Atividade microbiana e fósforo disponível no solo com cana soca após adubação fosfatada e torta de filtro na cana planta

Abstract

Phosphorus fertilization on sugarcane has received much research attention in recent years. The use of different phosphate sources with varying source and solubility has required studies to prove the efficiency of phosphorus supply to reduce environmental and economic losses. The organic fertilization with the filter cake is presented as routine practice in the mills, partially replacing phosphorus with gains in productivity. This study aimed to evaluate sources of phosphates (superphosphate and reactive phosphate) fertilizer in the sugarcane plant and its residual effects in the production of ratoon, as well as to evaluate the effect of the filter cake associated with these sources of phosphates. For were quantified this biological parameters related to the P cycle in soil and yield components of sugarcane. O experiment was installed in March 2011 in Presidente Prudente-SP. The experimental design was a randomized complete block design with four replications in a split plot design, with portions formed by superphosphate application (SS) Reactive Phosphate Arad with different proportions between SS with FRA. The subplots consisted of the presence or absence of filter cake in the furrow. There was no change in the growth and yield of the crop when it employed the different associations of phosphate fertilizers, with or without filter cake, yet treatment with soluble phosphate decreased ratoon cane yield when compared with the yield of the sugarcane plant. The only soluble phosphate fertilizer source had higher levels of phosphorus in soil and microbial biomass. The filter cake application was beneficial to increase the biomass, microbial, phosphorus and the soluble phosphorus in the soil, but also similarly maintained the performance of cane two years evaluated.