THE INFLUENCE OF HARVESTING APPLIED AT DIFFERENT STAGES OF PLANT DEVELOPMENT ON Hyssopus officinalis L. PRODUCTION

The yield and quality traits of hyssop (Hyssopus officinalis L.) depending on the plant developmental phases were investigated under Turkey’s Eskisehir ecological conditions in 2019 and 2020. The experiment were conducted in randomized complete block design with 3 replications. The developmental stages examined were before-flowering, beginning of flowering, full flowering and after flowering stage. The effect of harvest times on examined all parameters was very significant (p ≤ 0.05). The maximum yields of fresh herb and dry leaf + flower were obtained from after-flowering stage. However, no significant difference was observed between full flowering and after-flowering period for dry leaf + flower yield. On the other hand, the essential oil content (0.93%) and essential oil yield (24.01 L ha–1) in the full flowering stage were found to be higher. The main components of hyssop essential oil were as follows: pinocamphone (38.41–41.85%), isopinocamphone (22.73–22.99%) and β-pinene (7.92–8.94%). Maximum pinocamphone content was observed in the before-flowering period. To harvesting in full flowering of hyssop plant can be a reasonable strategy in terms of high dry leaf + flower yield, essential oil content and yield.