Forms of inoculation with promoting bacteria of growth in nutrition and agronomic performance of corn in the Cerrado

Abstract

Due to the high cost of nitrogen fertilizers and the awareness of a sustainable and less polluting agriculture, the use of diazotrophic bacteria, such as Azospirillum brasilense, has been increasing. Besides promoting a biological fixation of nitrogen, it also has phytohormonal action. Greater development of the root system, water absorption and nutrients, with positive effects on corn grain growth and yield. In addition to Azospirillum brasilense there are other plant growth promoting bacteria, such as Pseudomonas fluorescens, Bacillus subtilis, Bacillus pumilus, Bacillus licheniformis and Bacillus amyloliquefacens, which have been tested, as well as to define a better inoculation method in the corn crop. Information on the effect of inoculation with these microorganisms. The objective of this research was to evaluate the effect of the inoculation of seed of corn crop and safrinha, with six different species of plant growth promoting bacteria, applied via seeds or in a directed jet at the base of the plant, always with 25% reduction in dose De N, on a concentration of foliar nutrients, production components and grain yield in the Cerrado region, as well as analyzes of greenhouse gases and soil in the arable layer. The experiments were carried out in Selvíria - MS, in a Dystrophic Red Latosol in a direct plane system with a spacing of 0.45 m between rows. The experimental design in the two corn crops will be in randomized blocks with four replicates, arranged in a 6 x 2 + 3 factorial scheme, six inoculations with species of plant growth promoting bacteria (A. brasilense, B. amyloliquefacens, B , B. pumilus, B. subtilis and P. fluorescens), applied via seed or directed spray at the base of the non-stage plant, in all treatments with a 25% reduction in the N dose recommended in coverage; Besides the control without inoculation and nitrogen fertilization; Fertilization with a recommended N dose (150 kg ha-1 = 100%) under cover and without inoculation; And application of 75% of the dose of N (112.5 kg ha-1) recommended in coverage and without inoculation. Will be found: the index of foliar chlorophyll (ICF); Concentrations of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn in the diagnostic sheet; Plant height and spike insertion; Production components; Grain productivity; Accumulation of nutrients in the dry matter of the aerial part at the end of the cycle and in the grains; Soil chemical attributes in the 0 to 0.20 m layer after maize cultivation. (AU)