Wavelengths of radiation (mostly reds and some blues and yellows) used by plants for photosynthesis (production of sugars).
the quantity of visible wavelength light in the 400-700nm range whose energy is available for photosynthesis
Light in a specific wavelength range that is useable by plants for photosynthesis. This light range is from 400nm-700nm, and is part of the visible light spectrum. While receiving light in this range, plants are most efficient in their production of energy through photosynthesis.
Those wavelengths in the spectrum of radiation that are effective in photosynthesis.
Radiation with wavelengths ranging from 400 to 700 nanometers (0.4 to 0.7 micrometers) used by green vegetation in the photosynthetic process.
Energy from the visible range of solar radiation, (400 – 800 nm), the wavelengths most active in photosynthesis.
(Abbreviated PAR.) The electromagnetic energy in the 400– 700 nm wavelength range. Measured as the photosynthetic photon flux (PPF) in quanta per second per square meter, or mole of quanta per second per square meter, or photosynthetic irradiance (PI) in watts per square meter for the specified wavelength band.
The expression Photosynthetically Active Radiation, often abbreviated PAR, designates the spectral range of solar light from 400 to 700 nanometers that is useful to terrestrial plants in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to be so energetic that they can be damaging to cells and tissues; fortunately they are mostly filtered out by the ozone layer in the stratosphere.