Água ferrosa no cultivo de girassol ornamental em vasos irrigados por gotejamento

Abstract

The objective of the present study was to determine the critical concentration of iron in irrigation water that interferes with the performance of the ornamental sunflower, 'Sunflower F1 Sunbright Supreme' cultivar produced in pots and subject to drip irrigation. A 4 × 2 completely randomized factorial design was adapted with four replications, testing four iron concentrations in water (0.0, 0.5, 1.5, and 3.0 mg L-1) and two types of emitters (selfcompensating and conventional). The experiment was conducted in a greenhouse and the following characteristics were evaluated: shoot height, stem and root system length, stem diameter, number of leaves, leaf area, shoot dry weight, root dry weight, flower dry weight, total dry weight and flower diameter. The use of water with the presence of iron did not produce satisfactory results compared to the commercial standards of ornamental sunflower production, precluding its use under irrigation conditions.