Effects of tillage during fallow period on soil water and wheat yield of dryland

As one of the major food for human survival and the important source for calories and protein, wheat has high priority in Chinese agricultural production. However, wheat production on dryland in Shanxi province of North China, a major wheat production region, was low and unstable, which was mainly due to the extreme variability in precipitation during the growing period, as well as the low capacity of soil water content (SWC) and water retention.Two-factors split-plot design was used in this study to evaluate the effects of tillage during wheat fallow period on soil water content (SWC), water use efficiency (WUE) and wheat yield in 2010~2011 in North China. The SWC of 0~300 cm depth soil, the SWC of every soil layer at 0~300 cm depth before sowing, wheat yield and WUE can all be enhanced under DT and SS systems, furthermore, the effect of tillage on the 45th day after the harvest was better than on the 15th day. Results also demonstrated that under tillage during the fallow period, the SWC of middle layer and deep layer before sowing had significant or extremely significant correlation with the spike number and wheat yield. All above suggest that tillage during the wheat fallow period can increase SWC at the depth of 80~160 cm, and thereby increase WUE, spike number and the yield of dryland wheat. The effects of three tillage systems (DT, SS and NT) during wheat fallow period in North China were investigated, and tillage performed better than NT on dryland which