Tillage practices affect dry matter accumulation and grain yield in winter wheat in the North China Plain

• Rotary tillage after subsoiling with an interval of 2 years is the optimizing practices increased wheat yield and water use efficiency.
• Optimizing tillage practices promoted soil water consumption from jointing to maturity in the 80–180-cm soil layer.
• Optimizing tillage practice increased net photosynthesis rate from 20 DAA to 30 DAA and dry matter accumulation at maturity.

Tillage is an important management tool for tackling and promoting water conservation and improving crop yield in northern China, where winter wheat production is frequently threatened by drought. Although plowing (P) and rotary tillage (R) practices are widespread in the region, only few studies have focused on subsoiling. Three practices, namely P, R, and RS (rotary tillage every year and subsoiling interval of 2 years), were evaluated under field conditions over a period of 7 years. The average soil water consumption from RS increased by 24.6% and 69.0% compared to that from P and R, respectively, from sowing to jointing in the 40–100 cm soil layer, and increased by 54.2% and 81.6% compared to that from P and R, respectively, from jointing to maturity in the 80–180 cm soil layer. The net photosynthesis rate and stomatal conductance of flag leaf from RS treatment from 20 days after anthesis (DAA) to 30 DAA were significantly higher than those from P and R, which is likely the reason for the higher dry matter accumulation at maturity in RS than that in P and R. The 4-year average of grain yield and water use efficiency from RS increased by 22.7% and 37.0%, respectively, compared to that from P and by 7.7% and 11.9%, respectively, compared to that from R. Thus, RS is the best method for increasing grain yield and water use efficiency of winter wheat in northern China.