|
The mechanisms controlling the photosynthetic performance of C4 plants at low temperature were investigated using ecotypes of Bouteloua gracilis Lag. from high (3000 m) and low (1500 m) elevation sites in the Rocky Mountains of Colorado. Plants were grown in controlled-environment cabinets at a photon flux density of 700 μmol m−2 s−1 and day/night temperatures of 26/16 °C or 14/7 °C. The thermal response of the net CO2 assimilation rate (A) was evaluated using leaf gas-exchange analysis and activity assays of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEPCase) and pyruvate,orthophosphate dikinase (PPDK). In both ecotypes, a reduction in measurement temperature...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Bouteloua,
C4 photosynthesis,
Plant, Cell & Environment,
Rubisco activity,
gas exchange, All tags...
photosynthesis,
sub-alpine plants,
temperature responses, Fewer tags
|
Shrubs of the Great Basin desert in Utah are subjected to a prolonged summer drought. One potential consequence of drought is a reduced water transport capability of the xylem. This is due to drought-induced cavitation. We used the centrifuge method to measure the vulnerability of root and stem xylem to cavitation in six native shrub species. The shrubs fall into three categories with regards to rooting depth, vegetative phenology and plant water status during drought. The “summer green� group (Chrysothamnus viscidiflorus, Atriplex canescens, Atriplex confertifolia) sustains summer drought with a relatively shallow root system (<2.5 m), but maintains leaf area. A “drought deciduous� group (Grayia spinosa,...
|
|