Changes in Catalase Activity and Other Responses Induced in Plants by Red and Blue Light

Abstract

Changes in catalase activity in plants, caused by irradiation for short periods of time with red or blue light, were studied. It was found that in etiolated barley seedlings and other grains, catalase activity is greatly depressed by blue light and elevated by red light. This is also true for young tomato and tobacco plants grown in normal daylight and illuminated with colored light for 3 to 6 days. Catalase in legumes (beans, peas, clover) was increased by irradiation with blue light and decreased by red light. Chloroplasts from red irradiated plants were found to be 60 to 70% less efficient in the Hill reaction than those from blue irradiated plants. Quantitative differences caused by red or blue light were observed in ascorbic acid and protein content. The probable significance of catalase in bio-synthetic processes is discussed.