IE270 1st Edition Lecture 23 Outline of Last Lecture II. “History’s Harvest”III. Natural genetic mutation IV. Primitive genetic mutation V. Hunter gathererVI. Age of enlightenment Outline of Current Lecture VII. FOOD CROPSVIII.Grains and legumes are ideal partners for 2 reasonsIX. World countries food crops X. GrainsXI. Triticale, maize, soybeanXII. LegumesCurrent LectureFOOD CROPSGrasses and LegumesGrains and legumes are ideal partners for 2 reasons1) Agronomic compensation—Legumes fix nitrogen from the atmosphere through symbiosis with soil bacteria called Rhizobium. Thus, generating fertilizer and rotating or intercropping grains and legumes can help maintain soil fertility2) Dietary complementarity—legumes are rich in proteins, while grains are high in carbohydrates. Two foods complement each other in many cultures, cuisines, and providing a more balanced diet World countries food cropsChina—rice and soybeanAfrica—Sorghum/millet and cow peaNear East—wheat/ barley and lentil/peaCentral America/Mexico—corn and beanSouth America—Potato/sweet potato and ground nut These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Grains- Evolution and domestication of wheat in the fertile crescent of the Middle East, yet none is the precise ancestor of modern wheat- Grown on 12-15% of Earth’s arable land - Most important food crop for humans- Wheat is the result of hybridization between 3 different wild species to produce polyploidy plants- U.S. in #5 in world for producing wheat worldwide- Barley was domesticated in the same area as wheat, and is considered a founder crop of near East agriculture- Crops related to wheat and barley include oat and rye. Probably originated as weeds within wheat and barley Triticale, maize, soybeanTriticale—is a modern hybrid between wheat and rye. It is hardier than wheat, but doesn’t have the bread making quality.Maize—name given by native Americans to the staple grain that served as the basis of their civilization. It has long been hypothesized to have evolved from Teosinte1) DNA profiles of maize overlap those of a particular subspecies of Teosinte in the Balsas River Valley south of Central Mexico2) Genetic analysis of maize and Teosinte populations have identified 5 major genes responsible for the difference between the two plants3) Maize is notable for its exceptional variety at the DNA level - 2-5 times more variable than other grain crops- 14 times more variable than humans- High mutation rate and large population size on both teosinte and maize Soybeans—1) World’s most important legume crop 2) Biggest producers in order: U.S., Brazil, Argentina, China, and India3) Almost all 90% of the soybeans grown in the U.S. are genetically engineeredLegumesCharacteristics include: 5 pedaled flower, seeds born in pods, compounding leaves- About 35 species are grown for their seeds or pods- Few dozen species are used for forage- Second only to grains in importance to humans- Domestication of legume occurred in all the main agriculture centers of origin Traits selected for in the domestication process:1) Changes in plant structure2) Retention of seeds in the pod3) Non-dormant