Photoperiodic regulation of the seasonal pattern of photosynthetic capacity and the implications for carbon cycling.

ABSTRACT: Although temperature is an important driver of seasonal changes in photosynthetic physiology, photoperiod also regulates leaf activity. Climate change will extend growing seasons if temperature cues predominate, but photoperiod-controlled species will show limited responsiveness to warming. We show that photoperiod explains more seasonal variation in photosynthetic activity across 23 tree species than temperature. Although leaves remain green, photosynthetic capacity peaks just after summer solstice and declines with decreasing photoperiod, before air temperatures peak. In support of these findings, saplings grown at constant temperature but exposed to an extended photoperiod maintained high photosynthetic capacity, but photosynthetic activity declined in saplings experiencing a naturally

SUBMITTER: Bauerle WL 

PROVIDER: S-EPMC3365212 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature