Cd^(2+)污染对莼菜叶片形态学伤害反应的研究

STUDIES ON THE POISONING SYMPTOMS AND THE MORPHOLOGICAL CHANGES OF THE LEAVES BLADE OF B.SCHREBERI INDUCED BY THE STRESS OF THE POLLUTION OF Cd^( 2+)

重点研究了Ｃｄ２＋胁迫下莼菜叶片的受害症状及叶肉细胞超微结构的变化。当Ｃｄ２＋浓度大于２μｇ·ｇ－１时，莼菜叶面将在短期内出现不同程度的受害症状。莼菜叶片遭受Ｃｄ２＋毒害初期，叶肉细胞质体中的少数基粒会发生膨胀或解体，线粒体的脊出现瓦解，部分核仁裂解成数块大小不等的颗粒。随着叶肉细胞遭受毒害程度的加深，质体中较多的类囊体便出现解体，多种膜性结构如：质体、线粒体的外包膜以及核膜、液泡膜等均遭破坏。还运用扫描电镜能谱对Ｃｄ２＋胁迫下莼菜叶片中Ｃｄ２＋的含量进行了检测。

This paper mainly deals with the poisoning symptoms and the ultrastructural changes of the mesophyll cells of B.schreberi induced by the stress of Cd 2+ .Different degree of poisoning symptoms always appear on the surface of the leaves blade in a short time when the density of Cd 2+ exceeds 2 μg·g -1 .At the primary stage when the leaves suffered the poison of Cd 2+ ,a few of plastids grana either swelled or disintegrated,the mitochondria cristea began to disintegrate and some nucleolus divided into several parts.With the increasing of the poison,most of the plastids grana of the mesophyll cells disintegrated.Several membrane structure,such as the outer membrane of plastids and the mitochondria and the membrane of nuclei and vacuoles,have suffered destruction.We have also inspected the relative content of Cd 2+ in the leaves which suffered thd Cd 2+ poison by means of the energy spectrum.