Comportamento do Paricá (Schizolobium amazonicum Herb.) submetido à aplicação de doses de boro

Abstract

An experiment was conducted in a greenhouse in order to evaluate the effects of boron on parica growth and on concentration and contents of macro and micronutrients in dry matter of shoots and roots. Six treatments constituted by boron doses of 0.0; 0.1; 0.3; 0.9; 1.5 and 2.1 mg/dm3 in four replications were used. It was evaluated the characteristics: visual diagnostic, plants height and diameter, dry matter production of shoots and roots, concentration and contents of nutrients in dry matter of shoots and roots. The symptoms of deficiency can be observed in new leaves and roots and the toxicity in older leaves. Both boron deficiency and excess inhibits plants growth, but toxicity is more damaging. The approximate dose of 0 Estimate of average equilibrium moisture content of wood for 26 Brazilian states, by Hailwood and Harrobin one hydrate sorption theory equation.15 mg/dm3 was the best for plants growth in MSPA and MSRA. The concentration of boron increased in MSPA and MSRA with application of increasing concentration of B, with a small reduction in concentration of MSRA from the concentration 1.9 mg/dm3. The toxicity of boron begins when concentration reaches 36.06 mg/dm3 in shoots and 32.38 in roots. The contents of all nutrients, except Mn and Fe in MSPA and Cu, Fe and B in MSRA, followed its own dry matter production curves.