以玉米杂交种郑单958成熟鲜果穗为材料，研究低温冻害对玉米种子盾片超微结构的影响。结果表明: -10 ℃处理8 h，玉米种子盾片细胞壁、细胞膜、线粒体和蛋白质体都受到不同程度的破坏，一些细胞局部发生轻微的质壁分离，线粒体内部结构紊乱，脊模糊难辨；蛋白质体膨胀液泡化。-20 ℃处理8 h，玉米种子盾片细胞发生严重的质壁分离，原生质膜受到破坏，丧失渗透调节功能，部分细胞液从细胞质中外渗，充斥在细胞膜和细胞壁之间；脂类小滴消失殆尽；核膜破坏、解体，核仁高度凝聚；线粒体膜破坏，脊的数量减少，甚至整个线粒体破损解体；由于各种生物膜的破坏，使细胞内充满许多囊状小泡，严重时细胞壁断裂，细胞器残体充斥在细胞间隙中。

The effect of freezing injury on ultrastructure of scutellum in corn (Zea mays L.) seed is researched. The result shows that the normal structure of scutellum in corn seed is destroyed after the treatment of freezing injury. In the treatment of -10 ℃ with 8 hours， the cell wall， plasma membrane， mitochondrion and protein bodies are injured in different degrees， some cells arose plasmolysis partially， the inside structure of mitochondrion become disordered and the crests are bushtailed and difficult to distinguish； Protein bodies are expanded and figured as a vacuole. In the treatment of -20 ℃ with 8 hours， ultrastructure of the plasma membrane， mitochondrion， protein bodies and all kinds of cellular organs are damaged badly. A lot of cells arose plasmolysis obviously， plasma membrane is destroyed and its function of diosmosis adjusting is lost， a part of cellular liquid osmosesed from cytoplasm and cellular cellular liquid osmosesed from cytoplasm and filled in the space between cell wall and plasma membrane； Lipoids almost vanished； The nuclear membranes are destroyed and disintegrated， nucleolus are highly condensed； The membrane of mitochondrion is destroyed， the quantity of crests in mitochondrion decreased， even wholly mitochondrion is disjointed； Because a series of bio-membrane system is destroyed， the cells are full of vesicles， even cell wall ruptured and the organ remains osmosesed to intercellular space.

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甘肃省自然科学基金项目(1308RJYL069)部分内容