Effects of the Inoculant Strain Pseudomonas sp. SPN31 nah + and of 2-Methylnaphthalene Contamination on the Rhizosphere and Endosphere Bacterial Communities of Halimione portulacoides

Abstract

The aim of this study is to evaluate the effects of the inoculation of the saltmarsh plant (Halimione portulacoides) with Pseudomonas sp. SPN31 nah+ combined with exposure to 2-methylnaphthalene (2-MtN) on the plant rhizosphere and endosphere bacterial communities as well as on plant health. To achieve this goal, microcosm experiments were set up. Denaturing gradient gel electrophoresis (DGGE) profiles and statistical analysis showed that rhizosphere and endosphere bacterial communities had distinct responses to plant inoculation and/or exposure to 2-MtN. PCR-sequencing analysis of nah genes encoding for 2-MtN degrading enzymes suggested the presence of Pseudomonas sp. SPN31 nah+ in the endosphere of H. portulacoides with 2-MtN contamination. Moreover, a significant effect in the photosynthetic performance of inoculated plants was detected. To conclude, despite the potential beneficial effect of plant inoculation with Pseudomonas sp. SPN31 nah+ endophytic bacteria may have on plant health, no significant effect on the removal of MtN was detected for the level of contamination used in the study.

Plant-bacteria synergism: An innovative approach for the remediation of crude oil-contaminated soils

“…Additionally, cell wall-degrading enzymes favour the entrance of such microbe into plants. Endophytes have to proliferate in the rhizosphere before entering the plant (Blain et al, 2017;Oliveira et al, 2017). During endophytic colonization, bacteria move to the plant roots either inertly by soil water oscillations or actively through particular stimulation of flagella.…”