Olericulture Hort 320 Lesson 3, Domestication, Classification
Transcript of Olericulture Hort 320 Lesson 3, Domestication, Classification
Olericulture – Hort 320
Lesson 3, Domestication, Classification
Jeremy S. Cowan WSU Spokane County Extension
222 N. Havana St.
Spokane, WA 99202
Phone: 509-477-2145 Fax: 509-477-2087
Email: [email protected]
Origin, Evolution
• Nikolai Ivanovich Vavilov
Most of the varietal wealth in our crop plants was
concentrated in eight great centers of diversity:
China, Hindustan, Central Asia, Asia Minor, the
Mediterranean region, Abyssinia, Central
America, west-central S. America
Fig. 2.1 Centers of Origin
Origin, Evolution
• Nikolai Ivanovich Vavilov
Centers of origin of species coincide with the areas
where the greatest diversity exists in the species.
Video time:
http://www.youtube.com/watch?v=WQz5lb72XbE
Origin, Evolution
• Nikolai Ivanovich Vavilov
Secondary centers of origin (centers of diversity) may
be found far removed from the primary center of origin.
These may be associated with domestication
and human movement
Centers of Origin
Determination of centers:
1. Botanical evidence
2. Archeological evidence
3. Historical evidence
4. Linguistic evidence
(Items 2-4 most likely to determine center of domestication (secondary centers of origin)
Centers of Origin
Features:
Geographical location of species
origin
Site of maximum adaptation
Site of maximum diversity
Presence of related species
Usually associated with site of
domestication
Centers of Origin
Centers of Origin
Vavilov’s Centers of Diversity (origin)
lettuce, turnip
cucumber
cantaloupe
cabbage
watermelon
manioc
potato
pumpkin, tomato
corn, bean
carrot celery lettuce
onion
pepper
beet
sweet potato
okra eggplant
Centers of Origin
Centers of Origin – Major Crops
Lettuce – Europe and Asia
Cabbage – Europe
Beet – Europe
Carrot – Europe and Asia
Onion – Asia
Potato – South America
Sweet Potato – South America
Bean – South America
Centers of Origin – Major Crops
Pea – Europe and Asia
Tomato – Central America
Pepper – Central and South
America
Cucumber – Asia and Africa
Cantaloupe – Asia
Watermelon – Africa
Squash – Central and North
America
Sweet Corn – Mexico
Edible species
20,000
Species used
for food
3,000
Species cultivated
200
Major crop
species - 25
Crop Species Domestication
Began 8-10,000 years ago
Process
Foraging and unintentional selection
Early cultivation
Domestication
Intensified and large scale production
Foraging
Impact of foraging and plant management
Selection of best food types – seed distribution
Selection of best adapted types in habitat region
Unintentional altering of habitat to promote growth of certain plants (i.e. burning)
Early Cultivation
Began as man approached food production
systematically
Started as unintentional habitat alteration to favor desired
species
Led to more intense cultivation; form depended on
geographical constraints
Early Cultivation
Vegetatively propagated plants:
Re-growth from remnants
No dormancy
Discarded propagules in refuse piles
Favored in tropical regions:
Early Cultivation
Seed propagated plants:
Collected seeds may fall, germinate
(after rain) around settlements
Eventually seed were actively stored
and systematically planted
Favored in mountainous or temperate regions:
Early Cultivation
Impact of early cultivation on crop
species
Deliberate care of preferred plants
Preferential survival of edible crop
plants
Distribution to new areas of habitat
Increased population of humans and
thus populations of crop species
Domestication
Domestication
Domestication
Video Time:
https://www.youtube.com/watch?v=6odEvT-YHxE
Domestication
Characteristics of wild species:
Edible parts small, fibrous, bitter
Numerous seeds, rapidly dispersed
Poor or non-uniform seed emergence
Often contain toxic compounds
Domestication
Changes in maize
Domestication
North American marsh elder
Domestication
Changes in plants as a result of selection:
Gigantism
