南瓜幼茎中螺纹导管次生壁的发育  

Secondary Wall Formation of Helical Tracheary Elements in the Stem of Cucurbita Moschata

作　　者：许珊[1] 祝建[1] 钱洁[1] 

机构地区：[1]同济大学生命科学与技术学院,上海200092

出　　处：《同济大学学报（医学版）》2006年第6期12-15,23,共5页Journal of Tongji University(Medical Science)

基　　金：国家自然科学基金资助(30470863)

摘　　要：目的观察南瓜(Cucurbita moschata)茎螺纹导管发育过程中次生壁的形成过程。方法利用透射电镜对同一植株的不同茎段的螺纹导管次生壁及原生质体进行超微结构观察。结果螺纹导管次生壁发育早期,细胞具有较大的细胞核,细胞质浓稠,具有核糖体、线粒体和高尔基体等细胞器。初生壁与质膜之间有间隔较规律的次生壁突起;中期,线粒体和高尔基体的数量明显增加,细胞质中几乎充满高尔基体及其囊泡,次生壁中微纤丝已成有序排列;晚期,细胞核消失,导管中央形成空腔,细胞器迅速减少,仅观察到少量高尔基体和线粒体,有大量周质微管沿细胞长轴分布,且在次生壁的周围有大量小泡附着,次生壁的分层结构清晰可见。结论高尔基体及其分泌小泡和内质网等细胞器参与了导管次生壁的形成,其中周质微管也起了一定的作用。导管次生壁的形成与程序性细胞死亡(programmed cell death,PCD)密切相关。Objective To study secondary wall formation of helical tracheary elernents in the stem of Cucurbita moschata. Methods Ultrastructural changes in secondary wall formation and protoplast of of helical tracheary elements in the same stem of Cucurbita moschata were investigated with transmission electron microscopy. Results Secondary wall developed initially with the elongation of cells containing Golgi bodies and mitochondria in the dense cytoplasm. During the wall thickening, the number of Golgi bodies increased apparently and cytoplasm was filled with Golgi vesicles. Polylamellate structure of the secondary wall appeard . Along with the further development of tracheary elements, the nuclcous disappeared and organelles were decreased, while cortical microtubules were arranged neatly against the ilmer side of plasmaleJaama. Conclusion The organelles, such as Golgi bodies together with small vesicles, endioplasmic and reticulum play the key role in the formation of the secondary wall of helical tracheary elements in the stem of Cucurbita moschata, though cortical microtubules are correlative with the process as well. The fomaation of the secondary wall correlates with programmed cell death（PCD）.

关 键 词：螺纹导管 次生壁 超微结构 高尔基体 

分 类 号：Q944.2[生物学—植物学]