Application of plant growth promoting microorganisms in soybean cultivation

Abstract

The application of microorganisms that promote plant growth through inoculation favors mineral nutrition, increasing the availability of nutrients, thus increasing the production of soybeans. The objective overall was to evaluate the application of doses of plant growth promoting microorganisms, Bradyrhizobium japonicum, Azospirillum brasilense and Pseudomonas fluorescens, in soybean crop production. The experiment with soybeans in the direct seeding system was carried out in the district of Minga Guazú, department of Alto Paraná, from October 2016 to February 2017, using a randomized complete block design, with seven treatments and four repetitions. The applied doses of the inoculant were: 0, 75, 150, 225, 300, 375 and 450 ml ha-1. The inoculant was applied to the seeds at the time of sowing. In the phenological development stage R5, R6 and R7, plant height, aerial dry mass production, root dry mass production, number of nodes, number of root nodules, number of pods, number of grains per pod were evaluated and distribution of number of grains per pod; mass of thousand seeds and grain yield. Analysis of variance, comparison of means by Tukey’s test at 5% probability of error and regression analysis were performed. The variables analyzed in the soybean crop did not show a significant effect on inoculation, except for grain yield, which obtained a significant response, reaching a maximum value of 5036 kg ha-1 with a dose of 140 ml ha-1. The application of inoculants increases the production of soybeans.