Abstract
In Japan, 1967, unknown bacterial plant disease suddenly broke out on the fall sown oats field from March to May. The lesions of the leaf-blade were, at first small water-soaked, translucent specks, then gradually became elongate in the interveinal parenchyma to form brownish, translucent streaks. Among oats cultivated German Black was heavily infected, whilst White-Tarter was lightly attacked, but not North China. From its bacteriological characters of the isolates resembling to those of Pseudomonas coronafaciens, the symptoms of this oats disease, the authors identify the pathogen with Pseudomonas striafaciens (ELLIOTT) STARR et BURKHOLDER. The bacteriological characters of the pathogen are as follows : Cylindrical rods, 0.6〜1.2×1.8〜3.6μ, motile with 1 or 2 polar flagella, gram-negative. Aerobic, colonies on agar, pearl gray, round, raised, smooth, glistening and translucent. Brownish pigment produced in agar, but not fluorescin in KING'S agar. Gelatin liquefied and milk coagulated. Litmus and nitrates not reduced. Ammonia and levan produced, but not indol, hydrogen sulphide or acetoin. Metyl red negative. Acid but not gas produced from arabinose, xylose, glucose, fructose, galactose, mannose, sucrose, raffinose, glycerol, mannitol and sorbitol ; neither acid nor gas from rhamnose, lactose, maltose, starch, inulin, dextrin or salicin. Anaerobically neither acid nor gas from glucose. Aesculin and arbutin hydrolysed, starch and Tween 80 variable, but not margaline. Cytochrome oxidase and tyrosinase positive, but not oxidase, arginine dihydrolase or lecithinase. Oxidation of gluconate negative. Optimum pH and temperature, pH 6.6〜7.1 and 15°or 20℃, respectively. Thermal death point 47° or 49℃ Occurs naturally on Avena sativa. L.
