Development of the fungus Ceratocystis fimbriata in shoots of poplar clones with differing resistance1

Abstract Differences in the development and rate of spread of C. fimbriata hyphae between susceptible, moderately resistant and resistant clones were observed. Conidia of various shapes and ascospores appeared in necrotic parts of shoots of susceptible and moderately resistant clones while in the resistant one only cylindrical conidia were present.