Figure 1.

Nitrogen source regulates invasive growth, hyphal aggregation and root adhesion via TOR and MeaB. (A) Effect of nitrogen source, MeaB and TOR on cellophane penetration by Fusarium oxysporum. Fungal colonies were grown 4 days at 28°C on plates covered with a cellophane membrane (before). The cellophane with the fungal colony was removed and plates were incubated for an additional day to determine the presence of mycelial growth on the plate (after). (B) Hyphal aggregates forming after 36 hours conidial germination. Cultures were vortexed to dissociate weakly adhered hyphae and observed in a binocular microscope. (C) Root adhesion assay. Roots of tomato seedlings were immersed for 36 hours in microconidial suspensions, then washed by vigorous shaking in water and observed in a binocular microscope. Adhering fungal mycelium is visible as a white mass covering the roots.