Substrate composition and indolebutyric acid on the propagation of Eplingiella fruticosa from cuttings

Eplingiella fruticosa (Salzm. ex Benth.) Harley & J.F.B. Pastore, also known as "alecrim de vaqueiro" or "cowboy rosemary", is a woody, perennial, and aromatic shrub that growsin the states of northeast Brazil, with the exception of Alagoas, Maranhao, and Piaui. The plant is widely used in this region and has analgesic, vasodilator, anti-inflammatory, and larvicidal properties. The objective of this study was to evaluate the effect of different substrates and indolebutyric acid (IBA) on cuttings of E.fruticosa for identifying effective practices for the vegetative propagation of this species. Apical cuttings with a standardized length of 10cm and two pairs of leaves were harvested from mother plants in the vegetative stage. Two experiments were conducted: the first experiment tested the effect of three substrates (commercial, commercial + vermiculite, and commercial + vermiculite + humus) and the second experiment evaluated five concentrations of IBA (0.0, 1.0, 2.0, 3.0, and 4.0gL(-1)) and three growth periods (30, 45, and 60 days). The experimental design was randomized blocks with four replications. The analyzed variables were survival of cuttings, number of rooted cuttings, root length per cutting (RLC), number of buds per cutting (NBC), leaf dry mass (LDM), root dry mass (RDM), and total dry mass (TDM). In thefirst experiment, there were significant differences in RLC, NBC, LDM, RDM, and TDM, with a better growth using the commercial substrate. In the second experiment, there was no interaction between the evaluated parameters. However, there was a positive associated effect of IBA addition and the growth period on RLC, NBC, LDM, and RDM. The highest predicted value was attained for a concentration of 1.5g L(-1)IBA and a growth period of 60 days, for the above-mentioned variables.