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Cercospora blight caused by Cercospora asparagi routinely developed on asparagus in certain plastic hoop houses in Hiroshima Prefecture in western Japan every July to November. Stemphylium lycopersici was repeatedly isolated with C. asparagi from the blighted leaves in September 2016 and shown to be another causal agent of the blighting and added as another pathogen causing Stemphylium leaf spot of asparagus.

Fusarium asiaticum was repeatedly isolated from blighted spikes of durum wheat with head blight-like symptoms in our experimental fields in Fukuyama, Hiroshima Prefecture in western Japan, then demonstrated to be pathogenic to the crop. F. asiaticum was not previously reported as causing head blight on durum wheat, so it has been added to the pathogens causing this disease.

Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after inoculation. Moreover, the 3-acetyl deoxynivalenol chemotype and the nivalenol chemotype were found in the isolates. We propose to include F. asiaticum as one of the pathogens causing Gibberella ear rot of corn in Japan.

The distribution pattern and frequency of isolates of a snow mold fungus, Typhula ishikariensis biotype A belonging to a predominant MCG (mycelial compatibility group, referred to as super MCG), were surveyed throughout its habitat from northern Honshu to eastern Hokkaido. About 38 and 14% of isolates examined belonged to super MCG in eastern and central Hokkaido, respectively ; however, super MCG was never found in southern Hokkaido or northern Honshu. These findings imply that T. ishikariensis biotype A consists of two populations in Japan, i.e., one that is distributed in Honshu and southern Hokkaido and lacks super MCG isolates, and the other that includes super MCG isolates and exists in central and eastern Hokkaido. The difference in distribution pattern of the two populations is discussed in terms of geological history during the Pleistocene (2 million to 10 thousand years ago). The tendency of global warming, which alleviates freezing damage, was considered to be responsible for the outbreak of this fungus in eastern Hokkaido.

A method was developed for assessing the resistance of wheat to speckled snow mold (Typhula ishikariensis) under controlled conditions in all steps. We modified the method of Nakajima and Abe and estimated the optimum conditions consisting of 2 weeks each for prehardening and hardening, 6 weeks for incubation at 8°C, and 2 weeks for regrowth in a greenhouse for screening resistance. The present method reduced the experimental period to 12 weeks and facilitated repeated experiments throughout the year.