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Starchy Staples. Taro – Colocasia esculenta. Taro – Colocasia esculenta.
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Taro – Colocasia esculenta • Taro is believed to have originated in Southeast Asia and spread west and east thousands of years ago – may have been cultivated very early by people in SE Asia – eventually reached tropical Africa and from there was brought to the West Indies and South America by slaves – today it is cultivated in the tropics where it thrives in wet, saturated soil conditions – propagated by planting corms
Taro cultivation • The corm is steamed, crushed and made into a dough, then allowed to ferment by microbes – the paste is then eaten with the fingers or rolled into small balls – this is the method for making poi – staple Hawaiian food • Corms can also be prepared like potatoes – steamed, baked, roasted, or boiled • Corm is about 25% carbohydrate (about 3% sugar), 2% protein and very little fat • Good source of calcium due to presence of calcium oxalate crystals – will cause intense burning if eaten raw so must be cooked to break down the crystals
The Green Revolution • The Green Revolution refers to the transformation of agriculture that began in 1945, largely due to the life work of Norman Borlaug. One significant factor in this revolution was the Mexican government's request to establish an agricultural research station to develop more varieties of wheat that could be used to feed the rapidly growing population of the country.
Green Revolution Advances • The main technological development of the Green Revolution was the production of novel wheat cultivars. Agronomists bred cultivars of maize, wheat, and rice that are generally referred to as HYVs or “high-yielding varieties”. HYVs have higher nitrogen-absorbing potential than other varieties. Since cereals that absorbed extra nitrogen would typically lodge, or fall over before harvest, semi-dwarfing genes were bred into their genomes. A Japanese dwarf wheat cultivar (Norin 10) wheat was instrumental in developing Green Revolution wheat cultivars. IR8, the first widely implemented HYV rice to be developed by IRRI, was also a dwarf variety.
Criticisms of Green Revolution • High yields lead to unsustainable increases in human population – like Ireland and potato • HYV grains require high fertilizer inputs and mechanized agriculture – benefits large farmers, agribusiness but not small farmers • Change in diet quality – Green Revolution favors cereal grain monocultures; traditional agriculture is polyculture with many species and high nutrient diversity
Sustainable Agriculture • Sustainable agriculture integrates three main goals: environmental stewardship, farm profitability, and prosperous farming communities. These goals have been defined by a variety of disciplines and may be looked at from the vantage point of the farmer or the consumer. Sustainable agriculture refers to agricultural production that can be maintained without harming the environment.
“The term sustainable agriculture means an integrated system of plant and animal production practices having a site-specific application that will, over the long term: • Satisfy human food and fiber needs • Enhance environmental quality and the natural resource base upon which the agricultural economy depends • Make the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls • Sustain the economic viability of farm operations • Enhance the quality of life for farmers and society as a whole.” - USDA 1990 Farm Bill (Food, Agriculture, Conservation and Trade Act (FACTA) of 1990)
CUESA’S (Center for Urban Education and Sustainable Agriculture) -Guiding Principles of Sustainable Agricultural Production • Environmentally Sound - Producers actively work to create and sustain cultivated landscapes that are complex, diverse and balanced biological systems. Producers use practices that conserve and restore resources. • Humane Animal Management - While being raised, animals are allowed to engage in the natural behaviors that are important to their well-being, and are harvested in ways that minimize stress to the animals and the environment. • Economically Viable - Producers operate within a framework of sound business planning and pursue integrated and proactive approaches to marketing and sales. • Socially Just - Producers and their employees receive fair and reasonable compensation and work in a safe and respectful environment.
Challenges to Sustainable Ag • Although air and sunlight are available everywhere on Earth, crops also depend on soil nutrients and the availability of water. When farmers grow and harvest crops, they remove some of these nutrients from the soil. • Possible sources of nitrogen that would, in principle, be available indefinitely, include: • 1. recycling crop waste and livestock or treated human manure • 2. growing legume crops and forages such as peanuts or alfalfa that form symbioses with nitrogen-fixing bacteria called rhizobia
More on Challenges • Other options include long-term crop rotations, returning to natural cycles that annually flood cultivated lands (returning lost nutrients indefinitely) such as the Flooding of the Nile, and use of crop and livestock landraces that are adapted to less than ideal conditions such as pests, drought, or lack of nutrients. Change in marketing of crops – does food have to look perfect?
How to farm sustainably? • Grow a diverse number of perennial crops in a single field, each growing most in a separate season so they don’t compete • Utilize nitrogen fixation from legumes to supply nitrogen to plants that require soil nitrogen and thus allows land to be used annually without fertilizer
Need for New Food Plants Thomas Jefferson said: “The greatest service which can be rendered to a country is to add a useful plant to its culture.”
New Food From Old Aztec threshing Amaranth – Florentine Codex – 16th Century
Amaranth Facts • The Aztecs grew amaranth - Amaranthus hypochondriacus (Family Amaranthaceae). It has many properties that make it a very desirable crop - like potatoes, it is high in lysine, so when used in combination with corn (another Aztec staple) it provides a completely balanced diet - it is a highly efficient C-4 plant, more productive than soybeans, it is very hardy, and is easily cultivated with hand tools - plants grow one to two meters tall and the fruits can be rubbed by hand to break them off the plant and gather them into a basket
More Amaranth Species A. cruentus A. caudatus
Quinoa Facts • Quinoa, Chenopodium quinoa (Family Chenopodiaceae – the goosefoots), was first grown in Peru. • Quinoa has been described as resembling a cross between spinach and sorghum because both the leaves and fruits are edible. It is an annual broad-leaved plant that grows to be 1 to 2 meters tall. The seeds are high in protein, typically 12 to 18%. The protein is also of exceptional quality for a plant source. It is high in the essential amino acids lysine and methionine; lysine is low in most cereal grains and methionine is low in most beans and peas. The seeds are also high in carbohydrate.
Star Fruit or Carambola • The carambola is believed to have originated in Sri Lanka and the Moluccas but it has been cultivated in southeast Asia and Malaysia for many centuries. • There are 2 distinct classes of carambola–the smaller, very sour type, richly flavored, with more oxalic acid; the larger, so-called "sweet" type, mild-flavored, rather bland, with less oxalic acid. • Carambola is rich in antioxidants and vitamin C and low in sugar, sodium and acid. It is also a potent source of both primary and secondary polyphenolic antioxidants
Kiwi Fruit • The kiwifruit is the edible fruit of a cultivar of the woody vine Actinidia deliciosa and hybrids between this and other species in the genus Actinidia. The fruit was developed in New Zealand. The Actinidia is native to Shaanxi China. • Kiwifruits are a rich source of Vitamin C, A and E. They also contain many flavonoid antioxidants and dietary fiber.
Pine Nuts • The edible seeds known as pinyon nuts, pine nuts and pinones (Spanish) are a wild commercial nut crop. Eaten raw roasted and in candies they were once a staple food of southwestern Indians. Pinyon ranks first among the native nut trees of the United States that are not also cultivated. Every autumn local residents, especially Navajo Indians and Spanish-Americans, harvest quantities for the local and gourmet markets.
European Pine Nuts • In Europe, pine nuts come from the Stone Pine (Pinus pinea), which has been cultivated for its nuts for over 6,000 years, and harvested from wild trees for far longer. The Swiss Pine (Pinus cembra) is also used to a very small extent.
