Avaliação de fertilizante organomineral fosfatado produzido com cama de frango e das perdas de fósforo em solo do Oeste da Bahia

Abstract

Organomineral fertilizers can supply part of the nutrient demand to crops and ensure better management of agricultural wastes. This work aimed to evaluate the agronomic performance and the losses of P by erosion under field conditions and to determine the agronomic and P recovery efficiency in pot experiments, of a phosphate organomineral fertilizer (OMF) produced with chicken litter and monoammonium phosphate (MAP). In greenhouse, four successive maize crops were carried out in pots with 10 kg of two Latossols, one of sand texture and other with clay loam. MAP and OMF were evaluated under five levels of P applied (0, 50, 100, 200 and 400 mg kg-1). The phytomass and P accumulation, the agronomic and fertilizer recovery efficiency, and soil available P were determined. Levels of available P were higher with MAP in sand soil, without differences between fertilizers in the clay loam soil. The OMF promoted higher maize dry matter and agronomic efficiency in the first crop. The accumulation of P and P recovery efficiency did not differ among fertilizers. In the field experiment, OMF, MAP, single superphosphate (SSP) were evaluated at 0, 40, 80 and 160 kg ha-1 levels of applied P2O5, with surface-broadcasted fertilization or localized fertilization in the furrow, in a Yellow Latosol of sandy loam texture, in the municipality of Luis Eduardo Magalhães, State of Bahia, in corn and soybean crops in succession. The accumulation of phytomass and P in shoots, grain yield, accumulation of P in grains and soil available P were evaluated. In each plot, galvanized steel sheets were drilled in the soil to delimit an area of 3 m² for evaluating soil and P losses due to surface erosion. In corn cultivation, localized fertilization promoted greater grain yield, phytomass accumulation and P accumulation in shoots, than surface-broadcasted fertilization. MAP provided greater accumulation of P in corn grains. Increased applied levels of P as OMF and MAP resulted in greater accumulation of P in corn grains in surface-broadcasted fertilization. In soybean cultivation there was no effect of sources, levels and forms of application on grain yield, P and N accumulations in grains and phytomass accumulation. The FOM and MAP promoted greater accumulations of P and N in the soybean phytomass as compared to SSP. The surface-broadcasted fertilization promoted higher levels of soil available P after corn cultivation, while after soybean cultivation, localized fertilization conferred higher levels. The surface-broadcasted fertilization promoted higher P losses due to erosion. The performance of OMF was similar to mineral fertilizers, which indicates good potential of using chicken litter in organomineral formulations.