Long‐term nitrogen addition impact on agronomic traits, nitrogen uptake and nitrogen resorption efficiency of wheat in a rainfed region
Aixia Xu, Lingling Li, Jeffrey A. Coulter, Junhong Xie, Renzhi Zhang, Zhuzhu Luo, Liqun Cai, Chang Liu, Linlin Wang
Abstract
Abstract Nitrogen (N) fertilizer management is one of the most important issues in wheat ( Triticum aestivum L.) production. To explore the mechanism of N uptake efficiency (NupE) and N resorption efficiency (NRE) in wheat, this study examined the effects of different N fertilizer application rates (0, 52.5, 105, 157.5, 157.5, and 210 kg N ha −1 yr −1 ) on crop growth parameters, NupE, NRE, and N use efficiency (NUE). The results of the 2‐yr (2018 and 2019) study showed that the growth of crops was enhanced in high‐N treatments, resulting in higher N concentration in wheat tissues. The 105 kg N ha −1 treatment (N105) was the best rate for improving spring wheat yield and NUE, ensuring the highest values of N uptake, evapotranspiration, and leaf NRE. Compared with the non‐N‐fertilized control, N105 increased grain yield and N uptake by 46.90 and 90.54%, respectively; thus, N105 had 16.40% higher NUE, 28.33% higher N utilization efficiency (NutE), and 0.58 kg kg −1 greater NupE. Therefore, N uptake and N resorption are of great importance for increasing NUE of wheat, and for improving the sustainability of wheat production in the semi‐arid Loess Plateau of China.