白条黄单胞菌侵染对蔗叶和蔗茎组织超微结构的影响

Ultrastructure of sugarcane leaves and stem tissue infected by Xanthomonas albilineans

本研究利用普通光学显微镜、透射电镜和扫描电镜观察白条黄单胞菌[Xanthomonas albilineans(Ashby)Dowson]侵染后菌体定殖及对甘蔗叶片和蔗茎组织超微结构的影响。结果表明,白条黄单胞菌侵染后叶片的薄壁组织细胞膜裂解,木质部生长受到抑制。叶绿体形状多近圆形,基质片层解体,被膜破坏呈松弛状态,出现大量的原生质膜。扫描电镜可见白条黄单胞菌存在于各个叶肉细胞中,同时在维管束中也发现菌体定殖,特别是木质部导管。蔗茎的维管束被白条黄单胞菌堵塞,使得蔗茎木质化、木栓化严重。本研究有助于理解白条黄单胞菌对甘蔗叶片和蔗茎细胞内细胞器损伤的形态破坏,为白条病防治提供超微形态学依据。

Chloroplast variations in the leaf and the bacteria in tissue after being infected by Xanthomonas albilineans were observed by optical microscope,transmission electron microscope(TEM),and scanning electron microscope(SEM).After being infected by pathogen,the cell membrane of the thin-walled tissue was obscure,and the xylem growth was inhibited.The chloroplast was nearly circular,the lamellar structure was disasse-mbled,and its membranes were disrupted and relaxed,producing many plasma membranes.Scanning electron microscopy showed that bacteria residing in various mesophyll cells,especially bacteria localized in xylem and phloem vessels.The vascular stem bundles were filled with pathogens,resulting in stem lignification.These results provide a valuable refe-rence for further research on X.albilineans causing morphological damage to sugarcane.