The rooting capacity of red tip photinia; Photinia × fraseri hardwood cuttings under the effects of cutting time and IBA concentration

Abstract

The experiment was conducted at the lath house in the nursery of Bakrajo Technical Institute campus, Sulaimani Polytechnic University, Bakrajo, Sulaimani city, Iraq, during 2021-2022, in order to study the effect of the date of taking cuttings (October 15^th, November 15^th, and December 15^th) and IBA (Indole-3-butyric acid) concentration (0, 2000, 4000 and 6000 mg. L^-1) on rooting, some vegetative and root growth characteristics of red tip photinia, Photinia x fraseri. A two-factor experiment was carried out according to a complete randomized design (CRD) with three replications. The results showed that the cuttings taken on November 15^th were significantly superior in most of the studied parameters; rooting percentage (10.0%), shoot length (7.00 cm), number of shoots per plant (1.0), number of leaves per plant (5.0), average leaf area (21.07 cm²), shoot fresh weight (1.32 g), shoot dry weight (0.39 g), shoot diameter (1.95 mm), longest root (7.33 cm), average root number per plant (1.67), root fresh weight (0.55 g) and root dry weight (0.20 g). While, IBA at 6000 mg. L^-1 caused significant differences in most of the previously mentioned parameters, giving the values 43.33%, 25.67, 1.67, 15.33, 77.28, 13.61, 5.39, 4.31, 27.33, 6.33, 2.48, and 0.71 respectively. Additionally, the interaction between the three cutting times; (October, November and December) and four concentrations of IBA; (0, 2000, 4000, 6000 mg. L^-1), the interaction of concentration 6000 mg. L^-1 of IBA and the date November 15^th showed significant superiority in all studied parameters.