STUDIES ON PHOTOSYNTHESIS SOM~ EFfECtS OF LIGHT OF HIGH INTENSITY ON CHLO~1:LA* BY JACK MYERS AND G. O. BURR

I t is the purpose of this report to present quantitative data on some effects of high light intensities on Chlorella. No comparable data have as yet been published, although a number of workers, using various techniques, have studied the effects of intense light on the green plant. I t has been generally demonstrated that after long exposure of a plant to strong light there may be a disappearance of the products of photosynthesis (solarization), a decrease in the apparent rate of photosynthesis, or microscopically observable injury to the tissue. In this paper the term solarization will be used to indicate a reduction in photosynthetic rate due to prolonged exposure to light. The literature has been reviewed in the more recent work of Emerson (1935), Fockler (1938), Hohnan (1930), and St~lfelt (1939) and need not be considered in detail here. Most of the work has dealt qualitatively either with the ecological aspects of the problem or with the mechanism by which the observed effects might be brought about. The data to be presented in this paper describe the solarization effect as a function of light intensity and time.