- often a result of changes in PLOIDY
Where PLOIDY reflects the number of chromosomes in a
SOMATIC cell (somatic versus gametic)
Domestication
Terms of Ploidy:
Monoploid – has only a single
complement of a basic chromosome set
of the species
also referred to as the haploid state (gamete cells)
Domestication
Terms of Ploidy:
Diploid – has two complete sets of the basic
chromosome number of the species
Terms of Ploidy:
Diploid – has two complete sets of the basic chromosome number of the species
Triploid
Tetrapoid
Pentaploid
Hexaploid
Domestication
Examples of Ploidy:
Diploid – corn, onion, lettuce, tomato
Triploid – taro, watermelon (seedless)
Tetraploid – cassava, potato,
Pentaploid – sweet potato, potato
Hexaploid – yams, sweet potato
Domestication
Domestication
Changes in seed as a result of selection:
Size
Uniformity of germination
# of seeds per plant
Shattering
Dormancy
Hardness of seed coat
Domestication
Other morphological and physiological changes
resulting from selection:
Loss of survival traits
Loss of photoperiod response (potato)
Emergence of mutant types (brassica)
Absence of toxic substances (tomato)
Domestication – Bean Example
Trait Wild Domesticated
Seed dispersal Present Absent
Pod wall fibers Present Absent
Seed dormancy 70% germination 90% germination
Growth habit Indeterminate Determinate
Number of pods 43.2 7.5
Pod length 5.7 cm 9.3 cm
Seed weight (100) 3.5 g 19.5 g
Days to flower 69 46
Harvest index 0.42 0.62
Flower delay (16 hr) >60 days 0 days
Domestication – Squash
Example of selected diversity in squash
Domestication – Tomato
Example of selected diversity in tomato
Domestication – Cowpea
Example of selected diversity in cowpea
Domestication
Impact of Domestication on crop species
Selection of useful traits within crop species
Elimination of survival traits resulting in dependence on
human culture
Wider distribution and adaptation
Cultivation
Defined as controlled crop production:
Includes:
Tillage
Planting and transplanting
Weed and pest control
Harvest and sometimes storage
Bolivian crop terraces
Result of intensified cultivation
Selection for traits resulting in economic benefit to the producer – directed breeding
Ease of management
Storability
Transportability
Market specific quality traits
Cultivation
Age-old question:
“Why can’t I buy a good tomato any more?”
Is the complaint valid that produce has lost quality as we concentrate on economic production factors?
Cultivation
Cultivation
Classification
Process of lumping numerous crop
species into useful categories
Classification
Classified by:
Adaptation and hardiness
Classification
Classified by environmental adaptation:
Warm-season (very tender)
Cucumber Eggplant
Lima bean Muskmelon
Okra Pepper
Pumpkin Squash
Sweet potato Watermelon
Classification
Classified by environmental adaptation:
Warm-season (tender)
Cowpea
Sweet corn
Tomato
Snap bean
Soy bean
Classification
Classified by environmental adaptation:
Cool-season (semi-hardy)
Beet Carrot
Cauliflower Celery
Swiss chard Lettuce
Parsnip Potato
Classification
Classified by environmental adaptation:
Cool-season (hardy)
Cabbage Broccoli
Brussels sprouts Cauliflower
Onions Leeks
Pea Radish
Garlic Asparagus
Classification
Classified by:
Adaptation and hardiness
Life Cycle
Classified by life cycle:
Annual
Cucumber, tomato, spinach, sweet corn
Biennial
Beet, broccoli, carrot, onion, parsley
Perennial
Asparagus, rhubarb, sweet potato
Classification
Classification
Classified by:
Adaptation and hardiness
Life Cycle
Parts used for food
Classified by edible portion:
Root – beet, carrot, turnip
Bulb – leek, onion, garlic
Stem – asparagus, kohlrabi
Flower – cauliflower, broccoli
Tuber – potato
Classification
Classification
Classified by edible portion:
Fruit – cucumber, tomato, squash
Leaf – cabbage, lettuce, spinach
Petiole – celery
Seed – beans, pumpkin seed
Classification
Classified by:
Adaptation and hardiness
Life Cycle
Parts used for food
Taxonomic grouping
(for Monday)