摘要： 为研究盐胁迫对棉花超微结构的影响，用透射电子显微镜对NaCl胁迫下的棉花叶片和根系进行了观察和分析。结果表明，未胁迫的棉花叶片及根系细胞中各细胞器结构完整，而0.3% NaCl胁迫3 d后，引起了6个棉花品种超微结构的变化，其中，中50、N52、N203和K-1叶绿体形状改变，膜变得模糊，基粒片层结构分散，其中有部分叶绿体受损极为严重，包括类囊体排列紊乱、扭曲、松散，部分类囊体膜解体、空泡化，甚至消失，嗜锇颗粒增多；而根细胞中线粒体数量增多，膜系统受到破坏，嵴减少甚至模糊，细胞核核膜、线粒体膜破裂，核内染色质高度凝缩，核发生降解，而中熟品种N177和N181受破坏较轻，有较为完整的线粒体和细胞壁。试验结果经综合分析显示，中熟棉花品种N177和N181具有与耐盐性相适应的解剖结构特点，其抗盐性较强。

关键词: 棉花, NaCl胁迫, 叶肉细胞, 根系细胞, 超微结构

Abstract: The ultrastructures of leaf and root in six cotton varieties under NaCl stress were studied using transmission electron microscope.The results showed that various organelles of mesophyll and root maintained morphological integrity under normal condition, while their ultrastructure changed under 0.3% NaCl stress.In mesophyll cells, the chloroplasts of Zhong 50, N52, N203 and K-1 began deformed, with ambiguity in membrane and disorganization in grana lamell.One part of chloroplasts was seriously destroyed.The arrangement of thylakoid was disordered, loosened and twisted.Some of the thylakoid membrane disintegrated and cavitated gradually, even disappeared.The hungry particles increased significantly.In root cells, the numbers of mitochondrion increased and the membrane systems destroyed.The cristaes of mitochondrion were reduced and even vague.The cytoplasm segregated from the cell wall, and the lamellae of nucleolus and mitochondrion suffered disruption.Meanwhile, the chromatin was polymerized and the cell nuclear was degraded.But the mid-maturing varieties N177 and N181 have been undamaged.The mitochondrion and the cell walls had been maintained morphological structure integrity completely.Comparative analysis indicated that the mid-maturing varieties N177 and N181 had anatomic adaptation to the salt stress.The above results showed that the salt resistance of N177 and N181 was stronger than the other four varieties.

Key words: Cotton, NaCl stress, Mesophyll cells, Root cells, Ultrastructure

中图分类号: 

• Q942.4