Promotion of Adventitious Root Formation on Cuttings by Paclobutrazol

The promotion of adventitious root formation by paclobutrazol was tested by placing cuttings in solutions of the chemical for 24–40 hr, and then observing the rooting response. Paclobutrazol at relatively low concentrations (3 to 6 mg·liter -1 ) increased the number of roots formed on cuttings of Creeping Charlie ( Plectranthus australis R. Br.) and common bean ( Phaseolus vulgaris L.) by about 100% and 85%, respectively. Paclobutrazol did not affect root length greatly but reduced shoot length by about 20% compared to controls.