Fig. 6.

Pathogenicity test of Hymenoscyphus species on European ash, F. excelsior, stems. Necrosis developed on the stems inoculated with H. fraxineus (d–f), H, koreanus (g–i), H. occultus (j–l) and H. albidus (m–o). Sterile plugs were used as control (a–c)