Corn (Zea mays)

Poaceae family

Corn, or maize, is one of the world's three major grain crops. It is native to the New World and is diploid (2n=20), although many of its genes have been mapped and cloned and some of this work suggests corn may have once been tetraploid. Corn is a close relative of the gamagrasses (Tripsacum spp.) and teosintes (Zea luxurians, Z. mexicana, Z. perennis, Z. diploperennis). Corn is one of the world's most versatile crops in terms of its large number of economic uses, ranging from animal feed to cooking oil to ethanol. Popcorn (above, right), which has a hard endosperm, is one of modern America's favorite snack foods, was enjoyed by native Americans.

Sweetcorn, with its sugary endosperm, is perhaps the favorite summer vegetable in the US. Most of the field corn is dent corn, which has a combination of soft and flinty endosperm. It is also monoecious, meaning each plant bears separate male flowers (tassels-left below) and female flowers (silks and ears-right below). Corn, or maize as it is known outside America, is a member of the tribe MAYDEAE. It also has the highly-efficient C4 photosynthesis. Most of the corn varieties grown in the developed world today are hybrids, meaning they are grown from seed obtained by crossing two diverse, inbred parents.