Your SlideShare is downloading. ×
Als 3153 Class 15
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Als 3153 Class 15

643

Published on

1 Comment
1 Like
Statistics
Notes
  • very useful for me.
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
No Downloads
Views
Total Views
643
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
32
Comments
1
Likes
1
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Introduction to Insects
  • 2. Phylum Arthropoda (jointed appendages, exoskeleton, etc.) • Class Insecta (most numerous and diverse group of organisms) • Class Arachnida • Class Crustacea • Etc. (centipedes, millipedes, etc.) Spiders – often beneficial as predators Mites – some plant pests, some predators
  • 3. Insects vs Arachnids (Mites, Spiders)
  • 4. Insect Life Cycles • 1. Simple metamorphosis • 2. Complete metamorphosis • 3. Some exceptions • #1 and #2 apply to most agricultural pests
  • 5. Simple Metamorphosis Egg Nymphs Adult – has full-size wings, functional reproductive system
  • 6. Simple Metamorphosis Nymphs InstarInstar Molt Molt
  • 7. Simple Metamorphosis Egg Nymphs Adult – has full-size wings, functional reproductive system Usually 4-6 instars, resemble adults, smaller size Same food and environment for nymphs and adults
  • 8. Complete Metamorphosis Egg Pupa Larva – several instars, important feeding stage Adult – very different from larva Corn Earworm
  • 9. Complete Metamorphosis • Life stages are important because ecology, food habits, and management of different stages can be different • Example: butterflies and moths • Larva – feeds as damaging caterpillar • Adult – beneficial as plant pollinator
  • 10. Survey of insects – Major groups (orders) of ag pests or beneficial predators and parasites • Beneficial insects: • Predators, parasites • Pollinators • Recyclers of OM
  • 11. Survey of insects – Major groups (orders) of ag pests or beneficials • Dragonflies • Orthoptera and relatives (mantids, roaches) • Thrips • True bugs (Hemiptera) • Piercing-sucking insects (Homoptera) • Beetles • Nerve-winged insects (Neuroptera) • Butterflies and moths • Bees, wasps, and ants • Flies • Etc.
  • 12. Survey of Insects • Dragonflies --- beneficial predators of flying insects • Praying mantids --- beneficial predators • Roaches --- recycling in some ag systems • Grasshoppers, Crickets --- can be serious ag pests
  • 13. Tawny Mole Cricket
  • 14. Thrips Thrips palmi
  • 15. Thrips • Almost microscopic in size, fringed wings • Beneficial pollination in flowers • Most are plant pests • Some carry plant viruses
  • 16. Virus Vectors • Vector = carrier of virus • Viruses in plants • Transmitted by insects, etc. • Vector feeds on infected plant acquires virus feeds and passes virus to other plants
  • 17. True Bugs • Squash bug • Note typical appearance
  • 18. True Bugs • Piercing-sucking mouthparts • Some important pests, e.g., stink bugs • Some predators
  • 19. Piercing-Sucking Insects • Piercing-sucking mouthparts to feed on plants • Formerly Homoptera, often included with true bugs • Many important plant pests • Some transmit viruses • Aphids, cicadas, whiteflies, scale insects, leafhoppers, etc…
  • 20. Green Peach Aphid • Very abundant as plant pests
  • 21. Whitefly Adult • Common underneath leaves
  • 22. Sooty Mold - Silverleaf • Important sign of whiteflies, etc…
  • 23. Beetles • Pepper Weevil
  • 24. Beetles • Very many species • Many pests – weevils, larvae of some types are grubs or wireworms • Many beneficials – Lady beetles, ground beetles, tiger beetles
  • 25. Nerve-Winged Insects (Neuroptera) • Brown Lacewing
  • 26. Lacewing Larva Eating Whiteflies • Beneficial predators
  • 27. Butterflies and Moths • Pests – many kinds of caterpillars • Beneficial as pollinators
  • 28. Bees, Wasps, Ants • Beneficial as pollinators • Many are important as predators and parasites • Many different kinds of wasps, most nearly microscopic • Parasitoids – microscopic wasps, lay eggs in body of pest (e.g., caterpillar), or even in egg
  • 29. Flies • Many different kinds, difficult to distinguish – different flies do different things: • Important pests of livestock • Beneficial as pollinators • Beneficial as predators • Some are parasitoids • Some are plant pests (leaf miners)
