Corn

介绍了corn的种植历史，Nearly 9,000 years ago，first domesticated from teosinte.

Corn

• Nearly 9,000 years ago
  • first domesticated from teosinte
• Over the next 4,700 years
  • farmers bred it into a staple crop
  • Maize spread throughout the Americas
  • took on an important role
• Europeans first arrived in America
  • soon crossed the Atlantic
  • a popular grain in many European countries
• Early 1800s
  • Types
    • varying size and taste
• 1850s
  • Unique varieties
    • difficult for train operators to package
    • difficult for traders to sell
  • Standardized crop
    • Be encouraged
• 1893
  • World’s Fair
    • James Reid’s yellow dent corn won the Blue Ribbon
• 1894-1943
  • Yellow dent corn
    • Swept the US
• 1944-1972
  • numerous corn concoctions
    • Low-cost sweetener
    • Thickening agent（稠化剂）
    • Animal feeds
  • Cornstarch（玉米淀粉）
• Today
  • Cultivated corn
    • 40%
      • humans eat
    • 60%
      • supports consumer good industries （食品消费工业）
• A global phenomenon
• Views
  • Europeans
    • Shunned
    • Bias
      • The source of physical and cultural differences between them and the Mesoamericans
    • Attempted to cultivate European crops in American soil
      • Quickly failed
    • Had to expand their diet
    • Found the crop to their taste
  • indigenous societies （原住民）
• Harms behind its boom
  • Polluted water
  • agriculture-related carbon emissions
  • contributor to diabetes and obesity
  • monoculture farming （单一耕作农业）
  • a maze of unsustainability
• Demand for meat and corn feed
• inexpensive meat production
• Cheapest feed
• Policy
  • limited the amount of corn farmers
  • massive grain sales to the Soviet Union
• An attractive crop to American farmers
• Technological developments of World War II
  • Mechanized harvesters
    • High efficiency
  • NH₄NO₃
  • Chemical explosive ammonium nitrate
    • Synthetic fertilizer
      • Planting density
• adaptability
• The goddess who created agriculture
• Corn Mother
• Features
  • larger cobs
  • edible kernels
• a versatile material
• barely edible
• Teosinte
  • a grass native to Mesoamerica
  • feature
    • seeds
      • rock-hard
    • husk （外壳）
      • fibrous