【摘要】 在田间的小麦丛矮病非典型病株申常常分离到北方禾谷花叶病毒(NCMV)及玉米粗缩病毒(MRDV)两种病原物。单独用前者接种,仅表现小麦丛矮症,单独用后者接种,仅表现小麦蓝矮症,即植株矮化、暗绿、分蘖减少,叶坚挺。两者混合侵染时,往往表现两者的混合症状,但以何种病毒占优势而倾向于优势病毒的症状。典型丛矮症植株中电镜检出弹状病毒粒体,40—70×270—400nm尺度与日本报导的稍异。典型丛矮病株中不存在玉米粗缩病毒的粒体。小麦丛矮病毒很可能是北方禾谷花叶病毒的一种地方性株系。更多还原

【Abstract】 In North China a rosette disease of wheat had been revealed to be causedby the northern cereal mosaic virus(NCMV).However,from wheatplants wi-th rosette symptoms collected from fields a virus entity similar to the maizerough dwarf virus(MRDV)was frequently isolated in addition to the northerncereal mosaic virus.Both viruses were transmitted by the planthopper Ladel-phax strietellus.The wheat plants infected-by the northern cereal mosaic virusalone showed chlorotic stripes and streaks on leaves,abnormal abundance of til-lering and various degrees of dwarfing.The wheat plants infected by the MR-DV alone showed dwarfing of the plants,darkening of the green leaves(blucdwarf)and stiffness of the leaf blades.Furthermore the number of tillers mi-ght be reduced and heading was poor.Inoculation tests demonstrated that NC-MV did not attack maize.In the mixed-infections of the two virusse in whe-at plants,the symptoms were either of the NCMV type or of the MRVD ty-pe according to the predominance of one of the two viruses in the plants.Ge-nerally the symptoms of NCMV might mask the MRDV symptoms.Electronmicroscopic studies of the ultrathin sections of the NCMV infected wheat leavesrevealed bullet-shaped particles measured 40—70×270—400 nm,This measure-ment is littl(?)different from that of Japanese author.No MRDV particles werefound in the above studied ultrathin sectionsof typical rosette deiseased wheatleaves.The writers are of the opinion that the causal virus enitity of the rosettedisease of wheat in North China is one of the regional strains of the northerncereal mosaic virus,however,the MRDV-might frequently be present in thediseased plants in fields.更多还原