What Household Detergent 
Repel Aphids Best?

Researched by John H.
2000-01
PURPOSE

The purpose of this experiment was to determine if household detergents repelled aphids. 

I became interested in this idea when aphids ate holes in my apples, but I did not want to get special pesticides for the job.

The information gained from this experiment will help people to know whether household detergents will work as an organic pesticide against aphids.

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HYPOTHESIS

My hypothesis was that the dish detergent would work the best to repel aphids.

I base my hypothesis on the fact that I have seen the effects of household detergents in gardens.  My mom uses a mixture of dish detergent and water on her roses and gourds to keep away flies.

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EXPERIMENT DESIGN

The constants in this study were:

  •  Type of aphids
  •  Feeding method
  •  Container the flies are kept in
  •  Container the experiment is done in
  •  Environment that the flies and the repellents are stored in
  •  Amount of detergents


    • The manipulated variable was type of repellent used.

    The responding variable was number of aphids in the half of the container with the apple and the half without the apple.

    To measure the responding variable I counted the number of aphids on each side.

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    MATERIALS
    QUANTITY 
    ITEM DESCRIPTION
       240
       Aphids
      3 oz.
       Dish Detergent
       3 oz.
       Shampoo
       3 oz.
       Vinegar
       24 oz.
       Water
       12
       Medium Zip-Lock Bags
       2
       Apples
       4
       Spray Bottles
       1 Roll
       Masking Tape

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     PROCEDURES
    1.  Get all materials.
    2.  Take 20 fruit flies and put them in one of the bags.
    3.  Tape a line dividing the bag in to two halves.
    4.  Mix a solution of 1 oz. of shampoo and one cup of water and put it in the spray bottle.
    5.  Wash an apple without soap.  Cut it into 8ths, then spray 8 with the shampoo solution.
    6.  Place the sprayed apple slices in the bags, holding the fruit flies.
    7.  After the aphids have been in the bag with the apple for 15 minutes, count how many are on the side of the bag with the apple. 
    8. Record results
    9.  Count again at 30 min. and record.
    10.  Count again at 1 hr. and record.
    11.  Repeat steps 3-9 two more times with the remaining apple slices.
    12.  Repeat steps 3-9 using a 1 oz.  dish detergent with 1 cup water, 1 oz. Vinegar with 1 cup water.  Cut up more apples as needed.
    13.  With each mixture do 3 trials in a different bag and use a different apple slices in each experiment.
    14.  Record all results.
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    RESULTS

    The original purpose was to determine if household detergents repelled aphids.
    The results of the experiment were that vinegar worked the best for repelling aphids.
    See the table and graphs.

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     CONCLUSION

    My hypothesis was that dish detergent would work the best at repelling aphids.
    The results indicate that this hypothesis should be rejected because vinegar worked the best.
    I think that the shampoo and dish detergent was  to weak of solution.
    Because of the results of this experiment, I wonder if different strengths would work for longer periods of time.

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    RESEARCH REPORT

    Introduction

    Pesticides are very harmful to the environment.  Natural pesticides have been discovered, but are expensive.  Household detergents have been used in place of natural pesticides against aphids.

    Pesticides

    Pesticides have very harmful effects on some plants, animals, and most importantly people.  After being sprayed onto crops, they get into the ground water.  From the earth they get into streams and the rivers.  Animals drink the contaminated water and get sick or die.  Birds also eat the seeds that the weeds and other plants make, but those plants are contaminated.  Pesticides harm people when plants are eaten with pesticides still on them.  Another hazard is the field workers can get sprayed with pesticides, which causes rashes, burns, and diseases.

    Natural Pesticides

    Natural pesticides are made from plants.  Most often they are used to repel instead of kill,  like pesticides.  Pyrethrum and Neem Tree Oil are two examples that are made from plants.

    Household Detergents

    Some household detergents are considered a pesticide, Clorox and ammonia are too.  However, shampoo, dish detergent, vinegar, and hand soap are not considered as pesticides.  When used as a repellent, household detergents are usually diluted in water.  The aphids apparently do not like the smell of the detergents.  Again they do not kill, but only repel.

    Aphids

    An aphid is a small insect that feeds on fruit and vegetables.  It is considered  a pest to farmers and gardeners.  It is also called a green fly or fruit fly.  Their enemies are birds, spiders, parasitic wasps (also used as biologic pest control), hover-fly larvae, and ladybugs.  Aphids are classified in the family of aphidiae and in the order of homoptera.  The presence of aphids can be detected by marks, wrinkles, and abnormalities on the leaves of plants.  Aphids reproduce by the females digging holes about 3 cm. down.  The eggs hatch into larvae and then they feed on decaying apples and other rotting fruit, Then, after a week, they emerge as aphids.

    Summary

    Pesticides should be used less because of their harmful effects.  Natural pesticides should be used, but if they became too expensive household detergents could be used.

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    BIBLIOGRAPHY


     "Aphid" Encarta, 2000.

     "Aphid," "World Book Encyclopedia"

     Coble, Harold D. "Insecticide" The World Book Encyclopedia, 1999  Vol. 16 pg. 302-303

     "Fruit Fly" Encarta. 2000

     Dave, Kopel "Common Sense About Pesticides," [Online available at] http://www.i2i.org/SuptDocs/enpesic.htm 

     "Jerry Baker,"  [Online available at] http://www.jerrybaker.com

     "What  is a  Pesticide" [Online available at] http://enviroment.about.com/newsissues/enviroment Downloaded 11/7/00

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    ACKNOWLEDGEMENTS

    I would like to thank my mom for keeping me motivaed and helping with my presentaion.  I would also want to thank my dad for helping me with my experiment.  And last but not least, 
    Mr. N and Mrs. P, my teachers.

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