PARÂMETROS NUTRICIONAIS DA CANA-DE-AÇÚCAR CULTIVADA COM CARBONATITO FOSFÁTICO E MICRORGANISMOS BIOSSOLUBILIZADORES DE FÓSFORO

Abstract

Brazil's dependence on imported fertilizers and the low availability of phosphorus in tropi-cal soils intensify the search for sustainable alternatives for crop nutrition. The objective was to evaluate the nutritional status of sugarcane subjected to different phosphorus sources associated with biosolubilizing microorganisms. The experiment was carried out in a green-house, in a randomized block design with four replications. Three phosphorus sources were evaluated (phosphate carbonatite rock powder, single superphosphate, and a combination of both) associated with inoculation/co-inoculation of Bacillus spp., Cladosporium cladospori-oides, and Trichoderma harzianum. Ninety-five days after planting, foliar macro- and mi-cronutrient levels were determined. The results showed that the use of the remineralizer provided phosphorus levels like soluble fertilizer, in addition to contributing to potassium supply. The combination of sources favored an increase in zinc. Regarding microorganisms, Trichoderma harzianum stood out by promoting increases in phosphorus, sulfur, and micro-nutrients, regardless of the source used, while Bacillus spp. and Cladosporium cladospori-oides showed greater efficiency when associated with poorly soluble sources. It is concluded that the use of remineralizers associated with biosolubilizing microorganisms constitutes a promising strategy to increase the nutritional efficiency of sugarcane, reduce dependence on imported fertilizers, and promote sustainable production systems.