Figure 1

Freezing damage in Arabidopsis leaves visualized by chlorophyll fluorescence imaging. The panels show false color images of the chlorophyll fluorescence yield (FV/FM) of detached leaves from the accessions C24 (A) and Te (B) after freezing to the indicated temperatures at 2°C/h and slow thawing on ice. Plants were harvested either directly from a greenhouse under nonacclimating conditions (NA), or after an additional 14 days of cold acclimation at 4°C (ACC).