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PURPOSE
The purpose of this experiment was to determine the effect
of organic pesticides on ladybugs.
I became interested in this idea because I knew ladybugs
were helpful insects and I wanted to find a way to keep them alive when
farmers spray their crops.
The information gained from this experiment will help
farmers pick organic pesticides that will not harm helpful insects such
as ladybugs.
HYPOTHESIS
My hypothesis is that the jalapeño pepper spray
will kill the most ladybugs compared to garlic, pyrethrum, and dill leaves.
I base my hypothesis on http://www.toaherbfarm.com/herbs/resources/bugspray.htm,
which states " Peppers and other hot dusts will kill ladybeetles but do
not appear harmful to beneficial insects . "
EXPERIMENT DESIGN
The constants in this study were:
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Same temperature of room where experiment was conducted
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Same amount of ladybugs per container (25)
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Same number of trials for each type of pesticide (3)
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Same size of container which hold ladybugs
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Same amount of pesticide in each spray bottle.(15 grams)
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Same amount of water in each spray (100 milliliters)
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Same size spray bottle
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Same amount of potato in each container (100 grams
per container)
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Same amount of pesticide for each trial
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Same amount of time for each trial
-
Same temperature of water to make pesticide infusion
(boiling)
The manipulated variable was the different kind of organic
pesticides that were used during the time of this experiment.
The responding variable was the amount of ladybugs that
survived during the experiment.
To measure the responding variable I will count the amount
of ladybugs that died, then subtract that from 25.
MATERIALS
| QUANTITY |
ITEM DESCRIPTION |
| 45 grams |
Dried dill weed leaves |
| 45 grams |
Garlic |
| 45 grams |
Pyrethrum Powder |
| 45 grams |
Jalapeño Peppers |
| 15 |
clear plastic cups |
| 600 milliliters |
boiling water |
| 700 grams |
potatoe peelings |
| 1 |
marker or pen |
| 15 |
10x10 cm pieces of tin foil |
| 1 |
spoon |
| 15 |
rubberbands |
PROCEDURES
Preparation
1. Slice 15 grams of garlic into square about 5 square
millimeters.
2. Put cubed garlic into 100 milliliters of boiling water
and let it soak for 13 hours.
3. Mix 15 grams of pyrethrum powder with 100 milliliters
and let soak for 13 hours.
4. Mince 15 grams of dried dill leaves
5. Put minced dill leaves in 100 milliliters of boiling
water and let soak for 13 hours.
6. While your pesticides are soaking label three clear
plastic cups "Jalapeño Peppers"
7. Repeat step 6 with "Garlic," "Pyrethrum," "Dill Weed,"
and "Control Group."
8. Label a spray bottle "Peppers"
9. Repeat step 11 with "Garlic," "Pyrethrum," "Dill Weed,"
and "Control Group."
10. Pour the newly made jalapeño pepper
spray into the spray bottle labeled "Peppers"
11. Repeat step 13 accordingly to their labels.
12. Slice several potatoes into 100 gram pieces.
13. Put a 100 gram piece of potato into each disposable
container.
14. Place 25 ladybugs into each clear plastic cup.
15. Put a piece of tin foil over the cup so the ladybugs
cannot escape.
16. Spray each container of ladybugs three times with
the spray determined by the label on the container.
17. 3 hours later record data and spray ladybugs.
18. Repeat step 16 six more times
19. 3 hours later record.
20. Enter the results in the data table.
21. Draw Conclusions.
22. Dispose of all sprays, dead ladybugs, containers
and all other materials, which cannot be reused.
23. Let the live ladybugs to go free when the weather
is appropriate.
RESULTS
The original purpose of this experiment was to determine
the effect of organic pesticides on ladybugs.
The average amount of surviving ladybugs sprayed with
dill weed spray was 9. The average amount of surviving ladybugs sprayed
with pyrethrum spray was 0. The average amount of surviving ladybugs sprayed
with Jalapeño Pepper spray was 10.3. The average amount of surviving
ladybugs sprayed with garlic was 5.3. The average amount of ladybugs surviving
in the control group was 25.
View my data and graphs.
