What are the Origins of Corn?

Corn (the scientific name is Zea mays L., from the Greek word “zea” for a kind of grain and the West Indian word “mahis” for corn) is the most productive grain crop in the world. Grain yields higher than 400 bushels per acre (27 tons per hectare) have been reported. As impressive as corn’s productivity is its adaptability and variability. It is grown successfully in every continent but Antarctica, from equatorial lowlands to the Matnahuska Valley in southern Alaska to Andean highlands that are 12,000 feet (3600 meters) above sea level. How did this wonderfully productive and adaptable crop come into existence? 

Corn is native to the Americas. Until Columbus introduced corn to Europe, it was not being grown outside the Americas. How corn evolved is still a matter of controversy among scientists, but probably the most prevalent theory is that corn was domesticated from teosinte. Tripsacum also may have been an ancestor. Both teosinte and tripsacum are grasses that can be found growing wild in various parts of the Americas (Figures 1a and 1b).

 

Fig. 1a: Tripsacum dactyloides (Eastern gamma grass) (University of Nebraska-Lincoln, 2004)

Fig. 1b: Two types of teosinte (University of Nebraska-Lincoln, 2004)

To understand the remainder of this lesson and subsequent lessons in this series, knowledge of the primary parts of a corn plant and of its reproductive biology is necessary. If you are familiar with the basic anatomy and reproduction of corn, then you can skip the next section and proceed directly to “Races of Corn”.