lec 29- The green Revolution Flashcards
what was the first, second and third agricultural revolution?
first- transition from hunting to gathering
second- first machines during industrial revolution
third- “green revolution” addition of biotechnology into agriculture
what was the green revolution?
it was the movement to increase crop yields by:
-fertilizers
-pesticides
-high yield variety seeds
-irrigation
etc.
when did the green revolution begin?
from the 1960s to 1980s
what did an increase in crop yield do?
increase the worlds population
what environmental harm does intensification of agriculture cause?
-pollution from synthetic fertilizers
-pollution from synthetic pesticides
-water depletion from irrigation
-fossil fuels used for power production
who was the father of the green revolution?
-Norman Borlaug
what were some problems that occurred to plants when plants were planted at high density?
-a lot of straw biomass instead of larger and more seeds
-plants shaded each other, resulting in excess elongation
-plants fell over in wind and rain (lodging), resulting in crop loss
what were the solutions to the problems of plants that were in high density ?
-develop by breeding semi-dwarf wheat and rice varieties which have limited straw sink, strong, large, and more seeds, no lodging, and are easy to harvest.
-natural rare variants solved the problems
what was the nature of the variant for plants?
GA synthesis mimics shade avoidance response and plant growth, but it allows dwarf alleles to come into play, creating small wheat and rice.
do humans have to increase food production to support our growing population?
yes, we need to increase the food population by 70% in the next 40 years.
what are the 4 reasons why big increases in production are hard to achieve?
- there’s little unharmed land to bring into production
- no more water
- little benefit from additional fertilizer
- the easiest targets for breeding of key crops have been done
how is marker-assisted breeding of crops an improvement to the GR?
-allows selection based on genotype rather than phenotype
-faster
-smaller populations
why are genetically modified (GM) crops seen as taboo?
because of fear and politics doesn’t like it
what are alternatives to GM crops?
-orphan crops (underutilized)
-can be used with GM to improve productions
what are types of orphan crops?
-yam
-millet
-cowpea
etc.
