大气 CO2 浓度升高对水稻氮代谢影响的研究进展

自工业革命以来,大气中浓度不断升高的CO2对C3植物生长发育的影响十分显著。CO2浓度升高条件下,植物光合作用增强,C同化产物增多,C、N代谢的平衡受到影响,植株N代谢发生变化。水稻(Oryza sativa L.)作为世界上最主要的食物来源之一,其N素营养状况的变化必然引起人类食物品质的改变,近年来已成为人们关注的焦点。本文结合气室条件的研究结果,从水稻N吸收和N积累量、N浓度、N代谢相关酶、不同形态的N(主要是蛋白氮)、C/N比、根系含N分泌物以及N与光合适应的关系等方面,重点收集和整理开放式空气中CO2浓度升高(FACE,Free Air Carbon-dioxide Enrichment)条件下水稻对N素的吸收、分配和利用等方面的研究进展,并对有待进一步深入的问题进行了探讨。

Responses of nitrogen metabolism in rice plant to elevated atmospheric CO2 : A research review

The increasing concentration of atmospheric CO2 has significant effects on the growth and development of C3 plants. Enhanced carbohydrate accumulation in plant tissues as the result of stimulated photosynthesis under elevated atmospheric CO2 affects carbon and nitrogen metabolism, and might alter the balance between them. Rice (Oryza sativa L.) is one of the most important food resources in the world and the changed nitrogen content of the rice grain affecting the quality of human nutrition has become a hot issue. Mainly based on the data from FACE (Free Air Carbon-dioxide Enrichment) experiments and some results from chamber-based trials, this paper reviewed the effects of the elevated atmospheric CO2 on the nitrogen uptake, allocation and assimilation including the nitrogen uptake and accumulation, nitrogen concentration, enzymes related to nitrogen metabolism, different nitrogen forms (mainly the protein-N ), the ratio of nitrogen/carbon, root exudates containing nitrogen and the relationship between nitrogen status and photosynthetic acclimation. The further research directions in this field were discussed as well.