Morphophysiological characteristics of maize inoculated with Azospirillum brasilense and Herbaspirillum seropedicae as seed treatment, cultivated in different types of soil

Abstract

This work aimed to evaluate the morphological characteristics of maize inoculated with Azospirillum brasilense (AbV5) and Herbaspirillum seropedicae (SmR1) by seeds treatment, grown in four different types of soil from the Western region of Parana. The experiment was conducted in a greenhouse at State University of Western Parana. The used experimental design was a randomized block, in factorial scheme 4x4, with four replications. The first factor is related to the bacteria, with the treatments: without inoculation; AbV5, A. brasilense; SmR1, H. seropedicae; mix with the two strains. The used soils were from the horizon A, ranked as Dystric Acrisol, Eutric Umbrisol, Eutric Ferralsol and a Eutric Acrisol. The experiment was conducted until the 30 days after emergence (DAE), when plants were collected for the following biometric evaluations: leaf area, root volume and dry mass of culm, leafs and root, calculus of the total dry mass and the quotient between root system and shoot system mass. After, root volume, root density, relative level of chlorophyll in leafs, by SPAD and level of protein in leafs was determined. No significant effect was found from the inoculation of the strains AbV5 and SmR1 for the biometric and biochemical variables evaluated for the ‘hybrid corn DKB 390’, grown until 30 DAE. The corn plants showed lesser development when cultivated in land from the horizon A of the Eutric Umbrisol. More studies are necessary with the objective of investigating the existing relations between the strains of biological nitrogen fixation (BNF) and genotypes of corn, seeking to decrease the necessity of nitrogen fertilization in corn culture. Key words: Nitrogen, Zea mays L. biological fixation of nitrogen, soil.