Effect of Planting Patterns and Seeding Rate on Dryland Wheat Yield Formation and Water Use Efficiency on the Loess Plateau, China

Dryland winter wheat (Triticum aestivum L.) production plays an extremely important role in the southeast of the Loess Plateau. Planting patterns have great influence on improving soil water storage and yield, and should be matched with different seeding rates. In order to assess the effect of different sowing methods on the drought resistance and stable yield of dryland wheat, a field experiment was conducted in Wenxi County Dryland Wheat Experimental Base in Shanxi Province, China. In the current study, the effects of three planting techniques (drilling sowing, furrow sowing, and film-mulched sowing) and four seeding rates (150, 225, 300, and 375 kg ha(-1)) were examined on water storage, dry matter formation, yield, and water use efficiency (WUE). The results showed that furrow sowing (FS) and film-mulched sowing (FM) treatments increased soil water storage in the 0-300 cm soil layer at overwintering and jointing stages. In addition, FS and FM increased soil water consumption in the 0-300 cm soil layer from overwintering to maturity of wheat. Furthermore, FS and FM significantly increased the dry matter accumulation from the overwintering to the mature stage, promoted its accumulation in vegetative organs and translocation to grains after anthesis, viz., increased yield by 6.2% and 7.9%, and WUE by 4.6% and 5.3%, respectively, as compared with those of the drilling sowing (DS) treatments. Pearson's correlation analysis showed that grain yield had a significantly positive correlation with soil water storage at overwintering and jointing. Moreover, grain yield was significantly positively correlated with soil water consumption in the 0-300 cm soil layer from jointing to maturity. Additionally, the seeding rate of 150 kg ha(-1) with FS could obtain higher WUE and grain yield. Therefore, it is strongly recommended that the seeding rate of 150 kg ha(-1) is used with FS to improve the grain yield and WUE of dryland agricultural systems in China.