福州地区甘蔗黄叶病病原分子鉴定及电镜检测

电镜观察表明，感病甘蔗叶片的韧皮部伴胞内存在着大量类似甘蔗黄叶病毒（SCYLV）的病毒粒子；利用RT-PCR扩增出556 bp的目的片段，氨基酸和核苷酸序列分析表明，该片段是SCYLV外壳蛋白基因的一部分，与其他国家SCYLV分离物同源性达95%以上；应用组织印迹杂交免疫检测技术，在YLS病症的叶片中脉韧皮部出现紫红色斑块，呈阳性反应。综合分析认为福州地区甘蔗黄叶病的病原体为SCYLV。

Molecular Identification and Electron Microscopy Detection for Pathogen of Sugarcane Yellow Leaf Syndrome in Fuzhou

Causal organism of sugarcane yellow leaf syndrome (YLS) was identified by electron micrographs, RT-PCR and tissue blot immunoassay (TBIA) in Fuzhou, China. Virus particles like sugarcane yellow leaf virus (SCYLV) were found in phloem companion cells from plant with YLS symptoms by electron micrographs. A 556 bp fragment was amplified by RT-PCR. The sequences of cDNA and its amino acids suggested that the fragment was a part of gene of coat protein that shared above 95% homology with SCYLV isolates from other countries. Positive reaction appeared as dark purple spot at the location of the phloem cells by TBIA. The above results suggested that pathogen of sugarcane yellow leaf syndrome is SCYLV in Fuzhou.