The Fusarium wilt disease of potatoes is prevalent in certain districts of Hokkaido and causes severe damage on the crop in recent years. The author described the symptoms in full and isolated 3 species of Fusaria from the affected potato plants, namely Fusarium oxysporum SCHLECHT. f. 1 WR., a variety of Fusarium Solani APP. et WR., and Fusarium avenaceum SACC. Among these Fusaria, Fusarium oxysporum SBHL. f. 1 WR. and a variety of Fusarium solani APP. et WR. were pathogenic and they caused typical potato wilt in infection experiments. The variety of F. solani was markedly virulent. The toxicity of fungus filtrates was proved to cause the wilting of the cuttings of potato shoots by experiments. Fusarium avenaceum, however, seems to cause only the rottings of stored potatoes and not the wilting in the field. (Jan., 1948)
Cotton plants at various growing stages were inoculated with a culture of Corticium vagum B. et C., isolated from a cotton seedling. The results of experiments showed that the cotton plant was invaded by the fungus throughout the growing stages. The susceptibility seems, however, to be reduced as the plant grows older. Percentage of infection of the seedlings was higher in wet soil than in dry soil but no remarkable difference was found as to grown plants. Inoculation experiments with the same fungus upon the grown-up hemp, abutilon, jute and flax showed that the isolate was also pathogenic to these fibre-plants tested.