Kohlrabi Reasearch Questions

What is Kohlrabi?

          Kohlrabi is a Cruciferous plant, that is a part of the nutrient packed Brassicaceae family. It is a vegetable that shares common characteristics with other vegetables such as cabbage and cauliflower, who are also a part of the family. The Kohlrabi has two colours, green and purple, and it is shaped like a slightly flattened ball while a couple stalks come out of one of its sides. Kohlrabi is also a perennial vegetable, meaning it survives throughout the year and its seasons, and it can last for several more years after the first. It is very high in nutrition and is good for the immune system.

Superschmelz Kohlrabi

            Superschmelz Kohlrabi is a subspecies of the Cruciferous plant Kohlrabi. It is a giant version of the Kohlrabi and it can grow to massive sizes. The bulb of the plant can reach lengths of 10 inches, and it can reach weights over ten pounds. The makeup of the vegetable is the same as the original Kohlrabi, but the size and quality of it is very different. It is well known for its flavourful taste and tenderness.

Kohlrabi Taxonomy

1. Kingdom: Plantae

   Kohlrabi is a part of the Kingdom Plantae, which is the kingdom made up of self nourishing organisms that undergo photosynthesis and contain a special green pigment, chlorophyll, which allows photosynthesis to occur. Organisms within this kingdom are also almost always green in some way, and they have a cell wall surrounding every individual cell, which allows them to be strong and gives them shape.

2. Phylum: Anthophyta
   
       Kohlrabi is in the phylum known as Anthophyta. All organism within this phylum have the same body plan and structure and they are all also angiosperms, (flowering plants). The plants seeds are created within the ovaries of each organism.
3. Class: Eudicotyledones
   
       Kohlrabi is in a class with organisms known as Eudicotyledones. These organisms are flowering plants that have two cotyledons. Leaves with netlike veins which stem from one main vein are exclusive to this group. Eudicots are also the only organisms to have multiple flower parts, which usually varies between four and five.
4. Order: Brassicales
   
      Kohlrabi is a part of the Brassicales order. All members of this order are genetically, chemically and structurally similar to one another. They are also the only order that has organisms who produce Glucosinolate, which is mustard oil.
5. Family: Brassicaceae
   
      Kohlrabi is a member of the Brassicaceae family. Organisms in this family usually have four flower petals, and they form like a cross. These plants also have flower clusters located around them.
6. Genus: Brassica
   
       Kohlrabi is in the Brassica Genus. The organisms in this Genus are edible, and they are usually vegetables as well as plants. They are all related to mustard and cabbage plant, and they are Cruciferous, which means they have flowers that form in the shape of a cross
   .
7. Species: Brassica Oleracea    
   
      Kohlrabi is a part of the species known a Brassica Oleracea. This species includes all wild flower and they are all biennial, which means it takes two years for the organisms in this species to complete their full life cycle. These plants are rich in Vitamin C and other nutrients and they also form large fleshy and thick leaves, which grow nicely around the stem. They are also very specialized, and they have adapted so they can store a lot of water and nutrients when they are in tough environments. In their final year of life, they will also grow a spike, which then holds a yellow flower.

                                                           

Nutritional Value
  Per one serving  (135g)

• Calories: 37 .........................................................................................................(2%)
• Carbohydrates: 8.5 g ...........................................................................................(3%)
• Fibre: 5 g .............................................................................................................(19%)
• Fat: 0.1 g .............................................................................................................
• Sugar: 3.5 g ........................................................................................................
• Protein: 2.3 g .......................................................................................................(5%)
• Vitamin C: 84 mg .................................................................................................(140%)
• A lot of Water

Phototrophism

         

          Phototropism is the growth of a specific part of a plant towards, or in the direction of a light source. The whole organism does not move, it is just the certain part and this happens mainly in plants, but it can happen in other types of organism too. Positive Phototropism is when the part grows toward the light source, where as negative phototropism is when the part grows away from the light source.

 

 

Cotyledon and it's significance

          A cotyledon is a leaf of the embryo of a seed-bearing plant. Once a seed has germinated, the cotyledons become green. Cotyledons are significant because they store nutrients for the embryo. They are also important because they are the first part of the plant which breaks through the surface or ground of what it is growing in. Once it is exposed to light, it goes through the process of photosynthesis and starts to make glucose. This is very important to the plant, because this is how the plant gets its food and energy. There are two types of cotyledon plants. The dicotyledon has two cotyledons, and they are normally net veined The monocotyledon, which only has one cotyledon, has leaf veins that are parallel to each other.

The Kohlrabi has two cotyledons, so it is a dictoyledon.

Growth Parameters

• Size: 20-25 cm
• Light: Full Sun
• Soil: Well drained organic soil
• Temperature: Below 40 degrees/ cool temperatures
• Time: 40-75 days (depends on conditions)
• Humidity: Average (better with low humidity)

Sprouting Method

          Sprouting can be done in many ways using jars, cloths, trays, sprouting bags and many more. The method we have chosen to explain involves using cloths.
 

1.      Place Kohlrabi seeds on a tray lined with a wet cloth.

2.      Place a second wet cloth on top of the seeds to keep them moist. If necessary, sprinkle water on top of the cloth every 12 hours to keep the seeds hydrated as time passes.
         The process of soaking the seeds will speed up the germination rate and reduce growing time, once the Kohlrabi seeds are planted in the ground, by days or even weeks.

Seed Anatomy
 

 

Hypothesis

        The objective of the Kohlrabi Germination Experiment is to test and determine which of the following three temperatures is best for Kohlrabi seed growth: Room temperature, Heat Mat temperature and Refrigerator temperature. As a group, we believe that the Kohlrabi seeds that will show the fastest germination rate will be the Heat Mat seeds, with a temperature of 32 degrees Celsius.

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.