Cd对蒌蒿生理生化及叶片超微结构的影响

Effects of Cd on physiology and biochemistry and leaf ultrastructure of Seleng wormwood

关键词:  蒌蒿  Cd  生理生化  超微结构

Key words:  Seleng wormwood  cadmium  physiology and biochemistry  ultrastructure

摘要:

采用Cd砂土污染试验,研究了Cd对蒌蒿生理生化特征及叶片超微结构的影响,结果表明在砂土Cd含量>180 mg/kg,蒌蒿出现中毒症状,叶绿素含量、a/b值、POD含量均下降,MDA积累,膜质过氧化,叶绿体形状球形化、片层结构解体、双层膜边界模糊、嗜锇颗粒增多,细胞核形状凹陷,核质分布不均匀、染色质凝胶化。低于180 mg/kg的砂土Cd浓度,蒌蒿的上述生理生化指标和叶片超微结构基本正常。蒌蒿可以耐受的Cd浓度不超过180 mg/kg。

Abstract:

The physiology and biochemistry and leaf ultrastructure of Seleng woodworm were discribed in the experiment with the sandy medium polluted by Cd. The plant treated with the Cd concentration over 180 mg/kg,the assimilation of MDA and relative electricity rate and reduction of POD concentration were observed in leaves. Cd treatment was shown to damage the structure of chloroplasts,as manifested by the swelled shape and the dilation of the thylakoid membranes. Moreover,ultrastructure of cell nuclei was damaged in certain degree,such as shape deformation and nuclei distribution unevenness and chromatin gelatinization. But less than 180 mg/kg Cd,non toxicity of Seleng wormwood was showed for almost treatments,so the Cd resistance range of Seleng wormwood could not be over 180 mg/kg.