Suitable nitrogen application mode and lateral spacing for drip-irrigated winter wheat in North China Plain

To propose an appropriate nitrogen application mode and suitable drip irrigation lateral spacing, a field experiment was conducted during 2017-2018 and 2018-2019 growing seasons to quantify the different drip irrigation lateral spacings and nitrogen fertigation strategies effects on winter wheat growth, yield, and water use efficiency (WUE) in the North China Plain (NCP). The experiment consisted of three drip irrigation lateral spacing (LS) (40, 60, and 80 cm, referred to as D-40, D-60,D- and D-80 respectively) and three percentage splits of nitrogen application modes (NAM) (basal and top dressing application ratio as 50:50 (N-50:50), 25:75 (N-25:75), and 0:100 (N0-100) respectively). The experimental findings depicted that yield and its components, and WUE were markedly affected by LS and NAM. Fertigation of winter wheat at N-25:75 NAM notably (P<0.05) increased the grain yield by 4.88%, 1.83% and 8.03%, 4.61%, and WUE by 3.10%, 3.18% and 5.37%, 7.82%, compared with those at NAM N-50:50 and N-0:100 in 2017-2018 and 2018-2019 growing seasons, respectively. LS D-40 appeared very fruitful in terms of soil moisture and nitrogen distribution, WUE, grain yield, and yield components than that of other LS levels. The maximum grain yield (8.73 and 9.40 t ha(-1)) and WUE (1.70 and 1.95 kg m(-3)) were obtained under D40N25:75 during both growing seasons, which mainly due to that all main yield components in D40N25:75 treatment, such as spikes per unit area, 1000-grain weight, and grains per spike were significantly higher as compared to other treatments. The outcomes of this research may provide a scientific basis of lateral spacing and nitrogen fertigation management for the production of drip-irrigated winter wheat in NCP.

Automated summary

The study aimed to determine the effects of different drip irrigation lateral spacings and nitrogen fertigation strategies on winter wheat growth, yield, and water use efficiency in the North China Plain. The experiment revealed that a drip irrigation lateral spacing of 40 cm and a nitrogen application mode of 25:75 significantly increased grain yield and water use efficiency compared to other settings. These findings provide valuable insights for the management of drip-irrigated winter wheat in the NCP.