Agriculture Flashcards
agriculture and human involvement?
- All human societies were hunter-gatherers, some still are
- Agriculture gradually began independently in several parts of the world
- Most plants are unsuitable for domestication
- Domestication imposed artificial selection on many plant traits
Dietary Fibre (what is it and what does it control? )
Types of carbohydrates that the body cannot digest
Dietary fibre helps control cholesterol, blood sugar, and regular bowl movements, but is not a significant source of energy
Secondary metabolites
Organic compounds produced by an organism that are no directly involved in growth, development, or reproduction
e.g. most parts of the potatoes contain a poisonous alkaloid: solanine
Three sisters (name and function?)
- Corn: provides a structure for climbing beans
○ Carbohydrates - Beans: fix nitrogen
○ proteins - Squash: large leaves control weeds
○ Vitamins and minerals
Active Land Management in Indigenous communities ?
- Indigenous New Guinean hunter-gatherers clear competitor trees to facilitate growth
- Keep water channels clear to access trees
- Also created grassland habitat for food plants and animals
what is Sago?
○ starch derived from the pith (spongy core) of one of several plants
Gradual Development of Agriculture?
Gathering Plants –> Agriculture
- Declines in some wild foods
- Increased availability and desirability of domesticable plants
- Increasing population density
` - Technological development
what characteristics make a crop?
- Edible
- Storage
- High yield
- Fast growing
- Annual
- Self-pollinating
main crops today ?
- Sugar cane
- Maize
- Rice
- Wheat
- Potatoes
- Soybeans
Shattering of grains refers to what?
refers to the natural process where mature seed detach from the plant and disperse
wild rice in agriculture ?
○ Shattering controlled by several genes
○ Lower yield then Einkorn wheat
○ Typically 2m or taller
Domestication in artificial selection (watermelon example)?
- Softer texture
- Netter taste
- Fewer seeds
- Bigger fruit
Industrial Revolution, when and what happened ?
(1700s-1900s)
- Steam Power
- Mechanization of textiles
- Biological understanding advances (e.g. Linnaeus, Darwin, Mendel)
- European colonialism
- Increased, then decreased use of slave and serf labor
How where potatoes introduced in Europe?
The Spanish brought potatoes to Europe, where they spread through trade, grew well in cooler, wetter regions, and were introduced to Ireland by Basque fishermen.
Potatoes in Europe – Key Points (1700s)
Distrust at first (nightshade family)
Compared to grain:
- Needs more moisture
- Yields twice the calories per hectare
- More labor-intensive
- Hard to store long-term
Population boom in N. Europe
Urban migration → Industrial Revolution
Migration to Americas
- Staple for the poor
- Small land plots could support families
Grain vs Potato Agriculture?
Grain:
- Two years planting and one year fallow
- Plowing during fallow (fallow = no growing) year kills weeds
- Dried grains stored indefinitely, can be commandeered by armies
Potatoes:
- Can be grown in “fallow” year
- Required extensive weeding during entire growing season
- Can be stored while cold overwinter
Plant diseases (types with descriptions) ?
Biotic:
causes by parasites which love on or in the host
- Mainly fungi, fungal-like organisms
- Bacteria, viruses
Abiotic:
- Chronic pollutants
- Chronic nutrient deficiencies
Why are Oomycetes (water mold) fungal like organisms?
- Filamentous growth:
- Hyphae are long filaments with multiple nuclei, sometimes divided by septa into distinct cells.
- Oomycetes are undivided. - Spore production:
- similar asexual and sexual reproduction to many fungi
- Phylogenetically they are not like fungi
Irish potato famine (cause, effected crops, impact)
Cause:
Phytophthora infestans (originated in Mexico)
Affected crops: Potatoes, tomatoes, other Solanaceae
Timeline:
1842: Outbreak near New York
1845: Famine begins in Ireland
1844 potato yield:
15,000 tons → 1847: 2,000 tons
Impact:
~1 million deaths
~1 million emigrated to North America
British response: Ignored crisis, continued meat exports
What happened after the Irish Famine?
1870:
Phytophthora infestans identified
1880s: First fungicide (Bordeaux mixture: copper sulfate + lime)
1950s: More chemical fungicides introduced
Ongoing issues:
P. infestans spreads globally
Periodic outbreaks continue
Fungicide use leads to resistant strains
2003: GM late blight-resistant potatoes developed (not commercially grown)
Controlling late Blight
Still affects potatoes and tomatoes
Prevention:
- Seed potatoes: Carefully grown, certified disease-free
Control methods:
- Fungicides (main control method)
- Sanitation (removal of infected material)
