Soil Chemical Parameters with the Use of Agricultural Gypsum and Effects on the Apple Tree Crop

Abstract

Using agricultural gypsum promotes nutrient descent and generates a less aggressive environment for roots, favoring their development and better use of water and nutrients. However, studies on apple trees are scarce, and there is no official recommendation for gypsum application in the soils of southern Brazil. This work aimed to evaluate the potential use of agricultural gypsum to increase soil fertility and apple tree productivity. The research was carried out in the municipality of Ipê, RS, in an apple orchard cv. Condessa planted fifteen years ago and with acidity in the soil layer of 20–40 cm. The design of the experiment was consisted of randomized blocks, containing five treatments and four replications, with 80 m2 each. The treatments consisted of five doses of agricultural gypsum, applied at the beginning of the productive cycle. The study evaluated soil chemical parameters at 0–20 cm and 20–40 cm, chlorophyll content, and crop productivity. The results showed an increase in the sulfur content up to the gypsum dose of 6.0 t∙ha−1 and a reduction in the magnesium content in the soil at both evaluated depths. Agricultural gypsum application did not significantly influence the other chemical parameters evaluated. Chlorophyll content in apple leaves was reduced, and there was an increase in productivity with the increase in the dose of agricultural gypsum. Therefore, gypsum can potentially improve soil fertility and increase apple tree productivity.