abstract: The halophytic species Mesembryanthemum crystallinum was induced to exhibit CAM-like CO2gas-exchange reactions with a depression of net CO2uptake during the day and a net CO2uptake during the night by treatment with 400 mM NaCl. The induction of CAM is favored by relatively high day temperatures and relatively low night temperatures. Net CO2uptake in the dark is largely increased by an interruption of water absorption by the plants, whereas light CO2fixation is decreased by this treatment. When plants are rewatered after a two days drought period, net CO2uptake in the dark is clearly favored over CO2light fixation. During the post-stress period a slight reduction of leaf chlorophyll content becomes apparent. Under the experimental conditions used a reversibility of CO2fixation metabolism from CAM to C3is observed when salt-treated plants are transferred to non-saline root medium. This is paralleled by a largely enhanced leaf expansion and a drastically increased leaf water content.
authors.affiliation: Fachbereich Biologie der Technischen Hochschule Darmstadt, Darmstadt, Deutschland.
authors.forename: Klaus
authors.initials: K
authors.lastname: Winter