- 1) Institut für Botanik, Universität Innsbruck, Sternwartestrasse 15, A-6020, Innsbruck, Austria
- 2) Department of Botany, University of Cambridge, Downing Street, CB2 3EA, Cambridge, UK
The dynamics of leaf extension in five species of Poa were studied with electronic auxanometers (LVDTs) along an elevational gradient from 600 to 3200 m in the Austrian Alps. Extension rates peak at midday at all elevations and rates at 20°C are almost twice as high at low elevation as compared with those from the highest sites. The low temperature threshold for leaf extension drops by 7 K over this range of elevation, with plants from the highest sites showing some extension around freezing point. Thus, there is a substantial adaptive adjustment in response of leaf extension to declining mean temperatures with increasing altitude, which is not paralleled by known altitudinal trends of photosynthetic responses in herbaceous plants.
- 1 - sciences appliquees, technologies et medecines
- 2 - sciences biologiques et medicales
- 3 - sciences biologiques fondamentales et appliquees. psychologie
- 1 - Life Sciences ; 2 - Agricultural and Biological Sciences ; 3 - Ecology, Evolution, Behavior and Systematics