Root morphology and physiological of their relationship with nitrogen uptake in wheat (Triticum aestivum L.)

Nitrogen (N) application is believed to improve photosynthesis in flag leaf ultimately increase final yield. The main results at 20-30 days after anthesis, the activities of superoxide dismutase (SOD) and peroxidase (POD) and soluble protein in flag leaves of N150 were found to be the most effective. Increased root weight density, root length density and root volume density at flowering stage, up to 10.6 %, 15.0 %, respectively. The root weight density, root length density and root bulk density at flowering and mature stages were the highest at the N180. Delaying the senescence physiology of post flowering leaves in the middle, and late stage, photosynthesis of leaves in the middle and late stage, improving the light energy interception of wheat, and then improving the light energy utilization efficiency. The stomatal conductance of flag leaves 15-30 days after anthesis, the maximum potential photochemical efficiency 20-30 days after anthesis, and the photochemical quenching of flag leaves 25-30 days after anthesis, and improved the light energy utilization efficiency by 9.6%-11.1 %. Yunhan-20410 the gene expressions of TaTZF1, TaNCY1, TaNCY3 and TaAKaGall in wheat flag leaves were significantly up-regulated YH-20410 gene expressions of N application treatment were significantly up-regulated compared with no N application treatment. The goal of high yield high efficiency, and high quality can be achieved by YH-20410 and combined to N180 kg ha^-1. The senescence physiology and gene expression of post flowering leaves in the middle and late stage, prolonging the photosynthesis of leaves in the middle and late stage, improving the light energy interception of canopy, and then improving the light energy utilization efficiency.