Materials

For the Kohlrabi Germination experiment, the following materials are needed:

• A scale
• Paper towel
• Water
• Approximately 300 kohlrabi seeds
• A waterproof marker
• A fridge
• A heat mat
• A ruler
• A pencil
• Paper
• 3 trays (one for each set of seeds)
• A camera
• 3 plastic bags

Procedure

1.      Place the given container on the scale, and zero it to ensure precise weight measurements.

2.      Place approximately 100 untreated Kohlrabi seeds into the container that was used to originally zero the scale. Then add or take out seeds until the scale reads 0.4 grams. You may not need to add or take out seeds.

3.      Repeat the process mentioned in "Step 2", 2 more times after the first so you have a total of three sets of seeds that weigh 0.4 grams each.

4.      Take 3 pieces of paper towel and cut each to the following dimension: 8”x12”.

5.      Use a Lumocolour permanent waterproof marker, (to insure the ink will not bleed), and write your group name. Along with that write the temperature type, (heating mat temp., fridge temp. or room temp.) on one half of the paper towel.

6.      Hold each individual paper towel piece under warm running tap water one at a time, until the paper towel is moist.

7.      On each piece of the moistened paper towel, place one of the three 0.4 grams sets of Kohlrabi seeds evenly. They should cover only one half of the paper towel, (the opposite side should have your group name on it as mentioned in "Step 5").

8.      Fold the paper towel half without Kohlrabi seeds on it on top of the half with the seeds so that the group name can be seen on top.

9.      Fold over the edges of the paper towel to ensure that the seeds will not spill out.

10.  Place the seed filled paper towels in their designated areas.

11.  Record any and all observations daily.

 Independent Variables

   The Independent Variable is the variable that stays unchanged throughout the experiment and is not influenced or changed by the dependent variable at any time during the experiment. The individual doing the experiment is in control of this variable.
1. Temperatures

• Room Temperature
• Heat Mat Temperature
• Refrigerator Temperature

Dependent Variable

   The dependent variable is the variable who's results are influenced by the independent variable, and change over the course of the experiment. It is the variable that has the potential to change over the course of the experiment, and is what the people who are conducting the experiment use to either support or not support their hypothesis.

 1. Kohlrabi Seeds

• Set 1
• Set 2
• Set 3

Control Variable

   The variables and factors that remain the same between the different sets of the dependent variable. This variable allows the experiment to be as real as possible because all sets of the dependent variable are identical, so no differences can change the outcome of the experiment. 

1. Factors that remain identical between all three sets of the dependent variable.

• Amount of time Kohlrabi seeds are exposed to the temperatures.
• Size of paper towel used to enclose the Kohlrabi seeds. 
• Type of seeds used (Kohlrabi, untreated)

Control Group

A set of the dependent variable that is identical to the ones being tested, but is not tested so that the results between the other sets can be compared with an original and untested set and conclusions can be made.  



 1. The control group is none existent; instead, the results will be compared using all
three of the sets of the dependent variable.

Daily Journal

February 18:

Today we set up the blog, and assigned different roles to the members in our group. Ajeet is the blogger, Lauren is the journalist, Alexa is doing the experiments and Viney is a little bit of all three!

February 19:

Today we went through the actual process of doing the experiment. For details, look under "Procedure" to see exactly what was done today. For this experiment, our group was designated to use untreated kohlrabi seeds.

February 21:

Today was the first time we observed the seeds. There were no problems and everything happened as we had planned it to.

Day 1 - Room Temperature Seeds

•  The paper towel was damp
• 28 of the approximately 100 seeds showed no signs of sprouting.
• The visible sprouts measured an average of 2 mm.

 





  

Day 1 - Heat Mat Temperature Seeds

• The paper towel is completely dry on one side, and slightly damp on the other
• 15 of the approximately 100 seeds showed no signs of sprouting.
• The visible sprouts measured an average of 1.5 cm.
• The roots began forming, looking almost transparent, fuzzy, and fluffy.
• Some roots were attached to the paper towel.

 

 

 

Day 1 - Fridge Temperature Seeds

• The paper towel was very wet, ( there was more moisture in it now than it initially started with).
• There were no seeds that showed any sign of sprouting.

 

February 25:

 

Today we observed the Kohlrabi for the last time. We then chose certain sprouts we wished to examine underneath the microscope. Here are some pictures of us observing the Kohlrabi sprouts:



                   

Day 2 (Final day) - Room Temperature Seeds

 

• Every seed sprouted; although, many died because they did not recieve enough water.
• The seeds that survived were all very dry and discoloured (yellow).
• Many had a brown lining around the edge of each leaf.
• The roots were attached to the paper towel.
• The paper towel was very dry and the seeds that survived best were only in the damp areas.
• The average length of sprouts is 4.5 cm long.
• All seeds showed Dicots.

