2.5. Invasive growth plate-washing assay
The invasiveness of the thirteen strains chosen for the detailed trials wereassessedinPetriplateswiththemediausedforthematassaycon-taining 2% agar. The trials were carried out according to
Bester et al (2006) modified as follows. Overnight cultures (20μL) were spotted onto the different plates and incubated at 28 °C for 6 days. Then, each strain biomass was removed from the surface with water gently rubbing with a finger in order to reveal cells remaining attached to or in filtrated into the media, reported in the following as footprints. Photographs were taken before and after the washing.