Root-soil boundary zones as seen by the electron microscope

These micrographs show greatly enlarged views of the outer edges of root cells in contact with the soil. Of particular interest is the mucigel, a jelly-like coating on the outer surface of the roots. Mucigel, produced by the roots and perhaps also by microbes living in it, conforms to the surface contour of the soil particles it touches. Thus, intimate contact is provided for the transfer of soil nutrient ions and water from the soil to the roots.