The Green Revolution Flashcards
The Population Bomb
by biologist Paul R. Ehrlich,
“The battle to feed all of
humanity is over … In the
1970s and 1980s hundreds of
millions of people will starve
to death in spite of any crash
programs embarked upon
now.”
problem to fufill food for all
NORMAN BORLAUG & THE GREEN REVOLUTION
Norman Borlaug
“The man who saved a billion lives”
Plant geneticist, “Father of the Green Revolution” Nobel Peace Prize 1970
THE GREEN REVOLUTION
Development of modern, high yielding varieties wheat & rice in 1950-60s
* International Center for Wheat and Maize Improvement in Mexico (CIMMYT);
* International Rice Research Institute, Philippines (IRRI).
Production of dwarf, high-yield, disease-resistant crop varieties
* Dwarfing genes, shorter, stiff strawed varieties - more energy for grains
* Multiline varieties for increased disease resistance
* Better response to fertilizer
* Introduced to Mexico, Pakistan and India, later to Asia and Africa
GREEN
REVOLUTION
Improvements in tropical beans, cassava, root crops, millets in the 1980s
Declines in food prices worldwide
CHANGES TO FARMING PRACTICES
Dramatic changes to agriculture in since 1950s
* New technologies and mechanisation
* Increased chemical use (pesticides, fertilizers, water)
* Government subsidies to maximize production
* Reduced labour demands, fewer farmers producing more
Increasing monocrops for market
ENVIRONMENTAL EFFECTS OF FERTILIZERS
Excess nitrogen and phosphorus from agricultural fertilizers cause an overgrowth of algae (algal bloom) which consumes oxygen and blocks sunlight from underwater plants, making it impossible for aquatic life to survive
SUSTAINABLE INTENSIFICATION
Producing more food from the same area of land while reducing the environmental impacts
GENETICALLY ENGINEERING CROPS
Genetic engineering is the direct manipulation of an organism’s DNA.
Genetically modified organism: plants, animals or microorganism in which the genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination (biotechnology).
Transgenic organism: organisms that have undergone heritable genetic changes by transformation with foreign DNA.
Gene editing: manipulation of the genetic material of a living organism by deleting, replacing, or inserting a DNA sequence (highly specific)
GENETICALLY MODIFIED ORGANISMS
Genetically modified using recombinant DNA technology
1. Agrobacterium tumefaciens
2. Gene gun
Increased rate of ‘selection’
Transgenic - Open sexual
recombination outside ‘species’ barrier
TYPES OF GMOS
-
Herbicide resistance
Monsanto’s Roundup ready, soy, maize, canola, alfalfa, sugar beets, cotton(glyphosate-resistant) -
Stress resistance (drought, salinity, insects, pathogens)
* Pests: BT plants (transgenic inclusion of Bacillus thuringiensis gene
which kills Lepidoptera larvae (European corn borer).
Cold: ‘antifreeze’ gene from Arctic flounder introduced into strawberries -
Nutritional content
Golden rice (beta-carotene)
HERBICIDE RESISTANCE
Glyphosate resistant crops
(broad spectrum herbicide)
Prolonged use resulted in pesticide- resistant weeds
Greater quantity of pesticides overall
Environment: run-off into ecosystem
**Health: **glyphosate becomes highly toxic to the kidneys when mixed
with arsenic and cadmium in soil
PATHOGEN RESISTANCE
Ring spot virus decimated Hawaii’s
papaya crop in 1950s and 1990s
Rainbow papaya – ring-spot resistant
1st GMO fruit to be grown in commercial production (1998)
2014: Hawaii harvested >23M lbs of
papaya
in north america gmo does not need to be lebbeled(by law)
PRINCIPLE OF SUBSTANTIAL EQUIVALENCE
1993: formulated as a food safety policy by the Organisation for Economic Co- operation and Development (OECD).
Substances (proteins) added through GM are treated as ‘food additives’ if they are significantly different in structure, function or amount than substances currently
found in food
* If a GM food does not contain substances that are significantly different from those
already in the diet, it can be considered as safe as its conventional equivalent (no premarket approval required)
Subject of considerable criticism and comment (Royal Society of Canada, 2001); argued to be approach is subjective and inconsistent
Unlike the EU, GM foods in the US and Canada do not require special labeling to notify consumers
GMOS IN CANADA
1st GM foods introduced in 1996
As of 2019, >140 GM foods are
permitted for sale
4th largest producer of GM crops
(canola, corn, soy, sugar beets, alfalfa)
TRANSGENIC FISH FOR SALE
2018: Canada approved the 1st transgenic animal for sale and human consumption globally
>4.5 tonnes of GM Atlantic salmon sold
AquaBounty AquAdvantage Atlantic salmon—a GM fish that grows to market size in half the time as
conventionally farmed salmon.
Combines a growth hormone gene from a Chinook salmon with a gene promoter from ocean pout, enabling the salmon to produce growth hormones all the time.
Require ~25% percent less feed to grow to maturity
GENE EDITING
CRISPR-Cas9: adding, deleting or replacing segments of an organism’s DNA using RNA ‘guide sequences’ to target specific areas of the genome and the Cas9 enzyme
to cut DNA at the targeted location.
Allows for direct manipulation of
organism’s own DNA; no ‘foreign’ DNA.
Faster, cheaper, more accurate, and more efficient than other GM methods
GENE EDITING DOGS
GE to treat dogs with condition similar to Duchenne muscular dystrophy
First use of CRISPR-technology on a large mammal
CRISPR to correct dystrophin protein
levels in skeletal and heart muscle;
improved muscle histology
Pros of GMO Debate
- Increased nutritional content
- Decreased need for pesticide
- Increased crop yields
- Immunity to pests, fungal/viral
pathogens - Improve fertilizer–use efficiency, or
nitrogen-fixing - Storage/transport
- Expand agricultural zones
Cons of GMO Debate
- Glyphosate-resistant weeds & increased pesticide use
- Reliance on GM seeds and Ag Chemicals (food sovereignty)
- IPR, seed saving, traditional management
- No consistent $$$ benefits to farmers
- No scientific consensus on the question of GM food safety
- Increased monocrops, less diversity
- Cross-pollination of GM and non-GM plants
SUSTAINABLE AGRICULTURE
Ecosystem approach to farming
* Reducing tilling and erosion (wind breaks, no-till)
* Replenishing soil nutrients through crop rotation and composting (not synthetic fertilizers)
* Reduced-volume irrigation, drought-resistant crops
* Reduced energy and mechanization
Protect environment, public health, human communities, and animal welfare
* No non-therapeutic antibiotics or arsenic-based growth promoters.
* Livable wage and safe, fair working conditions
* Treat animals with care and respect (move freely, engage in instinctive behaviors, consume a natural diet)
