Effects of straw mulching on water consumption characteristics and yield of different types of summer maize plants

To develop rainfed agriculture in northern China, we conducted field experiments with three straw mulching rates (0, 6, and 12 t/ha) on two plant types (a compact type, Chaoshil, and a flat type, Danyu86) during the summer maize-growing season in 2009 and 2010 to study soil moisture content, evapotranspiration, grain yield, and water-use efficiency (WUE). The results indicated that straw mulching could significantly (LSD, P < 0.05) improve soil moisture content at a depth of 20-80 cm below the ground surface during the anthesis-silking stage; however, at maturity, straw mulching decreased the soil moisture content at a depth of 0-60 cm below the ground surface. In 2009, straw mulching at the rate of 12 t/ha significantly (LSD, P < 0.05) increased the evapotranspiration in Chaoshil and Danyu86. In 2010, straw mulching at the rate of 6 t/ha significantly (LSD, P < 0.05) increased evapotranspiration in Danyu86 alone. The grain yields of Danyu86 in 2009 and Chaoshil in 2010 were significantly (LSD, P < 0.05) higher with straw mulching at the rate of 12 t/ha than on the application of other treatments. Irrespective of whether precipitation was concentrated during the beginning or the latter half of the summer maize growing stage, straw mulching increased the WUE of Chaoshil, but not of Danyu86. These results indicated that under rainfed conditions in northern China, straw mulching could increase the grain yield and WUE of compact-type maize.