Blog Post #6 Adison Akery

The Story of the Seed

The Brussel Sprouts Brief

By William Mahnke, Ben Buran, Chase Lyes, and Adison Akery

Abstract:

The purpose of this experiment is to see how the color of light affects a plant’s growth.  We hypothesise that red would be the most suitable and help the plant grow the most.

The experiment requires colored sheets,many pencils, soil, and wallaby yogurt containers are the pots.  A lot of water is used and you must build tents to create an environment for the plants.  The “red” plants manage to do very well, the other groups doing ok.  This could’ve been because it reproduces the color of the sun.  So whenever people are gardening, it’s important to use a color like the sun for light.

Introduction:

For our project, we were asked to create an experiment to either test the germination of seeds or the growth rate of plants.  We decided to test if the color of light a plant is receiving affects the growth rate of the plant.  The seeds we are using for the experiment are brussel sprout seeds, part of the brassica oleracea family.  Our hypothesis was, if the coloration of light affects the growth development of the plant, then the lighter the color of the light will help grow the plant more efficiently.  We predicted that the “hot” colors such as red, orange, and yellow, who benefit more than the “cool” colors like blue, green, and purple.

Materials:

• 12 number two pencils
• 8 wallaby yogurt containers
• 2 plastic sandwich bags
• Tape
• Tap Water
• Red and blue colored saran wrap sheets
• Wrap the red and blue sheets around the container and use the pencils to help create a tent like structure
• For purple, do the same with the red and blue containers, but combine the blue and red sheets together with tape

Experimental Procedure:

1. Fill each wallaby yogurt container to 7 cm of soil
2. Poke your finger into the cup half a centimeter to create a hole
3. Put two seeds in each hole and fill the hole again.
4. Tape two pencils on the exteriors of all eight cups.
5. For six cups wrap two in blue saran wrap, two in red saran wrap, and two in both red and blue wrap.
6. For the control groups, tape the plastic sandwich bag over the plant and cut holes in the bag so the two plants can respirate.
7. Water each plant with 10 milliliters of tap water using a syringe.
8. Place all 8 plants under fluorescent tubes
9. Wait until the next Monday, Tuesday, or Thursday to water the plants again with 10 mL of water.
10. Measure the plant three times a week in centimeters
11. Continue this process for four weeks

Results:

Week 1.

For our first check we saw no change in the growth of the plants because we had just watered and seeded the cups so we didn’t take any measurements for any plants in any group.

Week 2.

Still none of the experimental plants have sprouted, but the controlled cups have in fact grown about 1 centimeter. The group believes that the experimental plants will have a slower growth rate because the light rays will take longer to penetrate through the colored paper. In conclusion, we expect all of the plants to sprout in the following week and hope that the humid environment does not stop our plants growth.

Week 3.

It is Monday and the experimental seeds have just sprouted. The first red cup has grown to about 2 and a half centimeters, but the second red cup only grew about 1.2 centimeters. The first blue cup grew an astounding 3.8 centimeters, with the second blue cup growing a decent 2.2 centimeters. What the group has observed with the two controlled cups is that they have a more similar height than the experimental cups. Finally, the group has concluded this week that the experimental plants look like the humid environment has affected their height because opposed to the wider controlled plants, they are taller.

Week 4.

This week the plants are growing at a rapid rate. Both blue cups are about 4 centimeters tall and the controlled groups are both very similar still at a height of 3 centimeter tall. The red cups are a little more inconsistent, both only grew about .5 centimeters in the last week which does not make that much sense. Maybe red might be hard for the light to hit through. The purple paper at the moment is growing extremely slow, for they are only at 2.4 centimeters tall. The group speculates that this is because they are the only cups that are covered in two layers of saran wrap. Which means that light is having a harder time penetrating the wrap.

      

This graph was shown to compare the final height of each plant over the four weeks of our experiment.  As you can see, Red 1 was the tallest out of any plant, followed by Purple 1.

This graph was shown to compare the rate of growth over the four weeks.

Discussion:

The results of the experiment were very interesting.  The plants that received red light did extraordinarily well compared to any other group.  Every other group did as well as every other one.  So our hypothesis supported but definitely not correct.  The red did well because the plants that were receiving red light matched the color of the sun the best.  The purple also didn’t do that well because we realized halfway through that the purple was probably receiving less light than the other plants because the light had to go through two layers in order to reach the plant.  So in order to not have that problem, we would’ve used a purple sheet instead of combining two colors. Applying this to the real world, people should always grow things out of the way of the cool colors and replicate a light with hot colors to most replicate the sun.

Conclusion:

In conclusion, whenever you are to grow plants, your light source should be a color that replicates the sun.  Which would mean that cool colors are not the right coloration to grow your plants at a faster rate.