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The Plant Mass of Tomatoes Grown in Different Environments

Researched by Whitney K.
2003-04

PURPOSE

In the first phase of the experiment, the purpose was to measure the mass of tomato plants grown in different temperatures. In the second phase of this experiment the purpose was to measure the mass of the tomato plants grown in different soil moisture levels.  

I became interested in this idea when my grandma complained about how her plants had trouble growing in our environment since it is so hot and dry.

The information gained from this experiment would help farmers and/or gardeners know the best environment for growing tomatoes, and how much water to add to them.

HYPOTHESIS

My hypothesis for the first phase was that the tomatoes would have greatest plant mass in the environment with high temperatures. My hypothesis for the second phase was that the tomatoes would have greatest plant mass in the environment with high soil moisture.  

I based my hypothesis on a book called Tropical Rain Forests by April Sayer ?Pulley. She indicates, “Rain forests get a lot of rain. ” She added, “The humidity is extremely high, because of the heat from the sun. ”  Since plants need a lot of water, but not too much, the fact that it rains a lot is good. Since it is hot if it rains too much than the heat will make some of the extra water evaporate.

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EXPERIMENT DESIGN

The constants in this study were:
* Growing temperature for all of one group
* Seed age
* Type of seed (steak tomatoes)
* Brand of seed
* Size of pot
* Potting depth
* Shape of pot
* Amount of soil
* Type of soil
* Lighting 
* Type of grow light
* Type of plant
* Scale used to weigh tomatoes
* Time tomato plants are picked at conclusion of experiment
* Length of time tomato plants are allowed to grow
* Size of the tent
* Material made for tent (PVC pipes, black plastic, clear tape)
* Time of day plants are watered

Variables:

The first manipulated variable was the temperature of the three “tents”. The second manipulated variable was the amount of water added to the two test groups in each of the three “tents”.  

The responding variable was the mass of the tomato plants after they have grown for four weeks.

To measure the responding variable the tomato plants are pulled, roots and all, and weighed on a triple beam balance.

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MATERIALS


QUANTITY
ITEM DESCRIPTION
8
 Packs of tomato seeds
3
“Tents” (PVC pipes, black plastic, clear tape)
3 
Bags of soil
3 
Heat lamps 
12
Pots
1
Triple beam balance
1
Measuring cup

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PROCEDURES

1. Germinate seeds for two weeks to allow plants to start.
2. Design an accurate drawing of the tent fame and build three “tents”: 
A) Cut PVC according to design and put together.  
B) Tape black plastic around PVC pipes so that the heat is held in and it makes a tent like structure.
C) Put a thermometer inside each of the tents so that the temperature can be monitored.
D) Put grow light in each tent.
3. Put “tent 1” in my garage (coldest environment).
4. Put “tent 2” in my living room, nearest to the home heating vent (warmest environment).
5. Put “tent 3” in my living room (away from home heating vent). Cut slits in the top of the “tent” to allow heat to rise out of the “tent” (close to room temperature).
6. Get twelve little pots (four per tent) and put them on the plastic covered floor.
7. Open up the bag of soil.
8. Put soil in each pot 8 cm above rim.
9. Germinated starts are placed into pots.
10. Put four planted pots in each tent directly under grow light.
11. Label two pots “A” and two pots “B” in each tent. Pots “A” receive 360 ml water and Pots “B” receive 120 ml water.
12. Water pots “A” and “B” in each of the tents every four days at 5:30pm.
13. Make sure that the tent in my garage is approximately 10 C*.
14. Make sure that the tent in my living room next to the heater is approximately 27 C*.
15. Make sure that the tent in my room is approximately 24 C*.
16. Document temperature and amount of water of pots in each tent every time they are watered.
17. At conclusion of experiment, weigh the plant mass with a triple beam balance.
A) Pick all of the tomato plants from the “tent 1” and weigh them.
B) Repeat above for “tent 2” and “tent3. ”
18. Record data in science notebook.

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RESULTS

The original purpose of the first phase of the experiment was to measure the plant mass of the tomato plant grown in different temperatures. In the second phase the purpose was to measure the plant mass of the tomato plants grown in different soil moisture levels.  

The results of the experiment were that the tomato plants in the 25°C that were given 120 ml of water weighed the most.  

See My Data Table and Graph.

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CONCLUSION

My hypothesis for the first phase was that the tomatoes would have greatest plant mass in the environment with high temperatures.  

The results indicate that this hypothesis should be accepted.  

My hypothesis for the second phase was that the tomatoes would have greatest plant mass in the environment with high soil moisture.  

The results indicate that this hypothesis should be accepted

Because of the results of this experiment, I wonder if tomato plants would grow better in even warmer temperatures.  

If I were to conduct this project again I would have started growing my tomato plans earlier so that they would have more time to grow and I would have but more plants per group.  

