Root System Response to Drought and Salinity: Root Distribution and Water Transport

Abstract

Plant responses to water stress and salinity have been widely discussed in many species. The growth of stressed plants is often limited by the ability of roots to extract water from the soil and transport it to the shoot, which determines the concentration of substances reaching the aerial part. In spite of this, little work has been done in connection with roots as regards salt or water stress. Although roots might seem the most vulnerable part of the plant, since they are directly exposed to salt or to drying soil, the intensity of the root system response may vary according to the species, the level and duration of the stress and cultivation conditions. For example, roots growing in pots are more affected by environmental conditions in the substrateroot complex than they would be with ground cultivation. This work reviews the recent literature on root system responses in ornamental species grown in containers and woody trees growing in soil exposed to deficit irrigation strategies and alternative irrigation sources (brackish, reclaimed). The aim is to extend our understanding of how these conditions may affect the characteristics and activity of roots, especially the water absorption capacity.