Enhancement of root architecture and nitrate transporter gene expression improves plant growth and nitrogen uptake under long-term low-nitrogen stress in barley (Hordeum vulgare L.) seedlings

Abstract Over application of nitrogen (N) fertilizers to crops ultimately causes N pollution in the ecosphere. Studying response plant growth and uptake low-N stress may aid elucidating mechanism low tolerance plants developing crop cultivars with high use efficiency (NUE). In this study, a high-NUE mutant line A9-29 wild-type barley cultivar Hua30 were subjected hydroponic culture supply, dry weight, accumulation, root morphology, expression levels potential genes involved nitrate assimilation measured at seedling stage. The results showed that under conditions, had higher content, influx rate larger area than did Hua30. Under long-term stress, compared Hua30, demonstrated HvNRT2/3 genes, especially HvNRT2.1 , HvNRT2.5 HvNRT3.3 . Similarly, including HvNIA1 HvNIR1 HvGS1_1 HvGS1_3 HvGLU2 increased significantly A9-29. Taken together, our suggested upregulation transporter contribute stronger capacity for accumulation responding stress. These findings understanding high-NUE.