Visualization of wound periderm and hyphal profiles in pine stems inoculated with the pitch canker fungus Fusarium circinatum.

Postpenetration behavior of Fusarium circinatum in stems of pine species was investigated with light and transmission electron microscopy. Two-year-old stems of Pinus rigida and P. densiflora were wound-inoculated with the fungal conidial suspension and subjected to 25 degrees C for up to 30 days.