CONCLUSION
My hypothesis was that the jalapeño pepper spray
would kill the most ladybugs compared to garlic, pyrethrum, and dill leaves.
The results indicate that this hypothesis should be rejected.
Because of the results of this experiment, I wonder if
I were to do more trials for a longer period of time the results would
be different.
If I were to conduct this experiment again I would use
a larger sample size with more ladybugs in each trial and more trials.
I would also use a larger variety of pesticides. I would have had
longer trial times, at least until all of the ladybugs were dead.
I would spray the ladybugs more often or spray them with more solution
when I did. I would have added a second control group, in which I sprayed
the ladybugs with pure water, to see if simply being sprayed affected them.
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RESEARCH REPORT
LADYBUGS
INTRODUCTION
Ladybugs are very beneficial beetles. They can be used
for types of pest control because they eat mainly scale insects. Pest control
is anything that reduces the life span of insects or any other small creatures.
NAME
The ladybug is scientifically classified as Coleoptera.
It is a type of beetle, which is the largest group of insects, and has
30,000 species, but only 150 beetle species live in the United States.
Two other names are Asian Ladybeetle and the Vedilia Beetle. They have
had their name since the Middle Ages, and they have been listed as one
of the most beneficial insects in the United States. Some people consider
ladybugs a gift from the Virgin Mary because of their love for aphids.
CHARACTERISTICS
All species of ladybugs have a different sense of smell.
They use their antennae to smell. They all have six legs. Basically ladybugs
all are red, orange, or yellow. Commonly they’re 1/4 inch long, and are
generally oval shaped.
All coleoptera have a pair of hard shiny wings called
elytra. The elytra cover a soft pair of wings, which they use to fly. When
a ladybug flies they use their under pair of wings and move the elytra
out to the side.
A way to tell different ladybug species is by
their color and marking. However some species look different. These variations
are most likely caused by the habitat and conditions they are used to living
in.
DIET
The ladybug is a carnivore, and isn’t a picky eater because
they will eat almost any type of scale insect.
Aphids are known to be their favorite food. Aphids
will eat almost all plants. They suck the liquids out of the leaves. This
leaves a shiny substance called "honeydew" which attracts ants and sooty
mold. This makes plants wilt and die earlier than naturally. It can take
up to five minutes for a ladybug to devour a whole aphid, which are usually
1/16 to 1/8" inches long. Even the larvae eat aphids, though they just
pierce the skin and suck out the liquids. A small ladybug can eat to up
three hundred aphids by the time it becomes an adult. They would even eat
their own eggs if they had nothing left to eat. The ladybugs get the nutrients
of the plants through the aphids that they eat.
MYTHS
To some people ladybugs have been considered a symbol
of good luck. Some cultures even believe they are "sent from heaven" to
save their crops. It is also believed that ladybugs are a sign of a plentiful
harvest and good weather.
HISTORY
In the 1980’s about 88,000 ladybugs were imported from
Asia to save the citrus crops of California from the cottony-cushion, a
scale insect. Since then hundreds of species have been sent to the United
States.
MATING
Adult ladybugs need a place where there is nectar and
pollen to lay their eggs. Males find females just by instinct. They can
only mate with ladybugs of the same species. Usually they mate on a leaf
with lots of aphids. The eggs, which are bright yellow and about 1.5 millimeters
long, turn white after a few days, and hatch about one week after being
laid on the stem of a leaf.
HABITAT
Commonly ladybugs are found in places that have tropical
to moderate temperature. They are tree-dwelling insects so they live near
places with trees. They cannot live indoors because in those conditions
they wouldn’t be able to reproduce. Some larval ladybugs can even live
under water.
DEFENSES
Ladybugs have special defense against predators.
The larval ladybugs can produce a yellow and sticky substance, which smells
very bad, from their knees. The adults can produce this same substance
from the abdomen. This is called "reflex bleeding." If the blood gets in
the predator’s mouth it will lose interests and spit it back out. That
teaches them not to make meals of ladybugs in the future.
HIBERNATION
Ladybugs are cold-blooded so they hibernate in the
winter. They will get into buildings through bad foundations, poor insulation,
cracks or windows.
