Growth, Water Relations and Yield of Wheat

Abstract

Two crops of Sherpa wheat grown in successive years, but under contrasting seasonal conditions, were subjected to comprehensive environmental and biological measurement. An analysis is made of the changing state of water in the soil-plant system and of the consequent growth and the development of grain yield. The early pattern of growth was strongly influenced by moderate restriction in the availability of soil water (> - 200 J kg ^-1) and was associated with a marked shift in the allocation of growth resources in favour of root development. In both years, but more so in the second, grain filling proceeded under rapidly increasing plant water stress and senescence of productive photosynthesizing area. An analysis of the quantitative consistency of the biological and environmental data is attempted by the application of a published model of crop growth to the experimental data.