Desenvolvimento de estacas de crajiru (Arrabidaea chica Verlot.) em função do diâmetro da estaca e do ambiente de cultivo.

Abstract

The goal of this work was to observe the effects of two growth environments on two types of crajiru (Arrabidaea chica Verlot., family Bignoniaceae) as a function of cutting diameter ultimately to establish the better type of crajiru (type 1 or 2) for propagation from cuttings. The experiment was conducted using an entirely randomized method with a 2 x 2 x 4 factorial scheme, with 6 repetitions, 2 root development environments (1 – substrate and 2 – water) and 4 average basal cutting diameters: 1.1, 0.6, 0.4 and 0.2 cm, designated woody, semi-woody, herbaceous and apical stems, respectively. The cuttings were approximately 15 cm in length having leaves only on apical cuttings and 5 cuttings per repetition. The substrate was prepared from area : argila : humus (3 : 1 : 1). Each cutting was placed in an individual poliethylene bag of 1 kg capacity. For cuttings in liquid environment, 2 L polyethylene terephthalate bottles (PET) containing approximately 500 mL of water were used. From the start of the experiment, the cuttings were maintained in an environment covered with transparent plastic roofing and received daily irrigation. After 90 days, the following variables were evaluated: % established cuttings, average length of new growth (cm), average length of roots (cm) dry mass of leaves and roots (g / plant). After variance analysis, the averages were compared using the Tukey test and a 1 % probability. Crajirú responded well to vegetative regeneration from cuttings and the type 2 variety developed better in general than type 1. The percentage of established plants was greater in the substrate 1 (soil) for cuttings of average diameter 1.1 cm. Other variables were also superior for this diameter cutting, and the substrate was responsible for the nutirition of these cuttings, which presented better development in those of 1.1 cm diameter. Since the difference between the development in both environments (substrate vc. Water) was small, and the interaction treatment x environment x diameter was not significant, one can site an economical advantage using water for the preparation of crajirú plants from cuttings.