Orchardgrass clonal lines were used to maintain not only stem rust of orchardgrass, but also stem rust of timothy or ryegrass. The differentiation of three formae speciales were successful with some of these clonal lines. These facts indicate that three rusts are closely related each other.
The diminishing effect of an antibiotic, Kasugamycin, on rice blast fungus has been a serious problem since 1971 in Shonai district, Yamagata Prefecture. Most isolates of the fungus from this district showed resistance to this antibiotic in plate and field tests. Such endemic occurrence could be related to the exclusive and frequent usage of this antibiotic for these several years in this district.