Nocturnal versus diurnal CO2 uptake : how flexible is Agave angustifolia?

© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Bibliographische Detailangaben
Veröffentlicht in:Journal of experimental botany. - 1985. - 65(2014), 13 vom: 21. Juli, Seite 3695-703
1. Verfasser: Winter, Klaus (VerfasserIn)
Weitere Verfasser: Garcia, Milton, Holtum, Joseph A M
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2014
Zugriff auf das übergeordnete Werk:Journal of experimental botany
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Agave C3 photosynthesis CO2 response biofuel climate change crassulacean acid metabolism drought stress temperature response. mehr... Biofuels Water 059QF0KO0R Carbon Dioxide 142M471B3J
Beschreibung
Zusammenfassung:© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Agaves exhibit the water-conserving crassulacean acid metabolism (CAM) photosynthetic pathway. Some species are potential biofuel feedstocks because they are highly productive in seasonally dry landscapes. In plants with CAM, high growth rates are often believed to be associated with a significant contribution of C3 photosynthesis to total carbon gain when conditions are favourable. There has even been a report of a shift from CAM to C3 in response to overwatering a species of Agave. We investigated whether C3 photosynthesis can contribute substantially to carbon uptake and growth in young and mature Agave angustifolia collected from its natural habitat in Panama. In well-watered plants, CO2 uptake in the dark contributed about 75% of daily carbon gain. This day/night pattern of CO2 exchange was highly conserved under a range of environmental conditions and was insensitive to intensive watering. Elevated CO2 (800 ppm) stimulated CO2 fixation predominantly in the light. Exposure to CO2-free air at night markedly enhanced CO2 uptake during the following light period, but CO2 exchange rapidly reverted to its standard pattern when CO2 was supplied during the subsequent 24h. Although A. angustifolia consistently engages in CAM as its principal photosynthetic pathway, its relatively limited photosynthetic plasticity does not preclude it from occupying a range of habitats, from relatively mesic tropical environments in Panama to drier habitats in Mexico
Beschreibung:Date Completed 26.02.2015
Date Revised 21.03.2024
published: Print-Electronic
Citation Status MEDLINE
ISSN:1460-2431
DOI:10.1093/jxb/eru097