Desempenho agronômico de cultivares de arroz irrigado sob doses de fertilizante de liberação controlada

Abstract

As crop productivity increases, the nutrient requirement also increases. However, the low efficiency of fertilizer use is a major problem widely discussed and studied over the years. Considering that the use of coated fertilizers can provide lower losses and greater availability of nutrients in the soil, this study aimed to evaluate the agronomic performance of irrigated rice genotypes submitted to doses of controlled release fertilizer under irrigated floodplain conditions in the municipality of Formoso do Araguaia, southwest region of Tocantins State. The experiment was carried out in January 2018. Seeding was done in a commercial area, in a randomized block design, with four replications, in a factorial scheme (6 x 6) + 1. The factors were six cultivars of irrigated rice (BRS Catiana, BRS Pampeira, BRS Tropical, Lexus CL, XP 113 and XP 115), six doses of controlled release fertilizer (0, 150, 300, 450, 600 and 750 kg/ha) and one control, for each cultivar, that received conventional fertilizer application. The evaluated parameters were: number of panicles per m², number of grains per panicle, percentage of sterile grain and productivity. The genotype XP113 showed the highest productivity under the evaluated conditions, while the BRS Tropical was the lowest productive genotype. There was no significant difference between the controlled release fertilizer and the conventional fertilizer, due to late sowing. There was a difference among the irrigated rice genotypes about the efficiency of nutrient absorption.