% β-pinene and 7·9% limonene in the essential oil of twigs; 69·5% α-pinene, 14·9% camphene, 9·1% β-pinene, 3·6% sabinene and 2·8% limonene in the essential oil of needles. The maximum amount of sabinene coincides with the minimum of α-pinene, both in twigs and needles essential oil from P. halepensis and P. sylvestris. The month-to-month changes in the oil composition are statistically significant for the most part. It is of interest to point out the decrease of sabinene content of needles essential oil in comparison with the twigs essential oil, with the simultaneous increaseof terpinolene in P. halepensis and camphene in P. sylvestris.