The Effect of Indoleacetic Acid and Indole-3-Butyric Acid Concentrations on the Rooting and Growth of <i>Thymus atlanticus</i> Cuttings

Abstract

Abstract This study aimed to evaluate the effect of indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA) concentrations (0 ppm, 300 ppm, 500 ppm, 750 ppm, 1000 ppm, and 1500 ppm) on root development and sprouting of Thymus atlanticus stem cuttings. The results showed a significant effect of auxin type and concentration on survival rate, rooting percentage, root and shoot length, number of shoots, fresh and dry weight. The most efficient was IBA at 1000 ppm, which resulted in a survival rate of 62%, a rooting percentage of 57%, a shoot length of 7.5 cm, and 3.1 new shoots per cutting. These findings highlight the potential of IBA to improve the propagation of Thymus atlanticus using 3–4 cm long shoots, with has important implications for commercial propagation and ecological rehabilitation.