松江市の裁培セリに発生する病害について(第1報)

(1) From diaseased Japanese parsley (Oenanthe Javanica (BLUME) D.C.) cultured on paddy field at Kuroda in Matsue city, some bacteria and fungi were isolated. Three of these fungi, (Pythium sp. Sclerotinia sp.) were pathogenic to the suscept wounded artificially.
(2) Physiological characters on these fungi were investigated. Pythium sp. grows well on Japanese parsley decodtion, CZAPEK synthetic medium. Its optimum temperature and hyarogen-ion concentration seemd to be at 20℃, pH 6.5, respectively.
The formation of oogonium and oospore was recognized on the media adding haemoglobin. The optimum mycelial growth of Botryis sp. was obtained at around 20℃. pH4.5 respectively. Conidial germination of Botrytis sp. was fairly good at 20℃ but no germination was occured in relative humidity less than 84%.
(3)Mycelial growth of these fungi was checked on the media containing organic mercury compounds such as P.M.F and mercury acetylide E. The effect of copper compounds, such as Sankinon, Shin-fuji Bordeaux, and Griseofulvin, followed them but sulphur compounds and bacterial antibiotics were not effective against them.
(4) P.M.F. and mercury actiylide E showed their toxic injury to the suscept by spraying at the concentration of 2000 dilution or above. Pythium sp. and Sclerrotinia sp. were checked its growth after immersing the mycelium in the solution of malachite-green and P.M.F for 30 seconds. Inoculation of the pathogens to the suscept with wound after spraying malachite -green solution checked the appearance of disease symptom remarkably. The spraying of P.M.F and mercury acetylide E on Japanese persley cultured on paddy field was not effective within the scope of the writers' experiments.