Since ladybugs are tree dwelling insects so buildings
in heavily wooded areas are most likely to get infested. They are also
attracted to brighter colored houses.
Ladybugs can be winter pests, because if squished can
leave yellow-orange stain. Usually will be asleep, but if disturbed might
bite. Fortunately though they don’t carry diseases.
When inside their winter destination they hibernate until
it is warm again. But on warm days they will come out for a little while
to enjoy the warmth of the sun. They come out of hibernation when the spring
flowers bloom or when it is 15°C. (59°F)
PROS AND CONS OF LADYBUGS
Ladybugs are very beneficial because of their appetite for
aphids. They can be used as biological pest control. Every species but
two are beneficial for farmers. Farmers can collect them when hibernating
and be used later on for biological pest control.
However they can be pests if they gather in large
numbers to hibernate, and you don’t appreciate their presence. There are
a few harmful types of ladybugs can destroy crops.
LIFE CYCLE
Some ladybugs can live up to two to three years. The
ladybug has four main stages of life. The first is the egg; the second
is the larval stage; the third is the pupal stage; the last stage is the
adult.
During the lifetime the body size increases while
the exoskeleton doesn’t. So it gets molted, which is like shedding the
outer shell. This happens about four times in its lifetime. The fourth
time this happens it is called a pupa, and goes through a stage called
metamorphosis, the time when its final colors and spots begin to show.
Metamorphosis lasts about one week, during this time the beetle does not
move unless it is disturbed or to regulate the body temperature. After
metamorphosis the pupa has undeveloped adult body parts.
PEST CONTROL
HOMEMADE SPRAYS
A few types of homemade organic sprays include herbal sprays,
alcohol sprays, garlic sprays, and hot dust sprays. The aroma is used to
repel insects.
Ways to make them are to mix dried or fresh leaves
with boiling water. As an example wormwood and nasturtium repel aphids,
as does the extract of marigolds. Also the alcohol extracts of hyssop,
thyme, and white clover repel insects.
Several types of alcohol can be used as a spray
against harmful insects. It works especially well on aphids and other scale
insects. It doesn't work well on most beneficial insects such as adult
ladybeetles.
Hot dusts work well for a fast kill, on aphids and other
insects. Some "hot dusts" are chili peppers black peppers, dill, ginger,
paprika, and red peppers. They contain capsaicin, which repels insects.
In one case it was recorded that 1/25 of an ounce reduced the number of
onion maggot eggs by 75%
Garlic also has a quick kill against aphids and
many other scale insects. It is also known to be used as an effective fungicide
as well as an insecticide. When mixed with mineral oil and soap it is toxic.
ORGANIC
Organic doesn’t always mean chemical free. In fact
about 50% of all organic pesticides contain carcinogenic compounds, which
are a risk factor of cancer
Some advantages of organic pesticides over synthetic
pesticides are that they are usually more environmentally friendly. Some
plants can be used as organic pest control and at the same strength can
be uses as herbal remedies or made into teas.
Some disadvantages are that sometimes you would have
to use two to three times more of an organic pesticide that you would use
to get the same effect as a synthetic one, and that would cost more for
farmers.
SYNTHETIC
Synthetic pesticides are usually made out of chemicals, which
don’t have a very good effect on nature.
Some advantages of synthetic pesticide use are
that you usually don’t have to use as much as when using an organic pesticide.
That would save the grower money. Most of the time it has a quicker kill
of insects.
The disadvantages of using synthetic pesticides
are that they have a bad effect on the environment. Toxins in some can
kill fish and birds.
An example is DDT, which stands for dichloro-dypenyl-trichloroethane.
Plants and animal can absorb it, and there have also been traces of it
in humans. This is because they ate something with DDT in its system. The
difference between DDT and other pesticide is that it lasts a lot longer.
When too much is applied it hurts both beneficial and harmful insects and
if a fish or birds gets too much exposure to it, it could kill them. DDT
affects the nervous system. In the past it was used commonly when mixed
with other chemicals. Fortunately it was banned in 1972, because it contaminated
food so all uses were banned. However it is still used in parts of the
world.
