Efeito da adubação nitrogenada e fosfatada no desenvolvimento, atividade antioxidante e teor de fenóis, taninos condensados e flavonóides de Hemerocallis fulva

Abstract

Hemerocallis is one of the most important genders of ornamental evergreen herbaceous, some species are used in cuisine and popular medicine, but information about fertilization is still small frequent to this specie. This way, this work has as aim to evaluate the effect of nitrogen and phosphorus rates on growth, development, flowering, antioxidant activity, content of phenolics, condensed tannins and flavonoids of Hemerocallis fulva specie. The experiment was carried out in two stages, which one of those was the field stage at Gardening area and other one in the laboratory stage in the Plant Medicinal Laboratory and Soil Fertility Laboratory of the Faculty of Agrarian Science of the Federal University of Grande Dourados – MS. Used experimental design was randomized blocks with 25 treatments that were arranged as 5 x 5 (nitrogen and phosphorus rates) factorial scheme with four replications. As N source, urea was used (45% of N), and P source, triple superphosphate. Studied rates were: 0; 75; 150; 225 and 300 kg ha-1 of N and 0; 100; 200; 300 and 400 kg ha-1 of P. Used variety was ‘flore Pleno’ H. fulva, grown in plots. Different rates of phosphorus and nitrogen have effect on growth and development of H. fulva and on the content of N and P extracted from leaves and roots. The highest tillering of plants did not increase the number of flowers per plant. Rates of 100 kg ha-1 of P promoted higher flowering production and higher flowering stage. The increase of sprouting of flower scape did not increase the number of flower per plants and plants with the smallest number of tiller produce more flowers. Contents of phenolics, flavonoids and condensed tannins of H. fulva are not altered by nitrogen and phosphorus fertilization. Roots of H. fulva, independent on nitrogen, phosphorus or other fertilization, had antioxidant activity Potential.