Herbaceous and semi-hardwood stem cuttings of Drimys brasiliensis

Abstract

Drimys brasiliensis, known locally as cataia, is a native tree species of the Atlantic Forest. It is of phytochemical, phytotherapeutic, aromatic and economic importance, and is used, among other things, in the manufacture of liquors and condiments. It is considered to be a difficult species to multiply using seeds, as it displays dormancy due to embryo immaturity. The aim therefore was to study vegetative propagation by rooting induction of herbaceous and semi-hardwood cuttings under different concentrations of indolebutyric acid (IBA) and collected twice a year (June and December of 2011). The treatments used were: control (100% water); 0 (50% water and 50% alcohol); 1500, 3000 and 6000 mg L-1 IBA (in a 50% hydroalcoholic solution) in the winter and, in the summer, the same treatments with the exception of 0 mg L-1 IBA. One experiment was carried out using a completely randomised design in a factorial scheme of 5 concentrations × 2 types of cuttings in June, 2011; and another experiment with four concentrations × 2 collection times (cuttings from June and December, 2011). After 120 days in a greenhouse, the following were evaluated: percentage of rooted cuttings, number of roots per cutting, average root length per cutting, percentage of live cuttings, dead cuttings, those with stems, those with new shoots and those which had kept their initial leaves. The application of IBA did not influence any of the variables under study. Herbaceous cuttings showed better rooting (46.75%) compared to softwood cuttings (34.44%). Those collected in December, 2011 presented the greatest number of roots per cutting (5.47), but had higher mortality (29.05%) than those collected in June, 2011 (4.25 and 12.19% respectively). For rooting cataia, the use of herbaceous stem cuttings collected in the cold season is therefore indicated.