Scleroderris canker of Todo-fir in Hokkaido, Northern Japan.

This article examines ascospore and pycnospore discharge and germination. The causal fungus was psythrophilic, with an optimum growing temperature of 10 degree Celsius. Pathogenicity to Abies sachalinensis was ascertained by artificial inoculation and symptoms were induced also by spraying a pycnospore suspension on to untreated shoots. Results of inoculation-experiments using both mycelium and pycnospore suspensions were always positive. On shoots inoculated in autumn, lesions were produced in the following spring. The lesions were larger when the inoculated shoot was first damaged with dry ice.