Rooting of Adult Stem Cuttings of Cupressus sempervirens L. ‘Stricta'

Cupressus semperviens L. ‘Stricta’ (Italian cypress), native to the eastern Mediterranean region, is widely cultivated as an ornamental tree all over the world because of its evergreen, drought, heat, and salt tolerance, wide pH adaptability, and narrow-upright habit. To meet the increasing market demand, we carried out the rooting experiment of adult stem cuttings in January 2013 and treated them with K-IBA at 1000, 3000, 8000 mg/L and talc Hormodin #1, #2, #3. Rooting hormone had significant effects on rooting of Italian cypress and all treated cuttings had greater rooting percentages and longer total root length than that of the control after six months. The highest rooting percentage, 56.3%, was obtained under the treatment of K-IBA at 3000 mg/L and both higher and lower concentrations reduced the rooting percentage and rooting quality. Cuttings treated with powdery hormone had rooting percentages from 37.5%, 25.0%, and 53.1% for Hormodin #1, #2, #3, respectively. Hormodin #3 treatment also produced the highest number of roots (24) per cutting and K-IBA at 3000 mg/L had the longest total length of roots (96.8cm). Growers should apply 8000 mg/L IBA-talc or 3000 mg/L K-IBA to root adult stem cuttings of Cupressus semperviens ‘Stricta’.  It is possible to had higher rooting percentage with juvenile stem cuttings and post-chilling period for adult stem cuttings.