Avaliação do desenvolvimento inicial do arroz inoculado com azospirillum e cultivado em casa de vegetação

Abstract

Rice (Oryza sativa) being one of the most consumed and cultivated cereals in the world, is a crop that is present in all continents, however for its cultivation there are limiting factors for its development, one of them being nitrogen deficiency. Thus, a method that has been used is the application of bacteria known as diazotrophic bacteria that have the ability to fix atmospheric nitrogen biologically, having a high economic and environmental value. The present work aimed to evaluate the performance of Azospirillum inoculation in the initial development of rice cultivar BRSEsmeralda. The experiment was carried out in a greenhouse with 1 dm³ pots filled with dystrophic Red Latosol. A completely randomized design was used. Eight treatments with six repetitions were used, totaling 48 experimental units. The treatments used were absolute control, nitrogen treatment (50 mg dm-3 - full dose), commercial inoculant and AZ52 strain, both with and without 30% and 60% of the full N dose. The evaluations were carried out in the vegetative stage and consisted of Falker chlorophyll index, fresh and dry mass of shoots, roots and total dry mass. Sisvar software was used for data analysis and means were compared by Tukey test at 5% probability. Chlorophyll readings showed similar results among the treatments, whereas the fresh and dry mass values of roots and shoots of inoculated treatments were higher than the absolute control, while the nitrogen treatment presented the highest averages. Therefore, the inoculation with Azospirillum in the early development of rice was promising, since some of the nitrogen needed for the development of rice plants was obtained through the plant x bacterium interaction.