Effect of fertiliser application on the growth and water use efficiency of wheat in semi-arid area in North China Plain

Abstract

In order to classify the most important nutrients affecting growth and water use efficiency (WUE) of wheat and to improve the grain yield of wheat in semi-arid region of North China Plain, pot and field experiments were conducted. The results showed that N application improved growth of wheat, e.g. leaf area, specific leaf weight, total dry weight and grain yield were increased by 106%, 35%, 37% and 64%, respectively. Application of P increased total dry weight and grain yield by 12% and 17%. Application of N together with P could increase total dry weight and grain weight by 48% and 75%. However, application of K had no such effect. The WUE, calculated from the total dry weight and water consumed by the plant, was increased by 10.5%, 11.7%, 15.5% and 10.3% in the treatments of N, NP NK and NPK, respectively. With nitrogen application, the water potential of the leaf was increased about 0.2 MPa, chlorophyll content, CO2 assimilation and transpiration of the flag leaf were increased by 13–14%, 30–40% and 12–24%, respectively. With the increase of N applied, biomass, grain yield and WUE increased. However, this effect was reversed when the amount of nitrogen applied was higher than 100 kg/ha.