the present work was carried out with the objective to evaluate the effect of substrates in the rooting in vitro of the M-9 apple rootstock. Three substrates were tested: ágar, vermiculite (number 2, medium granulometry) and vegetal ash as physical support in the rooting of the shoots. For the treatment with vermiculite and vegetal ash, MS medium nutritive, with half of the concentration, was added in glass bottles of 250 mL with 15g of respective substrates. The shoots of 2,5 to 3,0 cm of length and two pair of leaves had been transferred to the bottles. After the inoculation the bottles were kept during 35 days in a growing chamber, at 25 ±1ºC, for a 16 hour photoperiod with light intensity of 75 µmol.m-2.s-1. The higher percentages of rooting (88,4 and 87,9%) were observed for the treatments with vermiculite and vegetal ash, respectively. The number of roots per shoot was not affected by the applied treatments. After the evaluation of the rooting, the plants were transferred to a greenhouse for 40 days, in isopor alveolated containers with 128 cells. For the survival of the acclimatized plants the best treatment was vermiculite (93,5%).
micropropagation; vermiculite; hair roots; acclimatization
