Effects of LED and Fluorescent Lights on Growth of Arabidopsis
Kevin O’Quinn, Mesha Arant, Jordan Ball, and T.J. White
Department of Biology, Wofford College, Spartanburg, SC 29303
Introduction
Different types of lights have been used to
increase the growth of various plants. Our
experiment tested whether LED or fluorescent
lights produce plants with larger root length
and higher germination rates. Fluorescent
lights, which emit heat, some noise, and
consume more energy, and use light that is
not as concentrated as the light of the LED
lights. LED lights use about 10% of the
energy of fluorescent lights, are a more
concentrated light source, and can last for a
significant number of years more than the
fluorescent lights.
Results and Findings
Root Length of Plants under Fluorescent and LED lights
Hypothesis
LED growing plates will allow the plants to
grow quicker and larger. The percent
germinated will be greater under the LED
growing lights rather than underneath the
florescent lights.
Plants that were grown under LED lights
(n=24) had smaller root lengths than plants
that were grown under fluorescent light
(n=24). The germination rate, not shown,
was not statistically relevant (Chi-square
(dF=1)=0.137; p=.712). After looking at the
growth rate from Week 1to Week 2, we found,
using a variable-selection procedure and
found that root length yielded the best results.
Analyzing the variable using Fdf=1,36=11.8;
p=.002. with this we concluded that the
Fluorescent lights grew the roots of the
Arabidopsis longer than the LED light panel.
Status of Hypothesis
LED growing plates did not produce
plants with longer root lengths nor higher
germination rates.
Materials and Methods
Discussion
Materials
•48 Arabidopsis seeds
•Growing Plates
•Fluorescent Growing Lights and LED
Growing Plates
•Agar
•Pipettes
•Tape
Methods
0.8% Agar was placed into 6 growing plates
and were left to set. Three plates were
designated for the LED lights, and three were
designated for the fluorescent lights.
8 seeds were placed in each growing plate.
The plates were sealed and placed in a vertical
position under the LED and Fluorescent lights.
The distance from the lights to the plants was
33.65cm.
They were maintained with a photoperiod of
16 hours of light and 8 hours of darkness each
day. Germination rates and root length were
measured each week of the experiment.
Explanation of Graph
The chart shows the average growth of the roots of the two treatment
groups. Along the x-axis is the treatment while on the y-axis is the length
it grew. The circles show the average length while the error bars show
95% confidence intervals.
Our experiment showed that fluorescent
lights produced plants with longer roots
than the LED light panel. The size of the
roots that were grown by the Fluorescent
lights had a considerable size advantage
over the LED lights. Of course, one of the
drawbacks of the Fluorescent lights is that
they require a lot more energy to work
than the LED’s. The LED’s use only about
10% of the energy of the Fluorescent. One
of the things that might have affected the
results was the height from the light source
to the plants. Because the LED panel
consisted of blue and red diodes, the
chance that moving it either closer or
farther from the plants may have
optimized the productivity of the light
panel. Either way, in this experiment, the
Fluorescent lights grew the roots longer
than the LED light panel.