The objective was to study the growth, biomass allocation and concentration of nutrients in Heteranthera reniformis Ruiz & Pav. under the effect of different concentrations of Ca, Mg and S. The plants were cultivated in plastic pots fulfilled with rolled stone, in nutrient solutions of 80% of the original concentration of Sarruge. The experiment was carried out in a complete randomized design, with 4 contents (0, 25, 50 and 75% of the base solution) evaluated in Ca, Mg and S, plus the control (100% of the solution base), with 4 replicates in the period of 35 days in greenhouse. The increase of contents of Ca produced significant reduction in the leaf. The largest areas leaf occurred in solutions of 25% of Ca and 50% of Mg and S. The largest proportion of dry biomass was found in the stem, except with 25% of Ca (40 mg.L-1) in solution that produced larger leaf area and larger specific leaf area. Among different Mg contents, larger biomasses were observed at 50% of Mg (19, 2 mg.L-1) and, for S, there were not significant differences, except at 0% of S in solution. The solution with 160 mg.L-1 of Ca produced the largest concentration of Ca in leaf (56, 6 g.kg-1). The contents of Ca, Mg and S in solution corresponded to a proportional increase in the plant. The contents of sulfur in leaves and in stems increased with the concentration of S, whereas the content in roots reduced in the concentrations between 12,8 and 38,4 mg.L-1.
Aquatic plant; weed; nutrients and biomass
