CHLOROPHYLL FLUORESCENCE AND ANTHOCYANIN CONTENT IN CHILLED MAIZE PLANTS AFTER RETURN TO A NON-CHILLING TEMPERATURE UNDER VARIOUS IRRADIANCES

The effect of irradiance on the ratio of variable to maximum fluoresce nce (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 gr own throughout at 25 degrees C in the light, the F-v/F-m hardly change d during chilling or when returned to a non-chilling temperature in th e 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 eith er at low temperature or after transfer to 25 degrees C in the dark. H owever, there was a sudden increase in the anthocyanin level after ret urning the plants from dark cold conditions to a non-chilling temperat ure in the light.