International Journal of Environment and Climate Change

The experiment was conducted at the field of the Division of Floriculture and Landscape Architecture, Sher-e-Kashmir University of Agricultural Science & Technology, Shalimar Srinagar. The design of the experiment was CRD with 3 replications to evaluate the influence of different concentrations of Indole-3-butyric acid (IBA) and seasonal timing on the rooting performance of variegated Nerium oleander L. cuttings. Five treatments comprising 0 ppm (control), 500 ppm, 1000 ppm, 2000 ppm, and 3000 ppm IBA were applied to semi-hardwood cuttings during different seasons to assess their effect on rooting percentage, root number, root length, and plant growth. The treatment produced the highest number of primary roots (2.12, 12.56), secondary roots (5.32, 25.65), root length (3.32 cm, 11.67 cm), rooting percentage (10%, 95%) diameter of primary root (0.02mm, 0.8mm) survival% (30%, 95%) in variegated nerium in summer season respectively. It also resulted in the shortest days to rooting in summer season 20.12 days and35.73 days in autumn season. The highest biochemical contents were observed in summer season cuttings treated with IBA at 3000 ppm yielding the maximum total nitrogen (1.00%, 3.20%) and (1.24%, 7.24%) sugar contents. Phenol content was found highest (1.00%, 1.64%) insummer season cuttings treated with IBA at 3000 ppm. Results indicated that both IBA concentration and season significantly influenced the rooting parameters. Among the treatments, 3000 ppm IBA showed the highest rooting percentage, longest root length, and maximum number of roots per cutting, particularly when applied during the summer season. Seasonal variation played a crucial role, with spring and early summer favouring better rooting compared to autumn. The study highlights the importance of optimizing both IBA concentration and timing to achieve efficient propagation of variegated Nerium oleander L., thus providing valuable insights for commercial production and landscape utilization.