1. Pesticides and Pest Control

2. Key Concepts  Types and characteristics of pesticides  Pros and cons of using pesticides  Pesticide regulation in the US  Alternatives to chemical pesticides

3. Pests  Compete with humans for food  Invade lawns and gardens  Destroy wood in houses  Spread disease  Are a nuisance  May be controlled by natural enemies 50-90% of pests are controlled this way  May be controlled by natural enemies 50-90% of pests are controlled this way

4. Pesticides: Types  Insecticides-kills insects  Herbicides-kills weeds  Fungicides-kills fungus  Rodenticides-kills rodents  Nematocides-kills worms

5. First Generation Pesticides  Primarily natural substances  Sulfur, lead, arsenic, mercury  Plant extracts: nicotine, pyrethrum  Plant extracts are degradable

6. Second Generation Pesticides  Primarily synthetic organic compounds  630 biologically-active compounds  Broad-spectrum agents-toxic to many species  Broad-spectrum agents-toxic to many species  Narrow-spectrum agents-effective on Only a few select species  Narrow-spectrum agents-effective on Only a few select species  Target species-1 species  Nontarget species

7. Case for Pesticide Use  Save human lives  Increase supplies and lower cost of food  Work better and long shelf lives  Health risks may be insignificant compared to benefits  Newer pesticides are becoming safer  New pesticides are used at lower rates

8. Characteristics of an Ideal Pesticide  Kill only target pests  Harm no other species  Break down quickly and naturally  Not cause genetic resistance  Be more cost-effective than doing nothing

9. The Case Against Pesticides  Genetic resistance:5-10 years insects, more slowly In plants. 1000 currently have resistance  Genetic resistance:5-10 years insects, more slowly In plants. 1000 currently have resistance  Can kill non-target and natural control species  Can cause an increase in other pest species  The pesticide treadmill  Pesticides do not stay put: 2-5% remain  Can harm wildlife-DDT birds, runoff kills fish  Potential human health threats

10. The Pesticide Treadmill When a pesticide doesn’t work then 1.Apply more often 2.Apply larger doses 3.Use new chemical This is harmful because insect population is larger and crop production is down Costs 4-6 billion dollars per year

11. Pesticide Regulation in the United States  Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)- all commercial pesticides must be approved by EPA  Tolerance levels-determined by EPA  EPA Evaluation of chemicals- doesn’t have To be complete before license is granted  EPA Evaluation of chemicals- doesn’t have To be complete before license is granted  Inadequate and poorly enforced  Food Quality Protection Act (FQPA)

12. Other Ways to Control Pests  Economic threshold  Adjusting cultivation practices: crop rotation  Use genetically-resistant plants: GMO’s  Biological pest control: Bring in predators  Biopesticides: Botanicals or Microbes  Ionizing radiation

13. Insect Control Genetic Engineering Sterilize males so Ineffective when mate Ex) Screw worm fly, Tetsie fly High cost and large Number to be effective Ionizing Radiation Irradiated foods: exposing to lose dose of radiation delays sprouting, kills pests, and extends shelf life Food itself is NOT radioactive Ionizing Radiation Irradiated foods: exposing to lose dose of radiation delays sprouting, kills pests, and extends shelf life Food itself is NOT radioactive

14. Integrated Pest Management  Ecological system approach  Reduce pest populations to economic threshold but doesn’t eradicate them  Field monitoring of pest populations  Use of biological agents  Chemical pesticides are last resort  Increases production while lowering costs

15. Effects of IPM