The effect of different harvest dates on the yield and quality properties of rosemary (Rosmarinus officinalis L.) plant

Abstract

The purpose of this research carried out in 2018 under Eskişehir ecological conditions was to determine the effect of six different harvest dates (T1: 16 August, T2: 29 August, T3: 14 September, T4: 28 September, T5: 15 October and T6: 31 October) on the yield and quality properties rosemary (Rosmarinus officinalis L.). The experiment was established according to a randomized complete-block design with four replications. The composition of the essential oil obtained by the hydro-distillation from the dry leaves of the rosemary plant was analyzed by GC-MS. In the experiment carried out, the mean values of plant height (cm), fresh herb yield (t ha), dry herb yield (t ha), dry leaf yield (t ha), essential oil ratio (%), essential oil yield were determined as 61.87 cm, 15.78 t ha, 5.80 t ha-1, 3.55 t ha, 0.69% and 23.92 l ha, respectively. In the essential oil samples obtained from the harvests made at different dates, 35 different components were identified. The values of the camphor, 1-verbenone, α-pinene, borneol and 1,8-cineol components determined as the main component in the analyzed essential oil samples ranged from 11.67 to 14.78%, from 8.47 to 11.77%, from 8.74 to 11.82%, from 8.61 to 11.12% and from 7.01 to 9.07%, respectively.