Methods of application of indolebutyric acid and basal lesion on 'Woodard' blueberry cuttings in different seasons

Blueberry cuttings are difficult to root, so alternatives that maximize their rhizogenic potential are essential for the expansion of the crop. The objective of this work was to evaluate the effect of the basal lesion and different methods of indolebutyric acid (IBA) on the rooting of 'Woodard' herbaceous cuttings, collected in two seasons. The experimental design used was completely randomized in a 3x2x2 factorial arrangement, totaling 12 treatments and five replications. The factors consisted of different ways of IBA application (talc and alcohol in the concentration of 1,000 mg L-1, and without IBA), season of collection (autumn and summer), and two types of cuttings (with and without lesion in the basal portion). Two hundred days after the beginning of the experiment, there was no significant effect of the basal lesion on the rooting of the cuttings. However, it was found that rooting is influenced by the season of collection, with greater leaf retention, dry weight, number of roots per cutting, length of roots and length of the largest root collected in summer. The application of IBA talc provided a higher percentage of rooted cuttings (61.0%) in relation to alcohol (31.0%) and control (41.0%) when collected in the autumn. There was no difference between seasons when IBA was applied with talc, however, the application with alcohol solution and the control resulted in higher percentages of rooted cuttings in the summer (70.0% and 67.0%, respectively). Summer was considered the best season to collect `Woodard' blueberry cuttings, although the IBA applied with talc has increased the percentage of rooted cuttings in the autumn. The basal lesion did not promote an increase in rooting.