Pressure-Induced Water and Solute Flow Through Plant Roots

Abstract

Water and salt flows through detopped sunflower, tomato and red kidney bean roots under applied pressure were studied using a pressure chamber. Values of Jv for these root systems were measured applying variable pressure on the root medium, and Lp calculated. The K, Na and Cl fluxes under applied pressure were compared with those in intact plants at the same water flow rates. Ten to 100 times higher Na and Cl fluxes were observed through detopped roots under pressure as compared to those in the unpressurized, intact plants. It is suggested that the roots under pressure are not completely analogous to intact plant roots, and that pressure-induced flow may not be a reliable method of determining characteristics of ion flow in roots in relation to water flow.