Photosynthesis Under Field Conditions. IV. Light Studies with Individual Corn Leaves 1

The shape of the light response curve of individual leaves has recently become important in models for light absorption by field crops. Studies of the light response of individual corn leaves under sunlight is discussed. A leaf chamber technique for the continuous measurement of net assimilation of CO/sub 2/ by a leaf or corn ear was developed. Uptake rates of corn leaves under optimum light were of the order of 45 mg. of CO/sub 2/ per square decimeter leaf area per hour. Corn ear temperature and percent dry matter were found to have a marked effect on the respiration rate. Corn ear husks photosynthesized approximately 30 mg. CO/sub 2/ per ear per hour under midday sun. 20 references, 5 figures, 3 tables.