Fundamental Principles of Pest Control

1. Fundamental Principles of Pest Control Dr. Richard M. Houseman Department of Entomology University of Missouri-Columbia

2. Objectives • Unit 1: pg. 1-39 “Applying Pesticides Correctly” • Pests • Identification and Damage • Insects • Plant Diseases • Weeds • Vertebrates • Pest Management • Pesticides • Mode of Action

3. Core Manual • ‘Learning Objectives’ • Clues to what is important • ‘Terms to Know’ • Definitions of common words • ‘Test Your Knowledge’ • Example test questions

4. Pest Management (pg.5) Objectives • Prevention = keep from becoming a problem • Suppression = reducing to an acceptable level • Eradication = destroying an entire pest population

5. Management Strategies • Mechanical • Exclusion/removal • Heat/cold • Biological • Natural enemies, microbials • Pheromones/hormones • Cultural • Tilling, burning, mowing, flooding • Crop rotation, trap crops • Planting/harvest timing

6. Management Strategies • Sanitation • Eliminate breeding sites • Remove pathogens/sources • Disinfect equipment/tools • Host Resistance • Using disease-resistant varieties • Genetics • Manipulate host resistance • Sterility in pest

7. Management Strategies • Chemical • The use of natural or synthetic substances that directly cause the death, repulsion, or attraction of pests. Considerations • Mode of Action • Persistence • Non-target effects • Resistance

8. Mode of Action • Mode of Action • The way a chemical kills a pest. Examples: • Repellents, poisons, eradicants, systemics

9. Persistence • Persistence • The length of time a chemical is active after being applied. Categories: • Non-Persistent • Kills the pest, breaks down in a relatively short period of time • Persistent • Residues remain active for period of time after application

10. Non-Target Effects • Non-Target Effects • Pesticide effects on non-pest organisms. Potential risks: • May kill beneficial organisms • May create new pests • Ex.-Killing natural enemies of a non-pest.

11. Resistance • Resistance • Lessening of the effectiveness of a pesticide for reducing the pest population Principles: • Chemicals kill only susceptible pests • Survivors pass traits for survival to their offspring • Resistance develops over generations

12. To promote: Use same pesticide repeatedly Use over large areas Use highly residual chemicals To limit: Rotate pesticides Target applications Use persistent chemicals wisely Resistance

13. Pests (pg.3) • A Pest is any unwanted organism • Based on what organism does, not on what they are. • Compete for food or water • Cause injury, disease, or annoyance

14. Pests (pg.3) Types of Pests • Continuous = nearly always present • Sporadic = occasionally present; migratory/cyclical • Potential = not normally pests, require control only in certain situations

15. Pest Identification (pg.3) • How to Identify? • Physical features • Damage or Symptoms • Why Identify? • Pests differ in their habitats, behavior, life cycles, and susceptibility to control methods.

16. Insect & Insect-like Pests (pg.6) • Physical Features • Segmented bodies • Jointed appendages • Exoskeleton made of chitin • Bilateral symmetry

17. Insects • Three body regions (pg.6) • Head • 1 Pair of antennae • Various mouthparts • Thorax • 3 pairs of legs • 2 pairs of wings • Abdomen • Body systems

18. Insects • Life Cycle (pg.7) • Metamorphosis • None Only change is size • Gradual Egg, nymph, adult • Incomplete Egg, nymph, adult (H2O) • Complete Egg, larva, pupa, adult

19. Insect-like Groups (pg.8) • Arachnids • Spiders, mites, ticks • 2 regions, 8 legs • Crustaceans • Pillbugs • 3 regions, >8 legs • Chilopods • Centipedes • Many regions & legs • Diplopods • Millipedes • Many regions & legs

20. Insect-like Groups • Nematodes • Microscopic roundworms • Mollusks • Slugs, snails Look like insect larvae • Non-segmented • No metamorphosis

21. Insect Pests of Plants (pg.10) • Types of damage • Leaf eating • Plant-sucking • Internal feeding • Stem boring • Root feeding

22. Pests of Animals (pg.11) • Types of damage • Stinging • Biting • Blood sucking • Toxin injecting

23. Insecticides (pg.15) • Modes of Action • Repellents Keep insects away from an area or host • Disrupters Interfere mechanically with body function • Poisons Deactivate biological systems in the body • Stomach = must be eaten • Contact = must be touched

24. Plant Pathogens (pg.16) • Plant Disease • Any condition that causes a plant to function or appear different from normal

25. Plant Diseases (pg.16) • Plant Responses to Disease Agents • Overdeveloped tissues ie. galls, leaf curls, swelling • Underdeveloped tissues ie. stunting, lack of chlorophyll • Death of Tissues ie. leaf spot, wilting, blight, cankers

26. Plant Diseases • Pathogens include: • Fungi • Bacteria • Viruses • Mycoplasmas

27. Fungi (pg.16) • Feed on other organisms • Most are beneficial • Decomposers • A few parasites • Feed on living plant tissues • Reproduce by spores • Microscopic, resistant stage

28. Fungi • Symptoms • Soft rot of fruit • Rusts, smuts • Curling, powdery mildew of leaves • Spots on leaves

29. Bacteria (pg.17) • Microscopic • Symptoms • Blights, spots , rots • Reproduce by cell division

30. Viruses (pg.17) • Sub-microscopic • Symptoms • Abnormal growth, mosaics • Reproduce inside host cell • Vector transfer

31. Mycoplasmas (pg.17) • Smallest living things • Plant-feeders • Symptoms • Yellow, stunting • Reproduce independently • Insects, mites, grafting

32. Fungicides & Bactericides • Modes of Action (pg.20) • Protectants • Applied before or during initial infection • Eradicants • Applied after infection • Systemics • Internal transport to all tissues of plant

33. Weeds (pg.21) • A weed is any plant growing where it is not wanted. Effects: • Compete for resources • Contaminate harvest • Harbor pests or release toxins • Look ‘bad’

34. Weeds • Development (pg.21) • Seedling • Vegetative Producing leaves, stems, roots • Reproductive Producing flowers, seeds • Maturity

35. Weeds • Life Cycles (pg.21) • Annuals = one year • Biennials = two years • Perennials = more that two years

36. Weed Identification (pg.22) • Grasses • Narrow, parallel veins, round stems • Sedges • Narrow, parallel veins, triangular stems • Broadleaves • Fan-like, branching veins

37. Herbicides (pg.25) • Modes of Action • Contact • kills parts of plant the chemical touches • Translocated • absorbed and distributed throughout the plant • Selective • kills only undesireable plants • Non-selective • kills all plants in an area or or

38. Herbicides

39. Herbicides (pg.26) • Modes of Action (cont’) • Foliar • Applied to leaves of the weed (foliage) • Soil • Applied to the ground around the weed Example: 2,4-D is a foliar-translocated-nonpersistent-selective or

40. Vertebrates (pg.29) • Have backbones • Many potential pests • Various situations and impacts. • Eat crops, kill livestock, transmit disease, contamination, etc.

41. Poisons (pg.30) • Few pesticides available • Rodenticides: most commonly-used • Piscicides • Avicides • Usually highly toxic to humans

42. Summary • Identification of the pest and an understanding of its biology is important. • The best pest management programs combine all of the available control tactics. • When using chemicals, it is important to understand their mode of action, persistence, risk of resistance, and their effect on non-target organisms.