Abstract
Dark CO 2 fixation and δ 13C values were measured in 27 species of the 3 sub-families of Bromeliaceae. 13 species were in a group with a mean δ 13C value of −12.9±1.2% and with dark CO 2 fixation and 14 species in another group with a mean of −25.3±1.8% 0 . With the exception of Guzmania monostachia, all species showing dark CO 2 fixation, measured colorimetrically or as malate accumulation, had δ 13C values of a C 4 type i.e. showing the least amount of isotope discrimination. These results are consistent with the interpretation that δ 13C values in CAM plants indicate the proportion of the carbon in the plant that entered by either of the two photosynthetic carbon cycles and the degree of ‘openness’ of the ribulose diphosphate (RuDP) carboxylase reaction. The ecological significance of CAM metabolism is indicated by the evidence that species showing net dark CO 2 fixation came from dry epiphytic or terrestrial habitats.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
