Plasmalemma alteration during cold acclimation of Hedera helix bark

Abstract

The transverse relaxation rate of water protons of nonacclimated Hedera helix L. cv. Thorndale (ivy) bark decreased in the presence of added extracellular Ca2+, Mg2+, or CO2. Evidence that the decreased transverse relaxation rate is due to decreased plasmalemma water permeability is presented. The decrease in plasmalemma water permeability induced by Ca2+ and CO2 was less in cold-acclimated ivy bark than in nonacclimated ivy bark, indicating that the process of cold acclimation altered a functional property of the plasmalemma. It is not known if the functional change in the plasmalemma is related to the degree of plant cold hardiness or is simply a low temperature response.