WHEN REDS & BLUES COLLIDE
The same NFT channel under several different light treatments.
RED LIGHT
The majority of the light plants
are exposed to is red light. In fact,
chlorophyll is most efficient at
absorbing light with wavelengths
around 660 nm, which is solidly in
the red range (650-730 nm) of the
spectrum. The light that chlorophyll
absorbs primarily drives the synthesis
of compounds used for energy and
building materials within plant cells.
However, overexposure to red light
can have detrimental effects on
plants. When red light intensities are
too high, chlorophyll synthesis may
become suppressed. Leaves lacking
chlorophyll will have a bleachedwhite appearance, since chlorophyll
is responsible for the green color of
leaves. Beyond overexposure, the
exclusive use of red light can also lead
to interesting and often unwanted
physiological changes. Leaves and
stems in plants grown under red light
alone become elongated, and flower
initiation in some species can be
extremely delayed.
Far-red light between 730 and 770 nm
also plays an important role in plant
development. Increased amounts of
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Maximum Yield USA | October 2015
“Over the past
several decades,
researchers have
been able to isolate
other light-sensing
compounds within
many plants, and
identify what kind of
light they are most
responsive to.”
far-red light typically indicate a shaded
environment. Phytochromes give the
plant a way to sense relative ratios
of red and far-red light. When this
shading effect is detected, physiological changes are triggered that lead to
the stretching of plant leaves and