Rendimento em milho inoculado com azospirrillum brasilense associada ou não à adubação nitrogenada

Abstract

Bacteria of the Azospirillum brasilense genus are atmospheric nitrogen (N) fixers and are considered plant growth promoters. Therefore, this study was developed with the aim of evaluating the yield of Pioneer brand corn, in response to the inoculation of Azospirillum brasilense associated or not with nitrogen fertilization. The experiment was conducted in a randomized block design (RBD). Five treatments were tested with four repetitions, totaling 20 experimental units. The following treatments were tested: T1 = without fertilization; T2 = fertilization in the sowing furrow, without nitrogen fertilization in coverage; T3 = fertilization in the furrow with nitrogen fertilization in coverage at stages V4 and V8; T4 = fertilization in the furrow, without nitrogen fertilization in coverage + Azospirillum brasilense; and T5 = fertilization in the furrow + nitrogen fertilization in coverage at stages V4 and V8 + Azospirillum brasilense. The variables analyzed in the experiment were: plant density/m2, number of ears/m2, number of grains per ear, mass of a thousand grains and grain yield equivalent to kg/ha-1. Nitrogen topdressing associated with furrow fertilization favored the development increase of crop productivity, presenting an increment of 1,615.5 kg more production, equivalent to 25%, when compared to the treatment that only used fertilization in the furrow. The combined inoculation of the strain provided an increase in production of 2,539.5 kg.ha-1, an increase of 31% in productivity compared to the treatment that received only nitrogen topdressing associated with furrow fertilization, indicating benefits of the combination of diazotrophic bacteria that interact differently with the plant.