agriculture, biotechnology & the future of food chap 10
TRANSCRIPT
Hunger
• lack of basic food required for energy and for meeting nutritional needs. Unable to lead a normal healthy life
• Root Cause of Hunger:
POVERTY
1.2 billion people live in absolute poverty:lack of income to meet the basic needs of food, shelter & clothing. ($1/day)
Food Sources: Livestock
• Chickens, Pigs, other fowl (US) (fyi)• ~7.6 billion chickens slaughtered 2008• 2009: 56 lb/capita• ~93 million pigs slaughtered 2008• 2012: 249 eggs consumed/person• Ruminants
– 4 chambered stomach– Cattle, sheep, goats, water buffalo, camel, llama – Cellulose Human Food– Produce ~100 million tons of methane,+ 30 million
through manure decomposition.
Cattle (US)• 1/1/09 94.5
million head of cattle
• 2008—27.3 billion lbs consumed
• 190 million lbs of milk produced
fyi
Food Sources: Aquaculture
• Production of food from aquatic habitats. Esp. important source of protein in Asia & Europe.
• Freshwater: fish grown in the same pond w/plants, or in rice fields. Waste acts as fertilizer. – carp, tilapia, crayfish, eels, catfish, salmon.
• Mariculture: ocean fish. Limited production Mussels and Oysters are grown on rafts (Portugal), artificial pilings (WA)
• Issues w/aquaculture– Confinement stresses fish– Spread of disease & parasites– Concentration of PCBs, heavy metals in
fishmeal fed to stocks, fish waste
Limits to Food Production
• Land available.
• Upper limit of production for amount of fertilizer applied.
• Climatic changes will tend to decrease yield.
• Water Availability
Without modern technology, little is sustainable.
“The Green Revolution”:
• Development of larger yields through breeding, tech, chemical use. 1950s– Norman Borlaug: Father of Green Revolution. Nobel Peace
Prize 1970. died Sept 2009
• Improved Irrigation Methods: Drip method to slowly add water.
• Chemical Pesticides & Herbicides• Increasing Available Land: including Hydroponics—
growth in fertilized water on artificial substrate.• Eating Lower on Food Chain: less production needed. • Genetic Modification: Similar to goals of the Green
Revolution, but by directly modifying DNA
Pest Control
• Major Pests: Insects, nematodes, bacterial & viral disease, weeds, vertebrates (rodents, birds)
• Pesticides: Herbicides, insecticides.– Broad Spectrum: Kills target pest as well as others– Narrow Spectrum: Kills only target pest.– End up in watersheds and waterways
DDT: Dichloro-diphenyl-trichloroethane• Excellent mosquito repellent• Silent Spring by Rachel Carson 1962• Banned in US 1972• Slow to break down• Fat-Soluble, biomagnifies in birds, fish.
• Natural Plant Chemicals• Integrated Pest Management
(IPM)– Natural Predators of Pests (ex:
ladybugs eat aphids that destroy roses)
– Plant diversity in crops– Insect bacterial diseases– Pheromones of insects– Narrow Spectrum Pesticides– Bt (bacillus thuringiensis) use-soil
bacteria used as insecticide
Bt toxins present in peanut leaves (bottom image) protect it from extensive damage caused by European corn borer larvae (top image).
http://en.wikipedia.org/wiki/Bacillus_thuringiensis
The Organic Movement and Locovores
• To Be Organic:– No pesticides on land for 3 years– No GMOs– No synthetic fertilizers or most pesticides– Animals: No hormones or antibiotics, access
to outdoors
• Locovore: – buying food grown within 100 miles of home– CSAs— Fernbrook
Genetically Modified Organisms– Placing genes of one species into another.– Pros:
• Bred w/better nutrients (golden rice)• Durability & production (tomatoes, salmon, papaya)• Built-in pest resistance (Bt, Roundup Ready)
– 93% of US soy & cotton, 86% US corn
– Cons:• Decreasing biodiversity, interbreeding w/wild crops• Possibly creating super resistance in pests/weeds• Allergies• Terminator Gene
+Prevents spread of genes since seeds can’t reproduce
– Creates monopoly for developers