Etiolation (Tove)

Research Question and Hypothesis

What is the effect of light deprivation on radish height?

My hypothesis is that the radishes that are grown in a dark (0 lux) environment will be taller than those that are grown in a east facing window (120 lux), or those that are grown in a south facing window (6.5 lux).

Standards

Experimental Design

I grew three different types of radishes in three different rooms of my home where the light level was very different. All plants were grown in the same types of containers/medium. Each of the three types of radishes was grown in 4 pellets in each set-up. All three radish varieties were from Renee's Seeds. Radish A was rainbow radishes. Radish B was round radishes. Radish C was round red radishes. I taped a 1/2 centimeter graph paper behind each set-up, and marked every 2 centimeters. I took pictures daily. I used my cell phone for the light pictures, and I used my Birdcam for the dark pictures. Once many of the radishes started to fall over, I stopped the experiment. Throughout the experiment I added water as necessary. No fertilizer was added to any of the three set-ups.

Independent variable

The independent variable is the amount of ambient light. I measured the independent variable by using the luxmeter application on my cell phone.

Dependent variables

The dependent variable is height. I will have a grid design hanging over the radishes so that I can measure the height of the radishes from the time-lapse pictures.

Series

I will be comparing the height of the radishes as a function of time in 3 different light levels (120 lux, 6.5 lux, and 0 lux).

Constants and Controls

My constant is: the same variation of light during the course of the day

My controls are: I will be using the same type of growing medium as well as the same three types of radishes, and the same temperatures.

Materials

Materials:

Jiffy Windowsill Greenhouses - Home Depot

Rainbow radishes, Round radishes, Round red radishes - Renee's Garden Seeds

Bird Camera - Home Depot

Water

Procedures

1. Set up windowsill greenhouses per manufacturer sepecifications

2. Plant the three different types of radish seeds in a 2x2 grid. A=rainbow radishes, B=round radishes, and C=round red radishes

3. Take time lapse photos daily in all three environments.

Sample data and graphs

Here is a graph of what happened with the radishes.

Here is a link to the raw data. This data was averaged to create the graph.

Analysis & Conclusions

Analyze the data and draw conclusions relevant to your research question and hypothesis.

Photos & Movies

References

https://en.wikipedia.org/wiki/Etiolation

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Etiolation.html

http://www.hort.cornell.edu/uhi/research/articles/HortSci%2022(5).pdf