MINI-CUTTING TECHNIQUE FOR VEGETATIVE PROPAGATION OF Paratecoma peroba

ABSTRACT Paratecoma peroba is a native Brazilian forest species of great economic and ecological interest, which is currently at risk of extinction owing to excessive wood exploration. The use of the mini-cutting technique could facilitate the vegetatively propagation of this species. The objective of the present study was to establish a vegetative propagation protocol for P. peroba using the mini-cutting technique. In the first experiment, were tested five concentrations of indolbutiric acid (IBA; 0, 1, 2, 4 and 8 g.L-1) and two types of substrates (sand and a commercial substrate based on ground Pinus bark, coconut powder, and mineral additives). In the second experiment, were tested three types of mini-cuttings (apical of 6 cm and 10 cm, and intermediary of 4 cm) and two leaf area sizes (total leaf area and reduced to 50% of leaf area). The results showed that P. peroba could be vegetatively propagated using the mini-cutting technique with up to 82.5% rooting. There was only 5.6% of mini-cutting rooted in sand. High concentrations of IBA promotes decrease in rooting and number of roots. The 10 cm apical mini-cuttiing tend to form clones with better quality standards. The maintenance of the leaf area promotes the attainment of roots with greater root surface area, volume and dry mass of P. Peroba plants.