镉对植物光合作用及氮代谢影响研究进展

镉是毒性最强的环境污染物之一。植物中积累的镉可通过食物链进入人体,给人类健康带来潜在危害。镉能抑制植物生长,能使植物形态、生理生化及结构发生改变。镉可减少净光合速率,损伤光合器官;使叶绿素含量下降;抑制气孔开放,从而影响植物的光合作用;镉通过改变植物硝酸还原酶(NR)、谷胺酰氨合成酶(GS)、谷氨酸合成酶(GOGAT)以及谷氨酸脱氢酶(GDH)的活性,进一步影响植物氮代谢过程。光合作用及氮代谢在植物生长发育过程中起着十分重要的作用,综述了重金属镉对植物光合作用及氮代谢的影响,并对其机理进行了探讨。

Advances on Investigation of Effect of Cadmium on Photosynthesis and Nitrogen Metabolism of Plant

Cadmium (Cd) is one of toxic heavy metals, which represents as potential threat to human health. The presence of Cd in the rhizosphere can inhibit the plant growth, cause alterations in morphological and physiological disorders in plants, affect several plant metabolic processes, such as photosynthesis,nitrogen metabolism. Cd can decrease photosynthetic rate (Pn), injure the organ of photosynthesis, decrease chlorophyll content, and inhibit stomatal opening which can affect the photosynthesis of plant. Moreover, the activities of nitrate reductase (NR), glutamine synthase (GS), glutamate synthase (GOGAT) and glutamate dehydrogenase (GDH) are affected by Cd which can induce changes of the process of nitrogen metabolism. Photosynthesis and nitrogen metabolism play an important role in growth and development of plant. Effect and mechanism of cadmium on photosynthesis and nitrogen metabolism of plant were reviewed in this paper.