Nutritional diagnosis of Lippia alba (Mill) N. E. Br. grown under proportions of ammonium and nitrate and light environments

Abstract

The aim of this study was to evaluate the nutritional diagnosis of Lippia alba, cultivated with proportions of ammonium (NH₄⁺) and nitrate (NO₃^-) under light environments. The plants were subjected to five ratios of NH₄⁺:NO₃^-, through nutritive solutions, and the four light environments. The experimental design was totally randomized, with a 5 × 4 interaction and five repetitions per treatment, totaling 100 experiments. The seedlings were transplanted to 6 dm³ capacity plastic pots, containing a mixture of washed sand + vermiculite in the ratio 2:1. At 120 days after application of the treatments were evaluated the following parameters: levels of nitrogen (N), phosphorus (P) and potassium (K) in the leaves, stem, root and total (in the plant). The use of the nutritive solutions with 100% of N-NH₄⁺ and in a full sun environment resulted in higher concentrations of N in leaves, stem, roots and in the plant, as well as for the K in the roots and in the plant. The black mesh and the ratio 50:50 NH₄⁺:NO₃ ^- have significantly influenced the content of P in the stem and in the roots.