Abstract

Taking into consideration that species react differently to the substrate and luminance variations, this study aimed to evaluate the leaf content of some macronutrients and dry matter in Tabebuia aurea seedlings through the hypothesis that the growth environment can alter the concentration of chemical elements in the species. The study was conducted in a greenhouse, in randomized blocks, factorial 2 × 3 (two light intensities and three types of substrates). The first greenhouse was covered with shade cloth, with maximum flow of 950 µmol m-2 s-1 radiation, and the second was 750 µmol m-2 s-1. The substrates were: 1) Cerr. Savannah soil, 2) Ca-Mg – Savannah soil with calcium carbonate and magnesium and, 3) OM – Savannah soil with organic matter (2/1), with samples taken after 230 days of experiment. The data obtained indicated that T. aurea species has better development when grown in brighter locations in OM soils, which would be expected due to its higher nutritional content. However, when the seedlings were placed in soils with low nutrient content (Ca-Mg and Cerr.) and similar levels of potassium, plants maintained in soils with higher amounts of calcium and magnesium obtained higher growth, with greater accumulation of dry matter in leaves and total. This could indicate that the difference in growth should be related to increased amount of these Ca-Mg elements of treatment and the calcicole characteristic of the species tested.

Key words: Greenhouse, seedling formation, dry matter, ipê.