Insects and People: Insects and Agriculture

Insects As Pests

  • In the U.S. there are about 100,000 insect species
    • around 200 serious pest species + 4-500 occasionally serious
  • About 3,500 worldwide serious insect pest species
  • Most of these are agricultural pests.
  • Agricultural Entomologists: Study how we can prevent as much crop damage from insects as possible Other issues like resistance

Agriculture in NC

  • Worth $7-8 billion at the farm gate, $45-50 billion on the plate
  • Number one state in tobacco, sweet potatoes, & turkeys
  • Second in hogs, farm-reared trout, Christmas trees, and cukes
  • Not bad in poultry, eggs, greenhouse and nursery, turg, peanuts, etc.
  • We’ve come a long way since tobacco

Pests of Crops

  • About half of all insect species are phytophagous (herbivores)
  • Insects eat about 1/3 of all crops grown, despite attempts to control them
  • Where do they come from?
    • Monocultures and confined livestock
    • About 40% of serious pests are foreigners
  • What do they look like?
    • Only 9 of the 30+ insect orders have plant feeders
    • Most are chewers, some mine, bore, girdle, or suck (disease vectors)
  • When is plant feeding a problem?
    • Depends on which pieces and parts are eaten
    • Economic Threshold—The insect density that it is wise to treat your crops to save money on the damage
    • Cost of treatment is less than the damage
    • Economic Injury Level—The density of insects that you are actively losing money from insect damage

 

 

Pests of Livestock

  • Biters, buzzers, and stingers: annoyance
    • Flies
    • Lice, fleas, ticks, and mites
    • Fewer pounds, eggs, quarts, babies, belts, etc
  • Myiasis
    • screw worms, cattle grubs, bot flies
  • Vectors of disease agents
  • Veterinary Entomologists—Study how insects negatively impact animal well-being and health

Pests of Pets

  • Fleas and Ticks
  • Mosquitoes and heartworm
    • Agent: roundworm
    • Vector: mosquito
    • Target: mostly dogs, some cats, ferrets, otters, occasionally humans
    • Distribution: worldwide
    • Pathology: heart and lungs main targets
    • Treatment: various drugs, including arsenic compounds