Functional activity of maize roots after inoculation with growth-promoting rhizosphere bacteria Pseudomonas

摘要

We studied the role of plants in mineral nutrition in a vegetation experiment with isolated nutrition, in which the maize root system was divided into two strands, one each developing in sand and soil and inoculated separately with mixed Pseudomonas fluorescens 20 and P. putida 23 cultures. The amount of nutrients in the plant biomass increased after the inoculation, whether or not there was direct contact between the root system and the bacteria. It was demonstrated that the soil substrate has a key role in optimization of plant mineral nutrition after inoculation with the bacteria; the increased nutrient recovery by the inoculated plants was accompanied by an enhanced functional activity of the roots related to increased secretion of phenols. Introduction of indole-3-acetic acid (IAA) in the growth medium induced secretion of phenols by the maize roots. Bacterial IAA and the change in phenol metabolism (their secretion by the inoculated plants) are believed to play important roles in the realization of the influence of Pseudomonas on growth and mineral nutrition of plants.