RESEARCH ON THE REGULATION OF WATER AND FERTILIZERS AND A CROP GROWTH-MODEL OF SPRING WHEAT IN FARMLAND OF SEMIARID REGIONS

Based on the results of experiments on the regulation of water and fer tilizers to spring wheat in farmland of semi-arid regions, the paper d iscusses optimum matching of water and fertilizers from the point of v iew of farmland ecology and studies the dynamic laws of leaf area, lea f area index and the value of leaf area duration of spring wheat with different amounts of water and fertilizers. It establishes the growth model of spring wheat and a statistical model between the integral of leaf area and the yield, and analyzes quantitatively the relationship between the coefficient of minimum water consumption and the optimum a mount of fertilizer. The results are important for utilizing the limit ed precipitation resources and high efficient yield of spring wheat in semi-arid regions. (C) 1998 Elsevier Science B.V. All rights reserved .