Wheat - proteins gliadin and glutenin combine with starch to produce gluten. Gluten causes wheat flour to be elastic, addition of yeast causes sugar---->CO2, bubbles of CO2 cause bread to rise. Baking sets the dough, driving out the moisture and CO2. Wheat is only grain that is appropriate for producing bread. Breads such as rye still contain a substantial amount of wheat.

Major pest of wheat is black stem rust.

Rye - from Southwestern Asia - Secale cereale
Primarily a grain crop but also used as forage. Use is in decline worldwide but still important in N. and E. Europe and parts of USSR.

Can produce good crops in areas with cold winters and hot dry summers.

Consumed in form of rye (black) bread and rye crispbread or biscuits, rye whiskey in U.S. and Canada.

Origin is thought to be as a secondary crop, as a weed of wheat and barley and used as a crop later on.

Susceptible to ergot, fungus which produces hallucinogenic compounds (derivatives of lysergic acid and LSD). Can cause gangrene, St. Anthony's fire (convulsive form). Epidemics in Europe killed 1000's, one in France killed 40,000. Those affected would go to the churches and were fed bread prepared for the clergy (made from uncontaminated rye or wheat) and symptoms disappeared so Church was given credit.

Triticale - artificially produced by crossing wheat with rye with goal of producing plant with winter hardiness of rye and commercial properties of wheat.

Used as grain or forage.

Not grown very widely but modern cultivars have yields as high as best wheat cultivars and grain is nutritionally superior.

Barley - Hordeum vulgare - widely grown as cool-season crop, cannot tolerate warm-humid climates.

Used for annimal feed, brewing malts, human food.

Origin - very early crop of the Near East, dates back to 8000 B.C. in Syria, standard food for the poor.

Introduced to New World by Columbus.

U.S. & Candada only countries with significant production.

Modern trends are to improve barley for livestock nutrition.

Rice - Oryza sativa - most important plant for human food production, especially in densely populated areas of humid tropics and subtropics (China and India are major producers, USA and Thailand are major exporters).

Origins - China about 3000 B.C.

Upland rice - grown mostly in Brazil, requires large amounts of rainfall, involves clearing humid tropical rainforest, can only grow several crops on a particular plot of land.

Wet rice - grown in standing water - majority of rice grown.

Types of rice
Indica - long grain, dry when cooked
Japonica - short grain, sticky when cooked.

Modern milling techniques which separated bran and germ resulted in outbreak of beriberi (caused by vitamin B1 deficiency)

Wild Rice - Zizania aquatica - grown in Northern part of country, production is low, demand high (gourmet treat) so price is high

Texas native Zizania texana is a rare and endangered plant.

Oats - Avena sativa - currently a secondary crop

Origin - Eastern mediterranean about 1000 B.C.

Uses - livestock feed, especially for horses, mechanization of farms, hence fewer horses led to large drop in cultivation, oatmeal.

Corn - Zea mays - only major domesticated cereal from New World (exception is Amaranth)

Origins - controversal, about 7000 ybp, modern corn found 5000 ybp in Mexico.

Two hypotheses about origin:
1. directly from teosinte (Euchaena mexicana) - catastrophic sexual transmutation.
2. directly from a now extinct S.A. form and teosinte is hybrid of Tripsacum and corn. Modern corn resulted from introgression with Tripsacum.

Uses - mostly livestock consumption except in parts of Latin America, popcorn, sweet corn, corn meal, grits, tamales, corn syrup, bourbon, industrial alcohol, corn starch (baby powder). U.S. produces about 1/2 of world's total.

Corn has low nutritional value and no gluten.
Pure corn diet results in pellagra - caused by tryptophan deficiencies.

Forage grasses - large number of grasses are used as forage grasses.

Open grazing
Hay
Silage - anaerobic fermentation of undried forage done in a silo, silage can be kept for several years.

Turf grasses

Bermuda
Bluegrass
St. Augustine
Fescue
Centipede

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