A selective medium for enumerating low populations of Thielaviopsis basicola in tobacco field soils.
A selective medium (TB-CEN) is described for the quantitative isolation of T. basicola from naturally infested tobacco field soils containing low population densities. The medium contains etridiazole and nystatin as selective inhibitors of undesired fungi, and unautoclaved carrot extract for selective enhancement. The pour-plate technique, with incubation at 16-22°C, yielded the greatest recovery of T. basicola on TB-CEN. The medium was as sensitive as carrot-discs, and better than 3 other selective media, for isolating T. basicola from tobacco field soils.