The effect of irradiance on the ratio of variable to maximum fluorescence (F-v/F-m) and on the anthocyanin content of chilled (0.5 degrees C) young maize plants was investigated after returning the plants to a non-chilling temperature (25 degrees C). Compared to control plants grown throughout at 25 degrees C in the light, the F-v/F-m hardly changed during chilling or when returned to a non-chilling temperature in the dark, but there was a decrease in this parameter if the plants were shifted to the light after the cold treatment. Similarly, compared to the control plants there was no change in the anthocyanin content either at low temperature or after transfer to 25 degrees C in the dark. However, there was a sudden increase in the anthocyanin level after returning the plants from dark cold conditions to a non-chilling temperature in the light.
