quiz 3 Flashcards
origins of griculture
multiple/independent
developed 9000-10000 years ago (carbon dating or pollen grains)
many civilizations begun practicing agriculture at the same time, however, it was not connected
hunter gatherers began watering plants which became planting - then they grew enough food for themselves, eventually having surplus which created storage
agricultural impacts on civilization
increased populations, war, incentivized to become less nomadic, diversification of activities and ideas, development of tech, increased trade
agricultural impacts on human/environmental health
increased standard of living, selective breeding, trade, sanitation issues, decreased biodiversity, conflict, deforestation, malnutrition
domestication
genetic modification of a species through human intervention
a single plant can create many crops (brassica oleracea) – wild mustard into brussel sprouts, cabbage, cauliflower, broccoli, etc
selective breeding
method of domestication hybridization - reproduction between two varying species
can choose seeds from plants of good quality for planting next years crops
manually pollinate using pollen from known donor
why are some species more available for domestication
some plants have incredibly toxic genes that would be dangerous to try and domesticate
other plants have toxic genes that can be bread out of them
almond vs acorn
why are centers of origin of different crops important
pre/post columbian dietary shifts
brought corn, potatoes and tomatoes and peppers to europe
brought wheat to west indies
genetic engineering
human manipulation of selected genes (individual)
able to produce multi-cellular individual in which all cells have the change
have the ability to pass it onto offspring
dangers of relying on limited crop varieties
they will be more vulnerable to pests and pathogens
methods of genetic engineering
engineered plasmid (must have promoter, stop code, gene of interest, and antibiotic resistance gene)
antibiotic resistance gene - helps scientists and farmers to know if their gene is present in offspring because it will be resistant to bacteria
gene of interest
green revolution
benefits - development of new crop varieties, increased food production on the same amount of land
drawbacks - energy intensive, increased water use, gmo seeds, more pesticides and fertalizer
polyculture vs monoculture
benefits of polyculture and drawbacks of monoculture - soil regeneration, high microbial diversity, genetic diversity
benefits of monoculture and drawbacks of polyculture - high efficiency, less labor use
reasons for lack of effectiveness in Africa (green revolution)
shortage of trained plant breeders, poor yielding varieties, lack of appropriate infrastructure, expense of program
issues associated with golden rice
the rice is genetically engineered, farmers were worried that the golden rice fields would infect their fields and would be nearly impossible to stop
issues associated with flav-r-savr tomatoes
people were worried about gmos, high production costs, companies lack of experience in growing produce
rationale for developing roundup-ready and Bt crops
use of pre-harvest spraying (desiccation) - kill crops to allow uniform drying, allows earlier harvest
dangers of pesticide drift - can result in failed crop yield because of glyphosate
prevalent use of glyphosate presence in organisms and products - glyphosate is found everywhere!
global variation in use of GE crops
range of % loss of crop production due to pests/pathogens/weeds
significant (20-40%)
plant “spots”
localized areas of dead tissue on leaves, fruits, or flowers
bacterial or fungal
reduces productivity
plant “soft rots”
black and slimy
affects storage organs or fruits
non-lethal
bacterial or fungal
plant “wilts”
vessel element blocks flow of water
bacterial
caused by chewing of bugs
plant “smuts and rusts”
within family of basidiomycota, fungal mycelia that produces spores on flowers
fungal
can be considered a delacy
non lethal
plant “galls”
tumor growth induced by introduction of plasmid into plant tissue by agrobacteria
non-lethal
agrobacterium - plasmids
plant “blights”
rapidly spreading necroses that can kill plant within single growing system
lethal
fungal
danger of monoculture
degree of lethality
types of plant pests
pest insects vs beneficial insects
