Rooting and survival of cork oak cuttings

I Congresso Luso-Brasileiro de HorticulturaThe cork oak (Quercus suber L.) has remarkable ecological, social and economic value in the Mediterranean region. Due to the growing economic interest in cork, human intervention in the plant production and renewal of this species is crucial. Thus, the optimization of the propagation methodologies to produce selected and improved trees for high quality cork production is a key factor in the species improvement program. Rooting and survival of cuttings are greatly affected by several external and internal factors. To circumvent this problem, experiments were made using young seedlings as a source of cork oak cuttings for two consecutive years. We studied the influence of the application of synthetic auxins, indole-3-butyric acid (IBA) and α-naphthalene acetic acid (NAA), the IBA concentration and the basal bark removal in rooting and survival of cork oak cuttings. The IBA improved the rooting, the survival and the mean length of the longest root per rooted cutting, but not the mean number of primary roots produced. The basal bark removal associated with 0.5% of IBA gave the highest percent of rooting and plant survival (60% and 54%, respectively). The application of 0.1% of NAA had no significant influence on the rooting and survival. Thus, it is possible to draw the conclusion that wounding along with 0.5 % IBA produced the highest percentage of rooting and survival with cuttings planted in April, however complementary studies involving different physical and chemical conditions are required