Tecnologias para fertilizantes organominerais na sucessão soja milho

Abstract

Phosphate fertilizers are extensively employed in global agriculture, and phosphate rocks are considered a limited resource, potentially subject to scarcity. Phosphorus (P) presents a complex dynamic in acidic soils, being readily adsorbed, resulting in the loss of significant amounts of this nutrient, which cannot be used by plants. The presence of organic matter exhibits a direct and indirect relationship with phosphorus, which can reduce its adsorption in soils and improve the efficiency of nutrient use. The associated use of organic matter with mineral fertilizers generates organomineral fertilizers, which can be used as an alternative source for conventional mineral fertilization, mainly in cerrado soils, seeking to promote better results in the use of P and enrichment of the soil's microbial community. . The present study aimed to evaluate the agronomic efficiency of mineral and organomineral fertilizers on soybean and corn yield as well as changes in chemical and biological attributes of the soil. The experiment was carried out in the city of Luminárias/Mg under field conditions for two harvests, 6 treatments were applied using OM18, OM30, OM18+Bacillus, OM30+Bacillus, MAP and SS, all treatments in increasing doses (40 , 70, 100, kg P2O5 ha-1 for soybeans) and (32, 56 and 80 kg P2O5 ha-1 for corn), five collections of plants were carried out to evaluate the nutritional status, V4, V7, R2, R5 and R8 in soybeans, and V7,V14,R2,R4 and R6 in corn. Release tests were carried out together to determine the fertilizer release curve in the field and in the laboratory. With this, grain yield and total dry mass of crops, nutrient export, P accumulation, absorption rate and the activity of the enzymes arylsulfatase, b-glucosidase and acid phosphatase were evaluated. For the agronomic efficiency and phosphorus recovery indices, there was no statistical difference between the doses and sources applied. Regarding accumulation, a statistical difference was observed with increasing doses, reaching maximum accumulation at the highest dose of P2O5 for both soybeans and corn. Productivity showed no statistical difference for doses or sources in soybean cultivation, and in corn, only the control treatment differed from the others in corn cultivation. In relation to enzymatic activity, there was no influence of mineral and organomineral fertilizers on the enzymatic activity of the soil. As for reducing doses, conventional mineral and organomineral treatments showed similar responses, suggesting that, in soils with constructed fertility, reducing doses in a single harvest does not change the productive parameters for both sources tested. In general, both organominerals and conventional fertilizers presented similar phytotechnical and productive results. It is concluded that, when compared, organomineral fertilizers present themselves as an alternative or complementary technology to conventional mineral fertilizers, when applied in equivalent doses.