Abstract: Eighty-eight specimens of poplars infected with Marssonina, collected from nine provinces or autonomous regions in China, were examined. M. populi and M. castagnei were only found in specimens from Xinjiang. M. brunnea were found in the other provinces. The species pathogenic to poplars in Nanjing area should be M. brunnea, other than M. populi as reported previously. Host range tests of three Marssonina species and the relative susceptibility of various poplars to these fungi were conducted with artificial inoculation.

Key words: Marssonina species, Host range, Distribution