Activity
The purpose of this lesson
is to discover misconceptions or naïve ideas held
by the students in the area of biological tactics in IPM.
Once the teacher is aware of the students’ various
current knowledge and ideas, the subsequent lessons can
be tailored to allow students an opportunity to adopt scientifically
sound conceptions. The discussion should also increase
the students’ interest in learning about IPM beneficials.
1. Engages the students in a discussion regarding biological forms of pest
control. To start the discussion, ask students for examples from their experience,
or from previous lessons. (Ex. Ladybird beetles and aphids, Bt and gypsy moths,
Praying mantids)
Guide the discussion toward details of using beneficial insects. In groups,
students list their ideas, and their questions. Keep this group list for later
assessment purposes: what have you learned? List examples of students’ ideas
on a board or overhead in three categories: What they know, what they think
they know, and what they need to know more about in order to use this strategy.
Narrow the discussion to focus on ladybugs and aphids. What do the students
know, what do they want to know and how can they find out?
2.
Separate the list of questions into Library research
and Laboratory research. Save library research
questions for lesson 3.
(Day
1 and 2)
3. Students make observations of aphids and ladybird
beetles. They recognize questions that are
testable with the given materials.
i. Provide each group of students with 3 plastic
Petri dishes: one with a few aphids, one with
2 or 3 ladybird beetles, and one empty.
ii. Allow 10-15 minutes for observation of
the insects – first each insect alone and then
together. What are they doing?
iii. Each group lists 5 questions regarding
the insects.
4. Share some of the questions as a class.
Look at the lists and decide which are scientific
and questionable. Possible questions that
might arise are: How many aphids can a ladybird
beetle
eat before it is satiated? How long does
it take
a ladybird beetle to eat an aphid? Do ladybird
beetles prefer smaller or larger aphids?
How do ladybird beetles find the aphids? Does
temperature
have an effect on feeding behavior? Is ladybird
beetle behavior affected by light or dark?
5. Students choose a question and design
an experiment to test this question.
6. Students conduct experiment.
7. Students generate a claim that summarizes
their results and explains/justifies to
the class how they arrived at their claim
from
their data.
8. Divide students into “expert” groups
of 3 to 5. Depending on the number of groups
in your class, divide the articles into
that many sections. At the discretion of
the teacher,
some paragraphs may be eliminated. Each
expert group reads the article or section
of an article
assigned to it, and outlines the important
concepts.
9. Reassemble the groups in a jigsaw procedure
such that the new groups have one member
of each expert group. Ask students to retrieve
their
library investigation question list. Pass
our
additional question sheets. Groups use
their combined knowledge to answer questions.
All
group members are responsible for learning
all the
important concepts, with the help and coaching
of the other group members.
Important concepts about ladybird beetles
and aphids.
Sample questions are:
Is there a difference between a ladybird
beetle and a ladybug?
List, in order, the general classification
of the lady beetle, from Kingdom to Order.
What characteristics are used to place
the ladybird beetle in its classification
order?
Why is the ladybird beetle so important
to farmers and gardeners?
How is the use of
ladybird beetles a form of IPM?
Are ladybird beetles most commonly used as
biocontrol agents to native or non-native species?
What pest is controlled and what crop benefits?
What are two ways that non-native species immigrate to the U.S.?
List at least three other biocontrol agents. What pest is controlled? What crop
benefits?
Which ladybird beetle is commonly seen congregating on buildings and windows
in the fall?
Briefly lay out the lifecycle of the ladybird beetle.
What is the favorite food of ladybird beetles?
Why do you think that scientists have found it necessary to import biocontrol
species?
To what insect order does the aphid belong? What characteristics are used for
classification? What is the lifecycle of an aphid? Explain how parthenogenesis
is demonstrated by aphids. What is an aphid’s preferred food? (What part
of the plant?)
Does an aphid have any defense mechanisms?
PA
IPM website: http://paipm.cas.psu.edu/tactics.html
10. In groups, the students will outline a plan that
follows IPM tactics to control an aphid problem in
a greenhouse.
Specific information about this greenhouse:
a. There are an estimated 50aphids per plant
b. There are currently 5000 infested plants in the greenhouse.
c. The threshold has been exceeded.
11. Using what you have learned, what specific steps will you take to reduce
the aphid problem?
12. Present students with the following individual homework assignment.
i. Ask students to choose an insect that presents a personal problem for them.
ii. Use their library research skills to learn more about their insect.
a. What is the lifecycle of your insect?
b. What is the habitat of your insect?
c. Does your insect have any natural enemies?
d. Population estimates?
13. Following the strategies suggested in the PA IPM website, draft a plan
to manage your insect.
a. Can you use any of the above information to develop a control plan for your
pest?
b. What additional information do you need?
Stress that students should look for the most effective strategy that rids
them of the pest, but has the least environmental health risks. Evaluate students
on the thoroughness of their plan. Students can also be evaluated on the completion
of the investigation report and information report. |
Embedded
Assessment |