PEST CONTROL
Pest control is anything that reduces the life span of insects
or other creatures. There are three main types: chemical, physical, and
biological mechanisms.
Chemical is when you use any type of pesticide. Like
when spraying crops with an insecticide.
Physical is like when the crops are changed each
year. As an example, one year you would plant corn, and the next year you
would plant tomatoes. When you do this you would pick a crop that the insect
you had a problem with that year didn’t like. Then it would move somewhere
else.
Biological does not involve chemicals. As an example
farmers use one insect to treat a different one. As an example in the 1990’s
ladybugs were imported to California to kill the cottony-cushion, a small
scale insect.
EFFECTS OF PESTICIDES
In some cases pests can become immune to the pesticide.
Then a higher dosage might be needed. In one case 600 different plants
and animals were immune to the same chemical.
CONCLUSION
In conclusion the ladybeetle is a very helpful creature in
many ways. Pest control is also good for relieving people of the annoyance
of pests, but isn’t always healthy for the environment. |
BIBLIOGRAPHY
"Aphids." <http://www.forestry.mpw.net/html/aphids.html>
October 29th, 2001
Arnett, R. H. Jr., "Ladybug." Americana Encyclopedia 1999,
Volume 16, Page 657
"Asian Lady Beetle Facts." <http://www.ladybuglady.com/asianladybeetle.htm>
November 3rd, 2002
"Bug Sprays." November 3rd, 2002 <http://www.toaherbfarm.com/herbs/resources/bugspray.htm>
Coble, Harold D., "DDT." World Book Encyclopedia
1999, Volume 4, Page 55.
Doris, Ellen Entomology, New York, Henry Holt and Company.
1994 Page 50.
"Ladybug", Encarta Encyclopedia 2001
Facklam, Howard and Margery, Insects, NY, Henry and Holt
Co. 1995, Pp. 50-51
Gadwood, Robert C., "Organic Chemistry", World Book Encyclopedia
1999, P 853
"Garlic Spray May Keep Pests Away." <http://www.agnew.tamu.edu/stories/ento/oct2897a.html>
November 12th, 2001
"Herbs to Attract and Repel Insects", November 11th, 2001
<http://www.toaherbfarm.com/herb/resources/herbbugcompanion.com>
Johnson, Sylvia A., Ladybug, Minniapolis, Lerner Publications
Company, 1983
Kionka, Michael J., "Neem Tree Oil", World Book Encyclopedia
1999, Page 114
"Ladybug." <http://www.bugtech.com/bug/id/asianlb01.htmlhabits/control&prevention>
Nov. 3rd, 2001
"Ladybugs." <http://www.ladybuglady.com/article/htm>
November 13th, 2001
"Ladybugs." <http://www.doyourownpestcontrol.com/ladybugs.htm>"
Oct. 19th, 2001
Linker, Michael H., "Pest Control." World Book Encyclopedia
1999, Pp. 317-318
Martinson, Candice, "Ladybug." World Book Encyclopedia
1999, Pp. 25-26
"Organic Pesticides." November 3rd, 2001 <http://www.ibiblio.org/london/agriculture/general/1/msg000.19.html>
"Pest Control." Encarta Encyclopedia Deluxe 2001.
"Pyrethrum." <http://www.nf-2000.org/secure/crops/s616.htm>
November 21st, 2001
Van Dyke, Sara, Insect Wars, Danbury, CT, Grolier Publishing,
1997, Pp. 10-14
"Why Organic?" <http://www.pepperjoe.com/about/> November
14th, 2001
Young, Jerry and Kindersley, Dorling "Ladybird Beetle."
Encarta Deluxe 2001.
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ACKNOWLEDGEMENTS
I would like to thank the following people for helping me
with work on my science project:
~Mr. Newkirk for helping me with editing things in my
journal and report.
~Mrs. Helms for giving me help with finding places to
buy the ladybugs, and giving me advice on where to put things on my projet
board.
~Hali, for helping me decide what colors of boarders
I used on my project display board.
~my dad, for helping me put the ladybugs in the cups
when i started my experiment.
~my mom for buying the supplies that i needed for my
experiment.
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