Agronomic performance of second crop maize and soil chemical changes after two applications of sewage sludge compost in the Cerrado

Abstract

Sewage sludge compost (SSC) is a source of organic matter and plant nutrients which can partially substitutes inorganic fertilizers and improve efficiencies of the soil chemical attributes. However, few investigations have been conducted to investigate the SSC as a micronutrients source, especially in the Cerrado region (Brazilian tropical savanna), which presents low natural fertility. The objective of this study are to evaluate the agronomic performance of the second crop maize and soil chemical changes after two applications of SSC in the Cerrado. A field experiment will be carried out in the municipality area of Selvíria, MS. The experimental design will be a randomized complete block design, arranged in a factorial scheme [4 x 2 + 2], with four replicates. The treatments of this study will consist of (I) the control treatment without any mineral fertilizers or SSC application, (II) mineral fertilizer application but no SSC addition, and (III) four doses of SSC (10.0, 15.0, 20.0 and 25.0 Mg ha-1, wet basis) applied to soil in total area and in the inter-rows. Soil samples will be collected at the end of crop harvest to evaluate the chemical changes (concentration of macro and micronutrients, OM, pH, CEC, H+Al, Al, SB, and BS). The following evaluations will be carried out in the maize plants: mineral nutrition, ICF, biometric characteristics, productive performance and the grain yield. The data set will be statistically analyzed using ANOVA, Tukey's test, correlation, and polynomial regressions.