Response of Maize Growth and Yield to Different Water and Nitrogen Schemes on Very Coarse Sandy Loam Soil Under Sprinkler Irrigation in the Semi‐Arid Region of China

Abstract

AbstractFarmers are being encouraged to shift from conventional surface irrigation to sprinkler irrigation in the semi‐arid region where coarse‐textured soil is predominant in order to improve irrigation efficiency, but their irrigation and fertilization are currently scheduled by the traditional methods obtained from surface irrigation due to insufficient knowledge of the relatively new technology of sprinkler irrigation. This often results in an inefficient use of water and nutrients and a decreased crop yield. The objective of this paper was to quantify the response of maize growth, nitrogen uptake, yield, yield components, water productivity and nitrogen agronomic efficiency to different irrigation and nitrogen application rates under semi‐arid conditions and to determine an optimal irrigation and nitrogen regime for sprinkler irrigation. Field experiments were conducted on a very coarse sandy soil irrigated by a lateral move sprinkler system in the Inner Mongolia Autonomous Region in 2012 and 2013. Three irrigation levels of 40, 70 and 100% of evapotranspiration (ETc) and four nitrogen application rates of 80, 160, 240 and 320 kg ha‐1 were tested in 2012. Whereas in 2013, four irrigation levels of 40, 70, 100 and 130% of ETc and four nitrogen application rates similar to the 2012 experiments were used. For the very coarse soil tested, the irrigation level demonstrated a substantially more important influence on plant growth than nitrogen application rate. A higher irrigation level produced a significantly greater plant height, leaf area index (LAI), dry matter above ground, plant nitrogen uptake, yield and nitrogen agronomic efficiencies (NAE) when irrigation level was between 40 and 100% ETc. However, when the irrigation level exceeded 100% ETc, a reduced yield and NAE was observed. In 2012, the nitrogen application rate of 160 kg ha‐1 usually gave a slightly higher yield and irrigation water productivity (IWP). Whereas in 2013, the nitrogen application rate of 240 kg ha‐1 resulted in the greatest yield and IWP. No significant difference in yield, IWP and NAE was observed between the treatments with nitrogen application rates of 160 and 240 kg ha‐1 for both 2012 and 2013 experiments. A management practice of irrigation at 100% ETc, along with nitrogen application rate of 160 kg ha‐1, was therefore recommended. Copyright © 2015 John Wiley & Sons, Ltd.