Global warming and escalating water scarcity exert substantial impacts on crop production worldwide. Irrigation management is an effective strategy for winter wheat cultivation in the northern part of China, conserving water while sustaining high yields; however, its regional suitability and optimal management paradigm still lack exploration. Here, using the literature data from irrigation control experiments in the northern part of China (2000–2024), we conducted a meta-analysis to quantify the effects of deficit irrigation on winter wheat yield and water productivity (WP), and to identify its key influencing factors. The results demonstrate that deficit irrigation increases WP by 1.61% while reducing yield by 16.97%. Climatic and soil conditions jointly influence the suitability of deficit irrigation for winter wheat. Furthermore, the zones suitable for the deficit irrigation of winter wheat are determined firstly in this study, where WP improved and yield remains comparable to that under full irrigation. They are characterized by either a field capacity of 36.3% or less combined with soil bulk density greater than 1.45 g/cm³ and mean annual precipitation not exceeding 632 mm, or a field capacity above 36.3% coupled with soil bulk density exceeding 1.39 g/cm³ . These findings provide firstly farmers with quantitative evidence and suitable zones of the deficit irrigation. • Deficit irrigation increased winter wheat WP by 1.61% but reduced yield by 16.97%. • Both climate and soil factors jointly determine the suitability of deficit irrigation. • A Conditional Inference Tree approach identified key determinants of yield and WP. • Quantitative standards for deficit irrigation suitability in the northern part of China were established firstly.
Fang et al. (Thu,) studied this question.