1923 年 1 巻 5 号 p. 43-44
1. The spores of Cercospora beticola kept in dry condition at the laboratory were active for 16 months.
2. The spores infected in the seeds were able to germinate until the end of April (sowing season) of the next year.
3. The spores of diseased leaves kept under caves were not able to germinate in the beginning of May, but sclerotial bodies or mycelia in tissue were alive through the winter.
4. The spores of diseased leaves placed on the soil in the field of Suwon, lose thier vitality in the beginning of May but the sclerotial bodies or mycelia in tissue were very often able to germinate. The same result was obtained in Heijo, but a few spores on the under parts of the pile were able to germinate in the case where beet root were covered with thin layer of soil.
5. The spores of diseased leaves mixed with the wet soil died after 3 to 4 weeks, in the laboratory.