Improving water and nutrient use efficiency of potato by partial root-zone drying irrigation in a semi-arid area in China: A field experimental study

Partial root-zone drying irrigation (PRD) has been established as an efficient technology to save water without sacrificing crop yield, but its effectiveness in saving nutrients and reducing the impact on soil and water environment is less well understood. In this paper, we present the results of a field experimental study with potatoes to demonstrate that PRD can save not only water but also nitrogen. It keeps soil water at 90% of the field capacity, alternately keeping half of the roots dry in both subsurface-drip and furrow PRD. The measurements of soil nitrogen after harvest revealed that the residual mineral nitrogen in the soil from 0 to 30cm deep reduced by 29.72% and 17.05% respectively under drip PRD and furrow PRD compared to the corresponding full irrigation. Similarly, for soil in depth from 30 to 60cm, these increases to 13.52% and 33.17% respectively under drip full irrigation and furrow full irrigation compared to the corresponding PRD irrigation. It indicates a significant decrease in nitrogen leaching when irrigated using drip PRD. © 2016, UK Simulation Society. All rights reserved.