Transcript Document

Ethnobotany and Domesticated Plants
Wheat
First ethnobotanical rule
of food production
• In indigenous agriculture where the crops
are consumed and not sold, there evolves
and is maintained a reasonable level of
nutritional adequacy
Second ethnobotanical rule
of food production
• In indigenous agriculture where the crops
are grown mainly or only for sale, there
develops an expanding surplus of food. The
overall objective of such agricultural
systems is to replace a pre-existing (natural)
plant community with a cultivator-made
community
It then follows that:
If the potentially unstable increase in food
production and human population is to be
maintained, it must be consistent with three aims:
1. To operate at a maximum profit (labor/yield).
2. To minimize year-to-year instability in
production.
3. To operate so as to prevent long-term degradation
of the production capacity of the agricultural
system.
Mexican Corn Varieties
Darwin on Artificial Selection
“Although man did not cause variability and cannot
even prevent it, he can select, preserve, and
accumulate the variations given to him by the
hand of nature almost in any way which he
chooses; and thus can certainly produce a great
result… Selection by man may be followed either
methodically and intentionally, or unconsciously
and unintentionally… We can further understand
how it is that domestic races of plants often
exhibit an abnormal character, as compared to
natural species, for they have been modified not
for their own benefit, but for that of man.”
Street in Cuzco, Peru with advertisement for California seeds
Plant Germ Plasm
• The first category of germ plasm includes the
native or indigenous varieties of cultivated crop
plants used elsewhere in commercial agricultural
production.
• At present many of the major crop plants have a
limited genetic base, as these have been developed
through a series of selections that emphasize yield
often at the expense of insect or disease resistance,
environmental tolerance, multiple use, etc.
Spread of Southern Corn Leaf Blight
Southern Corn Leaf Blight
Close up of Southern Corn Leaf Blight
Southern Corn Leaf Blight – damage to ear
Sweet Potato
Healthy Sweet Potatoes
– Ipomoea batatas
Sweet potatoes with black rot
Sweet potatoes with soft rot
Sweet potatoes with russet crack
Sweet potato attacked by nematodes
Sweet potato with stem rot
Healthy sweet potato
Plant Germ Plasm
• The second category of germ plasm
material includes the identification and
collection of wild relatives of the more
commonly cultivated plants.
Wild Tomato Species
Domestic
High Altitude
Another S. sisymbrifolium
Plant Germ Plasm
• The third category includes plants not yet in
the economic system and not related to
domesticated plants. These may have
properties of great value to us, but these can
be very difficult to identify.
Seed and germplasm storage
facility – Kew Seed Bank
Breadfruit
Diane Ragone Checking Breadfruit
Collection in Hawaii
Ethnobotanical Methods
William Withering
and foxglove as a
modern medicine
Basic Working Method in Ethnobotany
1) Folk knowledge of a plant’s possible benefit to
humans accumulates.
2) Indigenous people use that plant to benefit themselves
3) The folk knowledge is then related to a scientist
4) The scientist collects and identifies the plant
5) The scientist tests the plant to determine if it really is
beneficial to humans. The form of the scientific test
can vary significantly depending upon the potential
use of the plant – whether as food, fiber, a dye,
medicine, etc.
6) The scientist will attempt to determine what exactly
makes the plant beneficial - what substance or aspect
of the plant is beneficial.
7) The scientist determines the structure of the pure
substance
Rhubarb – Rheum x. cultorum
Edible stems, deadly toxic leaves
Study of the on-going process of
domestication
1. Informant interviews – especially about desired
traits, planting methods, methods of selection for
breeding or seed stock.
2. Participation observation
3. Collection of native texts
4. Field observations – grain, fruit, or vegetable
measurements; altitude, temperature, varietal
flowering and maturation rates; mapping locations
and distances to fields from farm or village; soil
and vegetative analysis of sample fields at various
stages of crop-fallow cycle.
Phytoanthropology
• Phytoanthropology examines the extent of
similarities and differences in the responses
of various human communities to their plant
neighbors, and the reasons for these human
responses.
Bo Tree – Ficus religiosa
Silk Cotton Tree – Bombax ceiba
Arrowhead –
Sagittaria sagittifolia