Day 2 (Final day) - Heat Mat Temperature Seeds (32 degrees celcius)

 

• Only 21 seeds survived.
• The dead seeds were in areas where the paper towel was dried up.
• The roots of the living seeds were attached to the paper towel.
• The average length of the living sprouts was 6 cm long.
• The paper towel was damp, with only a few dry areas.
• The living sprouts were a yellow-green mixture in terms of colour.
• There were two moldy seeds. One had a dark mold, the other had a white mold.

Day 2 (Final day) - Fridge Temperature Seeds (4 degrees celcius)

 

• Two seeds showed a small sign of life.
• There was a very small slit of green in these two seeds.
• The paper towel was very wet.

Observations using a microscope:

We decided to take a moldy seed from the heat mat temperature paper towel and observe it under the microscope. We found that the moldy seed was covered with a lot of strands of grey/black fuzz with little round dots on the end of each strand. On each strand and dot there were miniscule strands of fuzz sticking straight up.

We also observed an unhealthy leaf and a healthy leaf.

The unhealthy leaf showed a brown line, that was very thin, silhouetting the leaves. It appeared that the inside of the seed shell was orange, as shown in the picture below. The roots in this microscope view are white/transparent and fuzzy with a shadow of darkness defining the texture. The roots were kinky, and irregularly shaped.

 

We next observed a healthy leaf. The healthy leaf was green in colour, with much texture within the leaf. The texture appeared to be like a grid of streaks covering the surface of the leaf. There was not a brown lining on the outside of the leaf, like there was with the unhealthy leaf.  The green colour gradually faded into the white colour of the sprout. Here is an image of the healthy leaf:

 

 

 

 

 

 

 

 

 



Discussion

          The Kohlrabi Germination Experiment taught us a lot about the conditions necessary to best grow the Kohlrabi seeds. We found that our hypothesis, which stated that the Kohlrabi seeds would grow best while in the Heat Mat temperature conditions, was correct and that the Kohlrabi seeds did in fact grow much quicker they did in the other two temperature conditions. Heat is a large component, when it comes to Kohlrabi seed germination and seed germination in general, because it provides the necessary push the enzymes within the seeds need to function. Without functioning enzymes the seeds would not grow, which explains why the seeds in the fridge temperature conditions did not grow almost at all.

          A few problems were encountered throughout the Kohlrabi germination experiment process. Although the seeds placed in the heat mat conditions grew much more efficiently and quickly compared to the others, the majority of them ended up dying. This is because our group's set of seeds was placed too close to the heating mat, (at the bottom of the pile), which caused the seeds to have too much heat exposure. The warm temperature caused parts of the paper towel to dry up, leaving limited moist sections. This disrupted and altered the total possible amount the Kohlrabi seeds could have germinated. To overcome this issue, it is necessary to experiment with the different possible distances that the seed sets can be placed at in relation to the heat mat. By doing this, the prime distance between the seeds and the heat mat can be determined, allowing you to ensure that the seeds will grow in the perfect conditions.

Conclusion

          After observing and comparing the germination rate of Kohlrabi seeds at room temperature, fridge temperature, and heat mat temperature, it was found that the germination rate of the seeds is fastest when using heat mat conditions. Although only 21 seeds survived at the end of the experiment, they each grew significantly faster than the ones placed in room or fridge temperature conditions. The average length of the sprouts grown with the heat mat after 5 days was 6 cm long, compared to the average length of the sprouts grown at room temperature, which was 4.5 cm long. There was close to no growth at all for the seeds that were grown in the fridge temperature conditions, as only 2 seeds showed signs of life at the end of the experiment. It was determined that the Kohlrabi seeds that grew using the heat mat temperature grew at an average rate of 1.2cm/day, whereas the room temperature seeds grew at an average rate of 0.9 cm/day. This evidence proves that the Kohlrabi seeds grown using the heat mat temperature had the fastest germination rate among the three different temperature conditions used.

Plant Lab

Biology 11: Plant Lab

Test #1: Compare germination rate of Kholarabi seeds at three different temperatures:

Room temp, heat mat temp, fridge temp

Design a Scientific experiment

Research Questions that need to be answered prior to designing experiment – what is kohlrabi (subspecies: superschmeltz), Scientific classification (Kingdom to species), Nutritional value, growth parameters (light, soil type, temp, humidity, size of plant, length of time to harvest), phototropism, anatomy of a seed, cotyledon significance and how many does kohlrabi have, method used to sprout seeds.

Hypothesis – define and state for your experiment. What is your best guess about what will happen

Materials – identification on all items and materials used

Procedure – Define the following – dependent and independent variables, control variables, groups and individuals

Data – what variables are you measuring, how often: time to germinate, rate of growth of cotyledon

Discussion – State whether your hypothesis was correct, partially correct, or incorrect. Re-approach and suggest a better hypothesis if new evidence came out of your experiment. E.g. heated mat may be the fastest germination rates but does it bring its own problems of fungus growth. Discuss any difficulties and suggest methods to overcome.

Conclusion – one or two sentences summarizing your findings.

Assessment

·         Student have used resources to answer research questions

·         A daily journal of activities and data

·         Developed each part of the experiment

·         Documented with photos labeled to show results

·         Present your information in a Gmail blog…