甘蔗花叶病毒田间杂草寄主鉴定

正玉米矮花叶病1963年在美国俄亥俄州首次报道1],我国1968年在河南省首次报道。甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)是引起我国玉米矮花叶病的主要病原2, 3]。根据基因组序列的系统发育分析,SCMV分为4个组,其中第I组分布最广,第IV组是新发现的一个强毒株系,近年来的发生呈上升趋势4, 5]。SCMV属于马铃薯Y病毒属(Potyvirus),粒体为弯曲线状。其由蚜虫非持久性传播6],能侵

Identification of weed reservoir for sugarcane mosaic virus

Sugarcane mosaic virus (SCMV) is the prevalent virus causing maize dwarf mosaic in China. Here we collected 90 weed samples belonging to 15 species, among which Setaria viridis, Echinochloa crusgalli and Digitaria sanguinalis showed distinct mosaic symptom. The maize in-bred line B73 and cultivar Denghai 605 plants inoculated with extracts of S. viridis, E. crusgalli and D. sanguinalis showed distinct mosaic symptom in the systemically infected leaves at 10 days post-inoculation. ELISA results showed that samples of S. viridis, E. crusgalli and D. sanguinalis were positive to antibody against SCMV CP. The duplex-PCR showed that samples of S. viridis, E. crusgalli and D. sanguinalis were infected by SCMV which was not belonging to group IV. The SCMV ORF of 3 weed and one maize samples shared nucleotide and amino acid sequences identities of 93.1%-99.7%. Gene-flow analysis showed that the SCMV isolates from three weed samples had frequent gene flow with the SCMV isolates from maize in Shandong Province. Phylogenetic analysis showed that all the four SCMV isolates were clustered into group I. These results indicate that S. viridis, E. crusgalli and D. sanguinalis are weed reservoir of SCMV. These results provide theoretical guidance for the effective control of SCMV.