Azospirillum brasilense em capim-marandu associada ou não ao nitrogênio

Abstract

Due to economic and environmental cost resulting from the use of nitrogen fertilization, an alternative has been sought that can guarantee a reduction in the use of fertilizers without reducing production yield. One of the alternatives found is the use of bacteria of the genus Azospirilum, free-living microorganisms that fix atmospheric nitrogen and live associated With plants in the rhizosphere. One of the advantages of this process is both development and increase in biomass production. The research aimed to evaluate the effects of inoculant based on Azospirilum Brasilense associated or not with nitrogen fertilization on marandu (grass. The design used was randomized blocks, with five fertilization strategies, with six replications. The fertilization strategies consisted of 30 L ha-1 month-1 of A. Brasilense (30Az); 30 L ha-1 month-1 of A. Brasilense vith nitrogen fertilization (30A2N); 6O L ha? month" of A. Brasilense (60Az); 60 L ha-1 month-1 of A. Brasilense with nitrogen fertilization (60AzN); and the control treatment only with nitrogen fertilization (SAzN). Univariate analysis showed that inoculation of A. Brasilense associated or not with nitrogen fertilization offers increments in structural and productive characteristics, while there was no significant difference for bromatological characteristics. Multivariate analysis showed that the control treatment was 3 functional groups different from the others, demonstrating that the treatment with Azospirilum is efficient compared to the treatment without the use of A. Brasilense solution for structural and productive characteristics. For bromatological characteristics, it is observed higher efficiency in treatments with A. Brasilense dosages with or without nitrogen.