OMISSION OF CA, MG AND S IN THE FORMATION OF SEEDLING HANDROANTHUS CHYSOTRICHUS

Abstract

Yellow ipê (Handroanthus chrysotrichus) is a native forest species with great economic and ecological potential for production, conservation and forest restoration purposes. For your success in forestry plantations, different silvicultural aspects must be considered, such as soil fertility, plant nutrition and fertilization, especially in the seedling phase. The objective of this research was to evaluate the omission of Calcium (Ca), Magnesium (Mg) and Sulfur (S) in the initial growth of yellow ipê and identify the visual symptoms resulting from the lack of these macronutrients. The study was carried out at the UFCG forest nursery, Patos-PB. The design used was completely randomized (DIC), with four treatments (complete solution, omission of Ca, omission of Mg and omission of S), five replications and one plant per plot, totaling 20 plants. They were evaluated weekly, totaling 5 evaluations: plant height (cm), number of leaves and stem diameter (mm). At the end of the experiment, the aerial part phytomass (g), root system phytomass (g) and total phytomass (g) were evaluated. The number of leaves, dry mass of the aerial part, dry mass of the root and total dry mass were found to be significant, but the height and diameter of the stem were not significant at 5% significance. The greatest number of leaves and root length was observed when fertilizing without Calcium, as well as the omission of Magnesium had higher values for dry mass of the area and total dry mass. Visual symptoms were identified, with deficiencies of the macronutrients Ca, Mg and S.