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RESEARCH REPORT

Introduction

 Agriculture provides the world with food through the growth of plants and animals. Over thousands of years, scientists have studied these laws and have found out how and why plants and vegetables grow. The tomato plant is just one of the many plants that have been studied over the years. Like almost all plants in the world, the tomato plant uses the process of germination and photosynthesis to grow and produce fruit.  

Agriculture

 In addition to being one of the most popular industries, agriculture provides us with food, shelter and clothes. It was developed 11,000 years ago, making it one of the oldest industries. Before people developed agriculture they had few other activities besides finding food, clothes, and wild plants for themselves. The farmers were more successful than the hunters. Almost all of the world’s foods come from farmers and their crops. There are six groups of well-known food crops: dry beans (pulses), vegetables and fruit, oily crops like coconuts, sugary crops like sugar cane, nuts, tea and coffee beans.  

Germination

 Germination is the process of sprouting seeds. To germinate seeds you need moisture soil, plenty of oxygen, and warmth (but not too much). Most seeds that go through a dormant stage can stop germinating for weeks. Dormancy is a process that almost every seed goes through. When a plant goes through dormancy it has to break its other skin layer before it starts to germinate again. Dehydration is very common when plants go through its stage of dormancy. Suring re hydration the plants might start to swell from sucking up a lot of water. The plant splits open after the swelling and creates a root deep in the ground. After the root has grown, the plant starts to grow leaves. The root can then get its food from the leaf that is full of water and minerals

Cotyledon

 Cotyledon is a part inside of the seed that comes as a seed sprouts young leaves. Angiosperms (plants that flower) have two or less cotyledons. A plant with only one is referred to as a monocot or monocotyledon. Plants with two of them are referred to as dicots or dicotyeldons.  

Photosynthesis

 Out of all the parts of the plant, the leaf is the most important part. It provides and produces the food that the plant produces. It also carries many minerals and water. On the bottom of the leaf there are small stomata (pores) that allow air to enter the lungs of the plant. The outside of the plant has a layer of wax to help the plant stay moist.  

Chlorophyll

 Chlorophyll is the material that gives the leaf its green color. The energy from the sun and chlorophyll helps leaves to create food (photosynthesis). To supply the photosynthesis process, a plant needs water and carbon dioxide. To get air, the plant uses the stomata to let the carbon dioxide in. To get water, the plant uses roots to gather up the water.  

Tomato

 It takes 40-75 days for tomatoes to grow. Tomatoes start out as small yellow seeds before the germination starts. They need well-drained, warm fertile soil, and at least 6 hours of sunlight. They can produce 10 to 15 pounds of tomatoes per plant. The different kinds of tomatoes are: sunfay, big boy, ponderosa (that weigh over three pounds), and micron-ton (a kind that produces excellent tomatoes and can be grown indoors and outdoors). To keep your tomato plants from going all over the place you can put stakes in the ground next to them. Putting in stakes can also help your tomato plant from getting “fruit rot”. Some of the most common fruit diseases are: “bacterial wilt,” “fusarium wilt,” and “veticullium wilt. ”
 The tomatoes belong to the same family of plants as the Belladonna (deadly nightshade).  

Belladonna (deadly nightshade)

 Belladonna is a deadly plant mostly found in Europe and Asia. It is 20 cm in length and grows deadly black berries on its green leaves. People sometimes use the Belladonna leaves to make drugs.  

Summary

 Since agriculture first began many thousands of years ago, we have learned a lot about plants and how they grow. We have discovered that through the process of germination, by placing seeds in moist soil in warm temperatures, seeds can sprout roots and grow. Photosynthesis produces all food on earth.

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BIBLIOGRAPHY

Arnold, James “Crop”, World Book Encyclopedia, 1999.

“Desert”, ENCARTA Encyclopedia Deluxe, 2000.

George, William L. Jr. “Tomato” World Book Encyclopedia, 1998.

“Germination”, World Book Encyclopedia, 1999.

“Cotyledon”, World Book Encyclopedia, 1999.

“Heat lamps”. Efunda. December 3, 2003
 http://efunda. globalspec. com/LearnMore/Optics_Optical_components/Light_Sources

Hershey, David. Plant Biology selah schools, science project, SIS science, S.I.S.. New York, New York: John Wiley and Sons, 1-13.  

“Plant”, World Book Encyclopedia, 1999.

“Rain Forest”, ENCARTA Encyclopedia Deluxe, 2000.

Sayre-Pulley, April. Wetlands. Brookfield, Connecticut: Twenty first Century Books, 1996. 9-10.  

“Tomato”, ENCARTA Encyclopedia Deluxe, 2000.

 “Wetlands”, ENCARTA Encyclopedia Deluxe, 2000.

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ACKNOWLEDGEMENTS

I would like to thank the following people for helping make my project possible:
* My dad and for buying all of my materials and helping me set up my “tents”.  
* My mom for taking pictures of me while I worked.  
* Mr. Newkirk for correcting all of my rough drafts and showing me how to create a nice board.  
* Mrs. Helms for helping me make my borders on my board straight.  

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