Total and diazotrophic bacteria in the soil, rizoplane and endorizophere of plants under different soil management systems

Abstract

The total microbial and diazotrophic comunity were evaluated in areas with no-tillage system (SPD) and conventional planting system (SPC) in Cruz Alta - RS. Diazotrophic population assessments were carried out in four different soil depths, in the rhizoplane and endorizosphere of the rotations crops: wheat / soybean (R1) and wheat / soybean, black oat / soybean, vetch + black oat / corn (R2). The collections were made in both systems and in two rotations and in two seasons (winter and summer). Planting systems do not influence the population of diazotrophic bacteria in the soil. The diazotrophic population was influenced by the rhizospheric environment, with a predominance of non-rhizoplane diazotrophics in relation to the endorizosphere in the studied rotations, except for the wheat crop. As crop rotations occur as sources of total crops in corn, with a larger population without SPD, without rhizoplane and endorizosphere.