Lateral Movement of Inorganic Solutes in Plants

Abstract

PREVIOUS work in inorganic solute movement in plants has suggested that the minerals follow a specific polar path from the roots which absorb them to the leaves in which they are deposited^1,2. Recently, evidence supporting polar transport has been provided by Caldwell using a split root technique³. It was established that when the root systems were placed half in rich loam and half in sand the nutrient status of the two halves was reflected in the development of the foliage directly above. This result was interpreted as a polar movement of nutrients. However, the important issue is not whether polar movement can occur, but whether it must occur, owing to the absence of lateral transport systems.