PROPAGATION OF THE Nerium oleander Linn. BY THE AIR-LAYERING TECHNIQUE IN DIFFERENT SUBSTRATUM

Abstract

The vegetative propagation of ornamental plants is generally made by the cutting technique. However, this reproductive process not always presents satisfactory results, especially at times of the year when the plant lives an intensive vegetative development, this way affecting, its comercial production. Air-layering is another largely used technique. The necessary information for this practice is rare and inconsistent. So, it is indispensable to adapt an analitic and explanatory approach. Nowadays, the air-layering in ornamental plants has been represented as a propagation method that supplies a good rooting and many times, without the necessity of a phytoregulators application. This paper tried to avaluate the efficiency of the air-layering process related to the rooting of the Nerium oleander, in three different substratum (Dicksonia sellowiana [tree fern] sow dust, vermiculite, and organic soil). The experiment was installed at Campus III, Technological Center of the Universidade Federal of Paraná, in Curitiba city, in the equinox of the year 2000, where the complete ringing technique was used in semi-woody branches of adult plants of Nerium oleander. It was used completely randomized delineation and the data submieted to the variance analysis, by the Tukey Test to a level of 1% of statistic probability. Each treatment consisted of four replications, analysed after 63 days of the installation of the experiment. It was conclued that the air-layering practice promoted enough rooting in all substratum, and the organic soil the one that supplied the most development of the roots.