Sistemas hidropônicos e aplicação de reguladores de crescimento em Zantedeschia spp.

Abstract

The use of hydroponic systems and the applications of plant growth regulators are alternatives to produce and manage some ornamental species, that intend achieve high quality to the marketplace. In this study were done two studies. The aims were to evaluate the viability of two hydroponic systems and different substrates to calla lily development and to investigate the effect of flurprimidol and paclobutrazol rates in growth and development of Zantedeschia. In the first study were studied hydroponic systems as an alternative to vegetative development of calla lily. In the semi-hydroponic system the experiment was installed in a factorial design 2 x 4 (solutions x substrates). The substrates were coconut fiber, sand, vermiculite and fragments of fenolic foam. In the system Ebb and Flood, the factorial design was 2 x 3 (solutions x substrates), and the susbstrates were vermiculite, coconut fiber and expanded clay. In both systems, the nutrient solutions were the recommended to produce leaf and fruit vegetables. After 75 days, were evaluated growth characteristics. Vermiculite and sand in the semi-hydroponic system, and coconut fiber in the Ebb and Flood system promoted the best plant development, which means that both systems are recommended to produce calla lily. In the second study the aim was to investigate paclobutrazol and flurprimidol rates applied by media drench in growth response of seven Zantedeschia cultivars. It was tested five concentrations of plant growth regulators (0, 1.5, 3.0, 4.5 and 6.0 mg/pot) of two commercial products: Piccolo (fluprimidol) and Topflor (paclobutrazol). Five tubers of each cultivar were used for each treatment in a completely randomized arrangement. All cultivars responded to the rates of plant growth regulators for height control. The cultivar Santa Fe did not respond to the rates of growth regulators for floral stem height, and paclobutrazol were more effective to control this measurement. The spathe height decreased in heigher concentrations of growth regulators just for the cultivar Captain Roxy, being lower flower number observed for this cultivar as well as for the Santa Fe. Both flurprimidol and paclobutrazol can be recommended to control calla lily growth.