Trichoderma atroviride as a promising biocontrol agent in seed coating for reducing Fusarium damping‐off on maize

Coninck, Eugénie [UCL] Scauflaire, Jonathan [UCL] Gollier, Mélanie [UCL] Lienard, Charlotte [UCL] Foucart, Guy [UCL] Manssens, G. [UCL] Munaut, Francoise [UCL] Legrève, Anne [UCL]

Aims: The objective of this work was to identify a fungal strain showing potential biocontrol abilities against two Fusarium damping-off agents and to test it as a Biological Control Agent (BCA) in maize seed coating under field conditions. Methods and Results: A collection of native fungal strains associated with maize in Belgium was screened for antagonistic potential against Fusarium avenaceum and Fusarium culmorum. The strain with highest biocontrol potential was identified as an endophytic Trichoderma atroviride BC0584. In greenhouse, it significantly improves the emergence of seedlings infected by F. avenaceum or F. culmorum pathogens. In most field trials carried out during the season 2017, it significantly increased the emergence rate of infected seedlings compared to untreated seeds. One slurriable powder formulation allows BCA conidia to survive over a 6-month storage period at 4°C. Conclusions: The fungal BC0584 strain is a promising BCA that could be an alternative to synthetic fungicides. It is adapted to local environmental conditions, is easily and cheaply produced and can be stored in a low-cost formulation. Significance and Impact of the Study: In Belgium, this is the first study to use a T. atroviride native strain against Fusarium damping-off on maize crop. Modes of action and required conditions for ensuring high biocontrol activity in the field have still to be investigated.