THE FUNCTION OF PHYTOCHROME IN THE NATURAL ENVIRONMENT—II. THE INFLUENCE OF VEGETATION CANOPIES ON THE SPECTRAL ENERGY DISTRIBUTION OF NATURAL DAYLIGHT

摘要: Abstract— Qualitative changes in the spectral energy distribution (SED) of natural daylight within 400–800 nm wavelength band have been followed a wheat canopy. Selective attenuation radiation by canopy caused large decreases blue and red wavebands and, to lesser extent, green; far-red was largely transmitted. This resulted decrease red:far-red ratio from values observed daylight. The below found be partially dependent on solar elevation sky condition; it also age, height, leaf area index chlorophyll content crop. The possible ecological significance wide variety distributions which are discussed relation phytochrome function.