Isolation and characterization of potential PGPR bacteria from the rhizosphere of regional crops

FABIAN E. LOPEZ; ADLER, C.; CARAM DI SANTO MC; POMARES M.F.; DE CRISTOBAL R.E.; LOPEZ, F. E.; VINCENT P. A.; MICHAVILA, G

BUENOS AIRES

Congreso; SAIB 2013; 2013

Sociedad Argentina de Investigaciones Bioquimicas y de Biologia Molecular

Isolation and characterization of potential PGPR bacteria from the rhizosphere of regional crops Michavila G, Adler C, Caram Di Santo MC, Pomares MF, de Cristobal RE, Lopez FE, Vincent PA Depot. Bioquimica de la nutricion-INSIBIO (UNT-CONICET). Instituto de Química Biológica (UNT) The bacteria that inhabit the rhizosphere and have ability to cause a positive effect on plants arecalled plant growth promoting Rhizobacteria (PGPR). In general, biological control mechanisms andplant growth promotion by rhizospheric bacteria are based on microbial metabolites that adversely affect the pathogen or induce systemic resistance in the plant. Our laboratory addressed a screening for rhizospheric bacteria featuring plant promoting traits and antibiotic action against plant pathogens.Pseudomonas and Enterobacter bacterial genera were isolated from soy rhizosphere and Bacillus,Burkholderia, Rhizobium, Pantoea, from sugar cane rhizosphere. We studied biochemical markersassociated with growth promotion i.e. siderophore production, synthesis of indole acetic acid andphosphate solubilization. We found that three isolates from sugar cane showed antibiotic activity against the pathogen Acidoboraxavenae. Moreover, one Pseudomonas strain from soy inhibitedXanthomonas campestri pv. campestri. Preliminary in vivo assays using soy plants showed a protective effect of the Pseudomonas strain against the causal agent of ringspot disease in soy (Corynespora casiicola). However, no antibiotic activity was observed in vitro. These results indicatea promising role of this Pseudomonas strain as a biocontrol agent for plant diseases through theinduction of the plant defense response.