Title: Principles of IPM: Methods of Control
Learning Objective: To understand the various methods of pest control utilized in an IPM program.
Materials: Presentation board (chalk board or flip chart) or slide projector, chalk or pen and lesson hand out.
Time Needed: 3 hours
Power Point Presentation: Lesson 5 (computer file: lesson5.ppt)
Opening: In the beginning of our discussion of Integrated Pest Management, we defined it as "the use of many pest control methods in a well organized and harmonious way in order to achieve long-term pest control". We have learned everything about this definition except it’s essential ingredient, the use of many pest control methods. In this section we will learn about the variety of pest control methods in the quiver of the IPM practitioner as they control pests.
Procedure:
Methods of Control
A. Criteria for selecting a treatment strategy
A treatment strategy should be selected which is:
- most likely to produce an economic reduction of the pest population.
- least disruptive of natural controls.
- least hazardous to human health.
- least toxic to non-target organisms
- least damaging to the general environment.
- easiest to carry out effectively.
- most cost effective over both the short and long terms.
B. Methods of control
1. Cultural Controls
a. Definition: Manipulation of cultural practices to the disadvantage of the
pest.
b. Methods
i. Soils and Nutrition: plants with adequate nutrition can grow more
vigorously, allowing them to better tolerate pest damage or to compete
better with weeds. Soil cultivation can also kill some pests
ii. Water Management:
- Too Little Water: poor plant growth, less vigorous plants, and
more susceptible to pest injury
- Too Much Water: can contribute to development of many
diseases
iii. Sanitation:
- Removal of rubbish, infested or decaying matter as well as crop
residues from around and in fields can often eliminate breeding
sites for pests
- Using seeds and planting materials which are free of weed seeds
and diseases
- Cleaning equipment before moving from infested areas
iiii. Crop Rotation:
- works on a limited number of pests, by replacing the host plant
with another crop for a period of time, allowing the pest
population to be reduced due to lack of a host. For this strategy
to work:
* The source of the pest must be within the field
* The pest can not be highly mobile
* The host range of the pest can not be wide
* The pest must not be able to survive in the soil for a long
period of time
iiiiii. Multiple cropping/Mixed Cropping:
- Increases the habitat for pest predators
- Limits the number of food plants for specific pests
iiiiiii Trap Cropping:
- Crops planted to attract pests away from the main crop
iiiiiiii. Soil Solarization:
- Uses a plastic tarp to cover the soil. This tarp heats up the soil
moisture to levels which are lethal to many fungi, nematodes,
weeds, weed seeds and other pest organisms
c. Advantages of cultural control methods
- Low cost (in most cases)
- Effects on non-target organisms low
- No Toxicity or residue problems
d. Disadvantages of cultural control methods
- Not always applicable
- May not be sufficiently effective
- Usually preventive in nature, so it requires planning
-May interfere with normal cultural operations
2. Plant Resistance
a. Definition: The use of species or varieties of plants that can grow and
produce despite the presence of the pest.
b. Methods
i. Use of crop varieties which resist pest attack or damage
ii. Resistant varieties may inhibit pest attack through toxic or repellent
compounds or through physical factors such as color or toughness
iii. Resistant varieties may have a high tolerance to pest damage
c. Advantages of plant resistance
- No harmful effects on natural enemies of pests or other non-target
organisms
- No toxicity or residue problems
- Can be a permanent solution
d. Disadvantages of plant resistance
- Pest resistant varieties or species of cultivated plants not available for all
pests
- Level of control may not be sufficient
- Discovery and development is slow
- Resistant varieties may not be agronomically acceptable
- Always preventative in nature and thus require forward planning
3. Biological Control
a. Definition: The use of predators, parasites, pathogens and competitors
to control pests.
b. Types
i. Conservation of a naturally occurring enemies of pests. Not
performing practices, such as use of a broad spectrum insecticide,
which could damage the naturally occurring biological control
organism. Also providing a favorable site for the development of a
biological control organism.
ii. Classical biological control: Introduction of a biological control
organism. Examples of this include introducing a predator of an insect pest or planting a cover crop or living mulch to compete with weeds
Augmentation: Applying the natural enemies of a pest as a biological
pesticide.
c. Advantages of biological control
- Low cost
- Has the potential to be permanent
- Not harmful to non-target organisms
- No toxicity or residue problems
d. Disadvantages of biological control
- Not always applicable
- Level of control may not be sufficient
- Research costs are high and may not produce results
4. Chemical Control
a. Definition: The use of toxic substances or pesticides to kill or repel
pests
b. Methods:
i. The decision to use a pesticide should be based upon:
- information obtained from monitoring/scouting
- knowledge of thresholds
- an awareness of potential benefits and risks associated with a
treatment
ii. Once a decision to use a pesticide has been made, several questions
should be thought through carefully:
- Is the pest you want to control listed on the pesticide label?
- Does the label state that it controls the pest or does it suppress the
pest?
- Are you familiar with the relevant university research and
recommendations?
- Is the recommended rate of application economical for your
operation?
- How toxic is the pesticide? dermally? orally?
- Is the pesticide a restricted use product?
- Does the pesticide have the potential to contaminate ground
water, even when label recommendations are followed?
- Will the use of this pesticide expose humans to health or safety
risks
- Will use of this pesticide threaten wildlife populations?
c. Advantages of chemical control
i. Applicable to most pests
ii. Curative in effect
iii. Grower may apply when and where required
iiii. Enable high levels of control of most pests to be achieved, so
unblemished produce can be produced
d. Disadvantages of chemical control
i. May harm natural enemies and other non-target
organisms
ii. Resistance to the pesticide can develop
iii. Often toxic to users and may present residue problems
iiii. Costs are high and recurring as control is not permanent
Activities
Discuss Hawaii examples of each type of control and field trips to sites which are unitizing these control methods
Resources
Agricultural Plant Pest Control, Chapter One: IPM on University of Nebraska Web site: http://ianrwww.unl.edu/ianr/pat/training.htm
Fenemore, P.G. 1982. Plant Pests and Their Control. Butterworths, Wellington, New Zealand. 271 pp.
Flint, M.L. 1990. Pests of the Garden and Small Farm. University of California Pub. # 3332. 276 pp.
Metcalf, R.L. and W. Luckmann. 1975. Introduction to Insect Pest Management. John Wiley & Sons, New York, NY. 587 pp.
Olkowski, W., S. Daar, and H. Olkowski. 1991. Common-Sense Pest Control. Taunton Press, Newtown, CT. 715 pp.
Watson, T.F., L. Moore, and G. W. Ware. 1976. Practical Insect Pest Management. W. H. Freeman and Co., San Fransisco. 196 pp.