Casearia sylvestris Swartz (Salicaceae), or "guaçatonga", is a tree native to Mexico and Central and South America, with great ecological, pharmacological and commercial relevance. Similarly to most native species of medicinal interest in Brazil, "guaçatonga" is not commercially cultivated and is obtained by means of extraction. The aim of this study was to test a protocol for the vegetative propagation of "guaçatonga" by means of stem cutting, identifying the best season for stem rooting and assessing the effect of using the growth regulator indolebutyric acid (IBA). In the fall, winter and spring 2007 and summer 2008, semi-hardwood cuttings with 12-14 cm length and two leaves were prepared and treated with IBA (0, 1000, 2000 and 3000 mg L-1), in alcohol solution, by rapidly immersing for 10 seconds the base of cuttings and planting them in tubes containing Plantmax HT® in greenhouse under intermittent nebulization. Experimental design was completely randomized with 4 replicates, 4 treatments and 16 cuttings per plot. All experiments were evaluated after 90 days, and for two of them the time of maintenance in greenhouse was prolonged in order to improve root development. The following parameters were evaluated: percentage of rooted cuttings, percentage of live cuttings (with callus and without roots, without callus and without roots), percentage of retained leaves, percentage of dead cuttings, number of roots, length of the largest roots (cm) and mean dry mass of roots (mg). There was no rooting on cuttings collected during the fall and the winter. For cuttings collected in the spring, 39.1% rooting was obtained. Cuttings collected in the summer did not show the expected results, presenting after 240 days 6.3% rooting when treated with 3000 mg L-1 IBA. Up to 3000 mg L-1, IBA did not stimulate the rooting of "guaçatonga" cuttings and the best season for cutting is spring.
Casearia sylvestris Swartz; rooting; auxin; seasonality
