Influence of hydraulic conductance of xylem on water status in cuttings

Abstract

The reduction in water potential of cuttings after planting in water closely was related to an increase in resistance to water flow in the xylem. From observations of water-conducting tissues using a scanning electron microscope, the increase in resistance to water flow of cuttings was caused by blockage of vessel lumens with tyloses for Populuscarolinensis and aspiration of bordered pits for Cryptomeriajaponica. Water status of cuttings decreased with time after planting and was maintained at a low level by water absorption through bark. After rooting, the total resistance to water flow decreased and the water status of cuttings increased.