  • 30. Leafminers • Larvae of some flies, some moths
  • 31. Many Important Pests of Livestock • Flies, Lice, Fleas, etc…
  • 32. Important Insect Relatives • Mites -- some beneficial predators • Mites – some livestock pests • Mites – some plant pests • Spiders – Very important as predators (much underrated) in agroecosystems
  • 33. Mite Damage on Leaf
  • 34. Spider Mites • Note characteristic webbing
  • 35. Management of Insect Pests
  • 36. Insecticides and Acaricides • +++ effective, detailed knowledge of pest biology not needed • +++ reliable, fast-acting • +++ quick response to emergency situations • - - - non target effects • - - - $ and energy costs • - - - high expectations
  • 37. Biological Control • Control by living organism or natural product of living organism • Hyperparasitism Caterpillar Tachinid fly Parasitoid Wasp
  • 38. Biological Control -- Two Approaches • Introduced = add control agents to ecosystem (many good examples with introduced pests) • Introduced: classical (new agent) vs augmentation (agent already present) • Natural = favor increase of naturally occurring control agents (manipulate environment, cropping systems)
  • 39. Biological Control Many possible organisms: • Predators (often not specific) • Parasites • Diseases (parasites) Fungi Bacteria Viruses Parasitoids (often highly specific) Entomopathogenic nematodes
  • 40. Host Plant Resistance • Interfere with host finding, feeding, pest nutrition, timing of life cycles, etc… • Hairs on leaves, sticky, etc. • Alkaloids in plants deter insects • Crop cultivars/genotypes selected for resistance to pests
  • 41. What is Biological Control and What Is Not ???
  • 42. What is Biological Control? • Predators • Parasites • Diseases
  • 43. What is Biological Control? • Predators • Parasites • Diseases • Bacterial disease of insects caused by Bacillus thuringiensis (BT)
  • 44. What is Biological Control? • Bacterial disease of insects caused by Bacillus thuringiensis (BT) • Allow bacteria to produce spores with toxin in lab, isolate BT toxin, and spray it on pests
  • 45. What is Biological Control? • Bacterial disease of insects caused by Bacillus thuringiensis (BT) • Allow bacteria to produce spores with toxin in lab, isolate BT toxin, and spray it on pests • Transgenic plants that produce BT toxin (Bt corn, Bt cotton)
  • 46. What is Biological Control? • Resistant plants as biological control agents • Plants with alkaloids • Pyrethrum = natural plant alkaloid
  • 47. What is Biological Control? • Resistant plants as biological control agents • Plants with alkaloids • Pyrethrum = natural plant alkaloid • Isolate pyrethrum from plants and use it
  • 48. What is Biological Control? • Resistant plants as biological control agents • Plants with alkaloids • Pyrethrum = natural plant alkaloid • Isolate pyrethrum from plants and use it • Make synthetic pyrethrum • Pyrethroid = pyrethrum analog, similar chem structure
  • 49. Environmental Heterogeneity • Crop genetics (uniform genotypes vs mix) • Vegetation diversity vs pest dispersal • Vegetation diversity as reservoir for natural enemies
  • 50. Plant Health • +++ Healthy plant can withstand some insect damage • - - - High N can increase insect growth and reproduction
  • 51. Attractants and Repellents • Attractant, e.g., pheromone (sex or aggregation) useful for: • Sampling and monitoring (important use for quarantine detection, regional monitoring) • Attracting insects to traps • Confusing normal life processes and patterns
  • 52. Cultural Practices • Crop Rotation • Weed control of virus hosts • Sanitation and cleanup of crop residues (affected overwintering of boll weevil) • Timing of planting dates (winter wheat, Hessian fly) • Others (sterile males, etc.)
  • 53. For most effective insect management, usually need to know biology and habits of individual insect pests
  • 54. References • Text: Ch 10, pp. 201-208; Ch.11, pp. 219-222. • Metcalf C.L., W.P. Flint, and R.L. Metcalf. 1962. Destructive and Useful Insects. McGraw-Hill, NY. • Metcalf, R.L., and W.H. Luckmann. 1994. Introduction to Insect Pest Management. John Wiley & Sons, NY. • Images from UF Dept. Entomology & Nematology – Featured Creatures: • http://creatures.ifas.ufl.edu

×