Rizospheric bacteria with antifungal potential against maize phytopatogens.

BIGATTON ED; AYOUB I; VÁZQUEZ C.; BERDINI A; ARCHILLA MV; BRUNO M ; DUBINI L ; PIZZOLITTO RP; MORENO V ; PRIETO MC; MERLO C ; LUCINI EI

Santiago del Estero

Congreso; 5º Congreso Argentino de Fitopatología.; 2021

Rhizobacteria of Bacillus genus con produce volatile organic compounds (VOCs) with the ability to reduce fungal growth and sporulation. The objective was to study the biocontroller effect of rhizobacteria of Bacillus genus against maize (Zea mays) phytopathogenic fungi. From rhizospheric soil of Córdoba agricultural fields (Argentina), 40 bacterial strains were isolated and genetically identified. To evaluate antifungal activity a suspension of each bacterial strains was inoculated onto a Petri plate with nutritive agar and incubated at 28°C for 24 h. Subsequently, a conidial suspension (of Fusarium verticillioides and Aspergillus flavus) was added at the center of the plate with PDA. Then, plates with bacteria and conidia were faced and sealed, and cultivated at 28°C for 7 days. The radial mycelial growth was determined by periodical measurement and growth inhibition percentage was calculated. Of the total of the isolated strains, 18 inhibited mycelial growth. The highest percentages were detected for the VOCs emitted by strains of B velezensis (RI1, RI2 and SI3), B. altitunidis (SI2) and B. tequilensis (SC1), which could inhibit 47%-55% of A. flavus growth. The strains showed less capacity of inhibit F. verticillioides growth. In conclusion, bacterial VOCs showed a biocontrolling effect, being higher against A. flavus. Future studies should be carried out to elucidate the action mechanisms of VOCs produced by bacteria, for bioinputs formulation.