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Seedling production of canjerana (Cabralea canjerana (Vell.) Martius) has been limited by difficulty in germination, caused by recalcitrant behavior of their seeds. The objective of this study was to develop an efficient protocol for conservation and production of canjerana micropropagated plantlets. Seeds of canjerana were disinfected with 0, 2.5, 5.0, 7.5 and 10% of NaOCl solution, at immersion times of 10, 20 and 30 min to produce aseptic seedlings, which were cultivated on Murashige and Skoog (MS) and Woody Plant Medium (WPM) media. Nodal segments were cultivated in WPM medium supplemented with 0 and 2.5 µM of 6-benzylamine purine (BAP), kinetin (KIN) and thidiazuron (TDZ) or with 0, 1, 3, 6, 9 and 12 µM of BAP. Micro-cuttings were cultivated in MS and WPM media with 0 and 5.0 µM of indole-3-butyric acid (IBA) and naphthaleneacetic acid (NAA). The rooted micro-cuttings were acclimatized in a humid chamber in a greenhouse. The highest percentage of aseptic seedlings was produced with a solution of 7.5% of NaOCl and immersion times of 20 and 30 min. Adding BAP, KIN and TDZ or increasing concentrations of BAP to the WPM medium did not increase shoot number and length. Neither the base medium nor the auxin (IBA and NAA) had a significant effect on the survival of micro-cuttings after 60 days of cultivation, but the addition of 5.0 µM of NAA did increase the percentage of rooting and survival during the acclimatization. Both nodal segments and micro-stumps of canjerana have showed a low rate of multiplication. The addition of 5.0 µM of NAA to the basal medium increased the percentage of in vitro rooting and the percentage of survival during acclimatization of canjerana plantlets. Key words: In vitro propagation, in vitro multiplication, in vitro rooting, acclimatization, microclonal hedge.

Canjerana (Cabralea canjerana (Vell.) Martius) is a tree species indigenous to Brazil that when grown and managed in plantation systems are of great ecological and economic importance. Due to the difficulty of producing seminal seedlings, we examine the possibility of vegetative propagation by evaluating the rooting potential of canjerana mini-cuttings with different concentrations of indolbutyric acid (IBA) and substrate combinations. Mini-cuttings were treated with 2000 mg/L of IBA and planted in commercial substrate; coarse sand; carbonized rice husks; and a combination of the two. Apical and nodal mini-cuttings were treated with 0, 1000, 2000 and 3000 mg/L of IBA and planted in a combination of commercial substrate, coarse sand and carbonized rice husks. A mini-clonal hedge was formed with three clones of canjerana to evaluate mini-stump productivity and mini-cutting rooting. The combination of commercial substrate, coarse sand and carbonized rice husks maximized mini-cuttings rooting. Nodal mini-cuttings had higher rooting capability than apical ones. The application of 3000 mg/L of IBA improved rooting differentiation and growth of canjerana mini-cuttings. Canjerana clones differ in rooting capability and survival rates in vegetative propagation systems, but the use of a mini-cutting propagation system is a feasible production technique for this important species. Key words: Vegetative propagation, miniclonal hedge, mini-cutting rooting, indolbutyric acid.