Quantification of the potential biocontrol and direct plant growth promotion abilities based on multiple biological traits distinguish different groups of Pseudomonas spp isolates.

AGARAS, B; SCANDIANI M; LUQUE A; FERNANDEZ L; FARINA F; CARMONA M; GALLY M; ROMERO A; WALL LG; VALVERDE CF

BIOLOGICAL CONTROL

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2015 vol. 93 p. 173 - 186

1049-9644

Members of the Pseudomonas genus colonize the rhizosphere of different plant species and displayplant-probiotic traits. Therefore, they are interesting candidates for biological agricultural inputs to stimulateplant development and/or promote crop health. We have generated a collection of 19 isolates ofpseudomonads obtained from either bulk soil or the rhizosphere of healthy individuals of major extensivecrops from different plots under no-till management located in Argentina. Isolates were selectedfor their ability to antagonize several fungal pathogens recovered from infected soybean and maizeplants. Partial sequencing of 16S rDNA, oprF and rpoB genes positioned isolates within all major pseudomonadsgroups. Most isolates colonized the rhizosphere of soybean and maize seedlings withoutaffecting germination or development. Members of the Pseudomonas chlororaphis subgroup, and one isolateof the Pseudomonas putida subgroup, displayed the widest antifungal spectrum and strongest antagonisticpotential. A principal component analysis based on the outcome of quantitative and qualitativetests related to biocontrol of fungal pathogens, direct plant growth promotion, and other rootcolonization-related traits, showed that isolates with the highest antagonistic potential and mostly of soilorigin were grouped together, whereas rhizospheric isolates and those with strong flagellar-dependentmotility, exoprotease production and biofilm development, were clustered in a separate group.