Plant Factors and Opportunities for the Improvement of Root Functioning

Keywords: Water and nutrient use efficiency, Plasmamembrane, transporters, Nitrogen sensing, Signalling, Root morphology.

Plants get most of their nutrient and water requirements from the soil and although there are still some surprising gaps in our understanding, we have a good general appreciation of how this is achieved. It is now possible to use new genetic tools to identify the molecular and cellular basis of the regulation of water and ion uptake by roots. The identification of genes involved in ion and water uptake at the membrane level and in the modification of root growth and morphology in response to water and nutrient stress will provide us with new ways of maximising water and nutrient use efficiency in agriculture. We highlight recent developments in root cell biology and recent increases in understanding of root functioning under stress that might be exploited in the future for the benefit of agriculture and the environment.

This paper describes the movement of water and nutrients through the soil to the root surface, their uptake across the root into the xylem and their flux though the xylem to the leaves. Limitations to nutrient and water uptake and distribution are described and some opportunities for the manipulation of uptake are identified. We consider the possibility of optimising the water and nutrient use efficiency of the plant and enhancing plant growth in water limited environments.

W. J. Davies and C. Dobson, Lancaster Environment Centre, Lancaster University, Lancaster, UK

T. Rados-Blanusa, HRI, East Malling, Kent, UK

16 pages, 3 figures, 31 refs.