Food production Of all crops grown, 70% are grasses. Agricultural grasses grown for their edible seeds are called cereals or grains (although the latter term, when used agriculturally, refers to both cereals and similar seeds of other plant species, such as buckwheat and legumes). Three cereals—rice, wheat, and maize (corn)—provide more than half of all calories consumed by humans. Cereals constitute the major source of carbohydrates for humans and perhaps the major source of protein; these include rice (in southern and eastern Asia), maize (in Central and South America), and wheat and barley (in Europe, northern Asia and the Americas).
food producTion of aLl cRoPs grOwn, 70% are grAsses. AgRicUltuRaL grasseS grown for thEir ediBle sEedS are CaLled cEreaLS or GRAIns (aLthoUgH thE lAtteR TerM, WhEN usEd aGRicUlTurAlly, rEfErs to boTh cEreals AnD similaR seeDs of OTher plaNT sPeCiEs, SuCh As BuckWhEAt and LegumEs). ThrEe cerEals—riCE, whEat, and mAIze (corn)—prOviDe More thAn hAlf of ALl CaloRieS COnsUmED by humAns. cErEalS cOnstiTute the maJor source of CArBohyDraTeS for humans and pErhaps THe MAjOr soURce of PrOteIn; thEse INcLUde RICe (in sOUTHern AnD EASTern asiA), mAIze (iN cEnTraL aNd SoUTH aMERica), and WhEat and bARLey (IN euRopE, northErn aSia and thE amERicas).