Pests and Pest Control

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Chapter 17

• Pests and Pest Control

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Pest Control Pesticides
Worldwide, 37 billion were spent on
pesticides. They protect crops, but what are the
drawbacks?
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Chemical Control Successes

• First Generation Pesticides toxic heavy metals
• Second Generation Pesticides synthetic organic
  chemicals
• DDT toxic to insects, non-toxic to humans,
  cheap, persistent

4
Chemical Control Problems

• Resistance
• Secondary Outbreaks
• Human Health cancers, acute poisoning
• Environmental Effects non-target organisms,
  persistence

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Chemical Control DDT
DDT made its way up the food chain and killed
animals that people cared about
Biological Magnification
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Alternative Methods

• Cultural
• Natural Enemies
• Genetics
• Natural Chemicals

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Alternative Methods Cultural

• Cleaning remove things that entice pests
• Insect screens keep pests out of the house
• Crop Rotation avoid a buffet for insects
• Lawn Care leave the grass 3 long, avoid
  plants that attract pests (roses), allow
  diversity in the lawn

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Alternative Methods Natural Enemies
Predators and parasites can often be used to help
control a pest. Examples include ladybugs for
scale insects, parasitic wasps for caterpillars,
Brazilian weevils for water hyacinth
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Alternative Methods Genetics

• Chemical barriers through breeding
• Physical barriers through breeding
• Biotechnology introducing novel genes into an
  organism

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Alternative Methods Natural Chemicals

• Use an insects own pheromones against it
• juvenile hormone
• mate attractants

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Socioeconomics Pesticides
Pesticides will only be economical if they keep a
pest below a critical threshold. If the pest is
already below the threshold then pesticides
should not be used.
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Socioeconomics Integrated Pest Management
Crop rotation, polyculture, destruction of crop
residues, predator populations, careful timing of
planting and fertilizer
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Socioeconomics Organic Food

• Grown without synthetic fertilizers or
  pesticides
• Higher cost
• The market share is growing
• Certification is an issue

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Public Policy

• Federal Insecticide, Fungicide, and
  Rodenticide Act covers manufacture, use,
  and sale of pesticides
• Food Quality Protection Act standards for
  chemicals on foods
• Developing Countries informed permission for
  selling pesticides banned in the US to other
  countries

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Future Policy

• Reduce pesticide use
• Promote biological control
• Use of IPM

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Summary

• Pest Control pesticides
• Chemical Control successes, problems, DDT
• Alternative Methods cultural, natural enemies,
  genetics, natural chemicals
• Socioeconomics pesticides, integrated pest
  management, organic food
• Public Policy current policy, future policy