1. PEST CONTROL

2. Green Revolution
Dramatically increased agricultural production brought about by “miracle” strains of grain
Usually requires high inputs of water, plant nutrients and pesticides
Typically yield more than other varieties if given optimum conditions but under suboptimum conditions they usually do worse than traditional varieties

3. Genetic Engineering
Involves removing genetic material from one organism and splicing it into the chromosomes of another
Has potential to greatly increase quantity and quality of food supply
Could, however, create superweeds or reduce native biodiversity

4. First Generation Pesticides
Mainly natural substances, chemicals borrowed from plants that had been defending themselves from insects for eons
Used up to the early 1900s until synthetic chemicals were produced (second generation pesticides)

5. Pests and Pesticides Biological Pests: Pesticide: Biocide:
Organisms that reduce the availability, quality or value of resources useful to humans
Pesticide:
Chemical that kills pests
Biocide:
Broad-spectrum pesticide that kills a wide range of living organisms
EX. Fumigants, such as ethylene dibromide, used to protect stored grain

6. Pests and Pesticides
The following are narrower spectrum agents that attack a specific type of pest.
Herbicides: Kill plants
Insecticides: Kill insects
Fungicides: Kill fungi
Rodenticides: kill rodents
Can also be defined by method of dispersal (fumigation) or their mode of action (ovicide)

7. Pesticide Types
Inorganic Pesticides: include compounds of arsenic, sulfur, copper, lead and mercury
Broad-spectrum, highly toxic, long lasting
Natural Organic Pesticides (botanicals): extracted from plants
Fumigants: small molecules that gasify easily and penetrate rapidly into a variety of materials

8. Pesticide Types
Chlorinated hydrocarbons: synthetic organic insecticides that inhibit nerve membrane ion transport and block nerve signal transmission
Organophosphates: reacts with the central nervous system
Carbamates: effect nervous system of pests more water soluble than chlorinated hydrocarbons
Microbial Agents and Biological Controls: living organisms or toxins derived from them used in place of pesticides

9. Pesticide Benefits
Important weapons in competition for food and shelter and to protect us from diseases and predators
Help control diseases by killing the vectors that transmit the diseases
Help protect crops by killing weeds, insects, etc.

10. Pesticide Problems Often kill nontarget species
Pest resurgence occurs: rebound of pest populations due to acquired resistance to pesticides
Pesticide Treadmill: occurs: a need for constantly increasing doses or new pesticides to prevent pest resurgence
Secondary Pest Outbreak: organisms that were not originally a pest become pests

11. Alternatives to Current Pesticide Uses
Biological Controls:
Use of natural predators, pathogens or competitors to regulate pest populations
Insect Birth Control:
Lab raised males are sterilized then released into the pest population

12. Alternatives to Current Pesticide Uses
Cultivation practices/Behavioral changes:
Rotate types of crops planted, adjusting plant times, planting trap crops
Genetic Engineering:
Speeds up the development of pest- and disease-resistant crop strains

13. Alternatives to Current Pesticide Uses
Sex Attractants:
Use of pheromones to lure and trap the pest
Hormones:
Disrupt an insect’s normal life cycle causing the insect to fail to reach maturity and reproduce

14. Alternatives to Current Pesticide Uses
Spraying Insects with Hot Water:
Worked well on cotton, alfalfa and potato fields and in citrus groves n Florida
Exposing Food with high-energy Gamma Radiation:
Such food irradiation extends food shelf life and kills insects, parasitic worms and bacteria

15. Ideal Pesticide Kills only target pest Harm no other species
Disappear or break down into something harmless after doing its job
Not cause genetic resistance in target organisms
Be more cost effective than doing nothing

16. Alternatives to Current Pesticide Uses
Integrated Pest Management (IPM)
An ecologically based pest-control strategy that relies on natural mortality factors, such as natural enemies, weather, cultural control methods and carefully applied doses of pesticides
Doesn’t give up pesticide use but tries to minimize the use, use as a last resort and avoid broad-spectrum pesticides

17. Regulating Pesticide Exposure
The EPA regulates the sale and use of pesticides under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), which mandates the registration of all pesticide products
Regulates all pesticides, reviews can take several years, most pesticides not use by the public
The EPA determines which pesticides will not pose significant risks to human health or the environment
The EPA sets “tolerance levels” in food under the Federal Food, Drug and Cosmetic Act (FFDCA)

18. Regulating Pesticide Exposure
The FDA and USDA enforce pesticide use and tolerance levels set by the EPA
The FDA and USDA can seize and destroy food shipments found to contain pesticide residues in violation of limits set by the EPA

19. Food Quality Protection Act
Emphasizes the protection of infants and children in reference to pesticide residue in food
FQPA requires a new safety standard – reasonable certainty of no harm – that must be applied to all pesticides used on food commodities

20. DDT Dichlorodiphyenyl trichloroethane
First synthesized chlorinated organic pesticide
Appeared to have low toxicity and was broad spectrum
Did not break down so it did not have to be reapplied often
Was water-insoluble (didn’t get washed away) and was inexpensive
Crop production increased, mosquitoes decreased

21. DDT
Rachel Carson published Silent Spring in1962 that made connection between DDT and non-target organisms by
Direct toxicity
Indirect toxicity (persistence in environment)—biomagnification and bioaccumulaiton

22. DDT Used as an insecticide
Has been found in regions not used because chemicals can circulate in the biosphere