氮高效利用水稻碳氮代谢物含量的变化特征

Characteristics of Carbon and Nitrogen Metabolites of Rice Genotype with High Nitrogen Use Efficiency

采用土培盆栽试验,研究氮高效利用水稻在不同供氮水平下碳氮代谢物含量的变化情况,并探讨其与氮素利用效率之间的关系。结果表明,氮高效利用水稻碳氮代谢物谷氨酸(Glu)、谷氨酰胺(Gln)、α-酮戊二酸(2-OG)和蔗糖的含量随生育进程的变化态势与氮低效利用水稻大致相同,但其含量的高低因品种、施氮量不同而异。Glu对氮的响应基本为随施氮量增加而增加。Gln在抽穗期、开花期和2-OG在抽穗期、开花期、成熟期对氮响应呈现先降后升再降的"S"型曲线变化规律;蔗糖在抽穗期随施氮量的增加而减少,而在成熟期表现为增加。抽穗期Gln与Glu呈极显著正相关;氮利用效率(NUE)与开花期的Gln呈显著负相关,与Glu呈显著正相关,与成熟期2-OG呈极显著负相关。施氮量和不同氮利用效率水稻对碳氮代谢物含量有影响,氮高效利用水稻在低氮条件下具有较高的Glu、2-OG和蔗糖含量;抽穗期不同供氮处理Gln含量均明显较高。

Nitrogen plays important roles in promoting plant growth and development. The purpose of this study was to investigate how N nutrient affected the content changes of carbon and nitrogen metabolites in functional leaves un- der different nitrogen levels and their relations with nitrogen utilization efficiency of rice with high nitrogen use effi- ciency. The results showed that the change trends of glutamate （ Glu ）, glutamine （ Gin）, 2-oxoglutaric acid （2-OG） and sucrose in different growth stages of the two types of rice cultivars with different N use efficiency （NUE） were similar. But the differences in content would be changed by different varieties and nitrogen application. Glu response to nitrogen is increase with the increase of nitrogen application rate. With the increasing of nitrogen, Glu content was increased. Gln in heading and anthesis stage, 2-OG in heading, anthesis and mature stage appeared undulation of first falling, and then rising and failing again. With the increasing of nitrogen, sucrose content was reduced in head- ing stage, but increased in mature stage. A significant positive correlation was found between Gln and Glu in heading stage. NUE was negatively correlated with Gin, positive correlation with Glu in anthesis stage, negatively correlated with 2-OG in mature stage. There are significant effects of nitrogen level and rice cultivars with different NUE on carbon and nitrogen metabolisms. High NUE has high Glu ,2-OG and sucrose content in low nitrogen level,especial- ly high Gln content in heading stage at different nitrogen levels.