摘 要：
发生在山东泰安及甘肃的小麦细菌性条斑病,经测定是由Xanthomonas translucens f. sp. undulosa (Smith et al.) Hagborg引起的小麦黑颖病。病叶呈水渍状斑点,后变黄扩大为黑褐色条斑,有菌浓。菌体短杆,尺度为0.4～0.8×1～2.5μ,无芽孢及荚膜,单个极鞭;格兰氏染色负性;菌落腊黄、圆、光滑、中凸、粘稠,在斜面上丝状;使营养液混浊,有表膜;使葡萄糖、蔗糖、果糖、乳糖、木糖及甘露糖等液变酸,不使麦芽糖、菊糖、甘露醇及水杨苷等变酸;不水解淀粉,液化明胶;不使硝酸盐产生亚硝酸;产生硫化氢及氨;不产生吲哚;石蕊牛乳凝集并胨化、微碱性。病原细菌除为害小麦外,经接种可侵染大麦及黑麦,而燕麦不感染。20个小麦品种及品系苗期测定,都表现感病。
译 名：
STUDIES OF XANTHOMNAS TRANSLUCENS f.sp.UNDLOSA IN WHEAT
作 者：
Chen DoRen, Ding AiYun (Shantung Agricultural College)
摘 要：
A leaf-stripe disease occurred on wheat in the wheat growing region of Taian, Shantung and Kansu provinces. The causal organism of this disease has been identified as a form of Xanthomonas translucens f. sp. undulosa (Smith et al.) Hagborg.The disease shows translucent and water-soaked spots on the infected leaves which become yellow, then darker and black stripes. Bacteria ooze appearcd on the infected surface as many tiny drops and later as yellow beads.The morphological and physiological characters of the pathogen are described as follows:Rods, 0.4～0.8×1.0～2.5u, single, occasionaly in pairs, but not in chains, no spores and capsules, motile by a single polar flagellum; Gram negative; beef-pepton agar colonies wax yellow, circular, smooth, entire, convex and very viscid; filiform on agar slant; turbidity in beef-broth with pellicle on surface; acid but no gas from glucose, sucrose, lactose, galactose, fructose, xylose, mannose; no acid from maltose, inulin, rhamnose, salicin; starch not hydrolyzed; gelatin liquefied;nitrates not reduced to nitrites; hydrogen sulphid and ammonia produced; no indole;milk coagulated and peptonized, and reaction of litmus slight alkaline.Inoculation studies with the bacterial isolates from leaf-stripe disease of wheat infected barley and rye, producing water-soaked streaks with bacterial exudates on leaf surface; but did not infect oats. Twenty varieties or cultivars of wheat seedlings are all susceptible to this organism.
