Biofertilizante de rochas mais matéria orgânica inoculada com bactéria diazotrófica na cana-de-açúcar

Abstract

Sugarcane (Saccharum spp.) Is currently considered one of the most important crops in the Brazilian social and economic. In Pernambuco, the sugar cane industry occupies an important agricultural area with high sugar and ethanol, generating many direct and indirect jobs. For increased productivity becomes necessary the use of management technologies that foster the development of culture. Currently, the productivity of plants has been basically ensured by the use of mineral fertilizers soluble, which may result in environmental risk and high production cost. It has been common in plants using sugarcane filter cake as a way to increase the nutrition of plants, and consequently the yield. However, an alternative to replacement of the NPK fertilizer mixture is soluble commercial rock biofertilizer with addition of elemental sulfur Acidithiobacillus inoculated with the bacteria in admixture with organic matter inoculated with free-living bacteria diazotrophic NFB 10001. The objective of this study was to evaluate, against the commercial soluble fertilizer (NPK) and by whether or not the filter cake, the effect of biofertilizer mixed (BNPK), production and technological characteristics of sugar cane, as well as evaluation of the input chemical characteristics of soil. The experiment was a randomized block design with four replications. The survey was conducted in an area belonging to the Usina Santa Teresa, located in the city of Goiás, forest area north of the state of Pernambuco in the geographical coordinates 07 º 33 'S and 35 º 00' W and altitude of 13 m. It was cultivated variety RB 92579 sugarcane ajacentes in two areas, one with and one without filter cake on the foundation. The rock biofertilizer (BPK) is produced by mixing parts of apatite and biotite in the presence of Acidithiobacillus and sulfur, while the production of biofertilizer mixture was made by mixing BNPK worm humus and inoculated with free living diazotrophic 1:3 ratio, respectively. The mixture of the soluble fertilizer (FNPK) was performed using ammonium sulfate (20% N), single superphosphate (20% P2O5) and anhydrous potassium (60% K2O), according to the analysis of soil and the recommendation for the culture . The application of filter cake, in general, positive influence on plant height, stem diameter, shoot dry matter, yield and technological characteristics of sugar cane, and the BNPK in larger doses presented the best results, the BNPK showed results similar to commercial fertilizer in supplying soluble N, P, K, Ca and Mg of sugarcane having its effect enhanced by the application of filter cake on the foundation, the BNPK was equivalent to commercial fertilizer in the supply of N, P and K the soil, but also demonstrated a greater ability to supply Ca and Mg, and the filter cake helped to increase these nutrients in the soil in all treatments.