Isolation and Identification of Fomesafen-tolerant rhizospheric microorganisms from crops

SARAN ANABEL; DANIEL CAPELLINO; FERNANDEZ LUCIA ; MERINI, LUCIANO JOSE

Jinzhou

Congreso; The 7th International Conference on Agricultural and Biological Sciences (ABS 2021); 2021

After introduced in America, fomesafen (FSA) soon became one of the most frequently used herbicide in soybeans and other crops, because of its high herbicidal activity at low application rates. On the other hand, this herbicide residues persist for a long time in the soil and water, leading to phytotoxicity and damage in crop rotation. In this context, there is an increasing need to find eco-friendly and cost-effective techniques to remediate FSA polluted soils. The aim of this work was to isolate FSA-tolerant microorganisms present in bulk soil and the rhizosphere of different crops exposed to a standard and double agronomical doses of FSA on field. Two FSA degrading bacteria were isolated and identified as Burkholderia ubonensis and Burkholderia territorii based on the comparative analysis of 16S rRNA gene. These strains are able to grow using FSA as sole carbon source and exhibit multiple plant growth promotion (PGP) capabilities, standing out the phosphate solubilization, nitrogen fixation, Indol Acetic Acid and biofilm production. They also promoted germination of Helianthus annuus seed, although root elongation promotion was not observed on VAPs analysis. In addition the fungus Cladosporium sp., was also found in the bulk soil and Triticale rhizosphere. Its interaction with B. ubonensis and B. territorii was studied to assess the prospect of generating consortia for bioaugmentation purposes. Although this is a preliminary and exploratory study, these strains could enhance the extensive use of FSA, helping to reduce its residually on field.