Penicillin (Alternanthera brasiliana (L.) Kuntze) belongs to the Amaranthaceae and has been recognized for its anti-inflammatory, analgesic and antiviral properties. This study aimed to evaluate the most appropriate concentration of indole butyric acid (IBA) to induce rooting of penicillin cuttings. We selected herbaceous branches, collected in November of 2010, to prepare 6 cm long cuttings with two apical leaves and disinfected them in solution of sodium hypochlorite (0.5%) for 15 minutes. Then, the penicillin cuttings had their bases immersed for 10 seconds in IBA at the concentrations of 0, 250, 500, 750 or 1000 mg L-1, planted in small plastic tubes, irrigated and maintained in a greenhouse. The experimental design was completely randomized, with 80 cuttings per treatment. After 30 days, we observed no significant different results among treatments on rooting, root growth, mortality, fresh and dry mass. There was an increase in the number of roots in the cuttings immersed in higher concentrations (750 and 1000 mg L-1) of IBA compared to the control and other treatments. The rooting percentages were above 94% for this species, and we could conclude that the propagation by cuttings is feasible without the use of regulators to induce root formation in this species, which can be considered as easy to root.
Rooting; auxin; vegetative propagation; medicinal plant
