Humic acid and brassinosteroid on growth and nutritional status of shoots from crowns of pineapple

Abstract

The aim of this study was to evaluate the effect of brassinosteroid and humic acids on growth and nutritional status of shoots from crowns pineapple. The experimental design was randomized blocks design in factorial 5x2 scheme, five doses of brassinosteroid (BIOBRAS-16®) (0, 0.50, 0.75, 1.0 and 1.25 mg L-1) in the presence and absence of humic acid (organic soil conditioner Agrolmin®), with five replicates for each treatment. After transplanting, height, stem diameter and leaf numbers were monitored four time (0, 40, 80 and 170 days). In the last period, also were evaluated: leaf area, root volume, shoot dry matter, root dry matter, total dry matter changes and determine the levels of nitrogen, potassium, calcium and magnesium in the leaf dry matter planting. There was an effect of the treatments on planting height. The humic acid and brassinosteroid did not provide increments in leaf area, diameter, number of leaves, root volume, dry matter of shoots and roots of planting. The application of brassinosteroid reduced the content of potassium in the dry matter of the aerial part of the planting of pineapple ‘Smooth cayenne’. The supply of humic acids in the absence of brassinosteroid, elevated potassium content inpineapple plantings.