Root pressure contributes to water transport in plants, particularly during the night when transpiration rates are low. It involves the active pumping of water into the xylem by root cells, creating pressure that pushes water upward.
What is the role of root pressure in water transport, and when is it most significant?
Share
Root pressure is the force that helps drive water upwards in the xylem of plants, primarily in non-woody, herbaceous plants. It results from the active transport of minerals into the root cells, creating a higher solute concentration in the roots. Water moves into the roots through osmosis, generating positive pressure. Root pressure is most significant during periods of active water uptake, such as at night or in the early morning, when transpiration is low. It contributes to guttation, the exudation of water droplets from leaf margins. However, it’s generally insufficient to account for the long-distance transport of water in tall plants.