Fungal growth inhibition assays.

For fungal growth inhibition assays, agar plugs harboring actively growing F. graminearum HM6PIS were placed into the middle of YMG agar plates. Then, P. luminescens 1° and 2° cells and P. simiae WCS417 were cultivated overnight in LB medium with or without 3% (vol/vol) root exudates at 30°C. Cultures were adjusted to an OD₆₀₀ of 2. Then, four 50-μl aliquots were spotted and square connected around the fungal plug. The plates were further incubated at 26°C, and fungal growth was observed over 14 days. The experiment was repeated three times.