sp. DBA51 produces ACC deaminase and promotes the growth of tomato ( L.) and tobacco ( L.) plants under greenhouse condition.

Bacterial isolated from rhizospheric soil associated with the semi-desertic plant L. were screened for 1-aminocyclopropane-1-carboxylate deaminase (ACCD) activity, a common trait for plant-growth-promoting rhizobacteria (PGPR). Among bacterial isolates, strain DBA51 showed phosphate solubilizing index (PSI), producing indole acetic acid (IAA), and with the hemolysis-negative test. Sequencing and analysis of the 16S rDNA gene identified DBA51 as . DBA51 did not show antagonistic activity against bacterial ( pv. DC3000 and FHLGJ22) and fungal phytopathogens ( sp., fsp. fsp. M5, and sp.). Root inoculations with DBA51 in tomato ( L.) and tobacco ( L.) plants were performed under greenhouse conditions. Plant height (20 %) and root biomass (40 %) were significantly enhanced in tomato plants inoculated with DBA51 compared to non-inoculated plants, although for tobacco plants, only root biomass (27 %) showed significant differences with DBA51. In addition, physiological parameters such as photosynthetic rate (µmol CO  ), stomatal conductance (mol HO  ), and transpiration rate (mmol HO  ) were also evaluated, and no differences were detected between DBA51-inoculated and control treatment in tomato and tobacco leaves. The observed results indicate that the DBA51 strain could be used as a biofertilizer to improve yields of horticultural crops.