Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background and aims</jats:title> <jats:p>Recent research has recognized the presence of metal-resistant bacteria in plants and their role in phytoremediation intensification. However, information on the antibiotic resistance profile of those bacteria remains scarce. This study, describes the first isolation of endophytic bacteria from green parts of <jats:italic>Armeria maritima</jats:italic> growing on mine-tailing soil in southern Poland, and presents the resistance profile of these microorganisms.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Bacteria were isolated from internal tissues of <jats:italic>Armeria maritima</jats:italic> and characterized. Minimal Inhibitory Concentration (MIC) of metals was determined by the plate dilution method using (CH<jats:sub>3</jats:sub>COO)<jats:sub>2</jats:sub>Pb and ZnSO<jats:sub>4</jats:sub> supplemented medium; antibiotic susceptibility was determined by disk diffusion method according to EUCAST version 11.0; the whole genome sequencing was performed using the MiSeq platform (Illumina). The physicochemical properties of soil were evaluated according to European Standards.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Toxic metal-resistant bacteria were isolated from the green parts of <jats:italic>Armeria maritima</jats:italic>. The endophytes were identified as <jats:italic>Pseudomonas</jats:italic> spp. The annotated bacterial genomes carried genes encoding numerous metal ion transporters, metal reducing enzymes and efflux pump components. The bacteria were resistant to streptomycin, fosfomycin and ß-lactams. Moreover, genome analysis revealed the presence of MacAB-TolC efflux pump genes conferring resistance to macrolides, the multidrug efflux pumps AcrAB-TolC and MexAB-OprM.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p><jats:italic>Armeria maritima</jats:italic> is inhabited by endophytic bacteria identified as <jats:italic>Pseudomonas</jats:italic> species that are resistant to metals and to antibiotics. Under the One Health concept the contamination of soil and plants with ARB and ARGs should be monitored and limited and a regulatory framework for safety use of bacterial bioinoculants should be established.</jats:p> </jats:sec>

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Aims</jats:title> <jats:p>To assess the symbiotic effectiveness, tolerance to abiotic stress factors and phosphate solubilizing ability of new chickpea root-nodule bacteria.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Symbiotic effectiveness, abiotic stress tolerance and phosphate solubilizing ability of ten new chickpea rhizobial strains collected from soils were evaluated using laboratory and glasshouse experiments.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Six of the ten strains were symbiotically efficient with diversity between those and the commercial chickpea strain CC1192. High temperatures significantly affected strain survival in liquid and peat carrier. Peat carrier offered greater protection. Above 37 °C, strain infectivity decreased with no correlation between strain origin and their infectivity after exposure. Three of the new strains and CC1192 produced optimum growth and survival at pH 6.8 and at two lower pH’s of 4.4 and 5.4 were able to neutralize the growth medium while the other seven strains at high pH were able to either neutralize or acidify the growth medium. Strain survival was significantly higher at increased salt concentrations of NaCl compared to CaCl<jats:sub>2</jats:sub>. At 3% NaCl concentration, 8 strains survived while at 3% CaCl<jats:sub>2</jats:sub> only 3 survived<jats:sub>.</jats:sub> Many strains were resistant to more than one antibiotic. All strains were able to solubilize phosphate. The ratio between the most efficient strain and the least was 3:1.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Chickpea rhizobia strains sourced from soils in Narrabri New South Wales and Kununurra in Western Australia differed in expressed traits from the commercial strain CC1192. These unique traits could provide additional tools for rhizobial strain selection to benefit chickpea production in different soil environments.</jats:p> </jats:sec>