Efeito na indução do enraizamento em função da forma e ao tempo de preparo das miniestacas de Toona ciliata e híbridos de Eucalyptus grandis x Eucalyptus urophylla

Abstract

Clonal multiplication of plants through mini-cutting, coupled with the genetic improvement of fastgrowing forest species, has been used for productivity gains in planted forests. Thus, the objective of this work was to evaluate the relationship between the shape and time of preparation of the mini-cutting of Toona ciliata M. Roemer and hybrids of Eucalyptus grandis Hill x Eucalyptus urophylla S. T. Blake on rooting induction. Three clones of T. ciliata and three clones of E. grandis x E. urophylla, combined with two treatments, were evaluated in a separate experiment: 1) Reduction of 50% of the leaf area and; 2) Without the reduction of the leaf blade. The time spent on the preparation of mini-cuttings for each of the plots and the percentage of mini-cuttings with initial induction, rooted and with roots ≥10 cm, were evaluated every four days from the planting, and on the 28th day the dry root mass was evaluated. The preparation time of the mini-cuttings without the leaf reduction was smaller and allowed a greater efficiency in the preparation of the mini-cuttings. In addition, the management of mini-cuttings with whole leaves resulted in a reduction of the rooting time in two clones of T. ciliata, as well as an increase in the dry mass of the roots in all the clones of the two species.