Upvote:3
In point of fact, corn/maize (from now on I'll just use the US term "corn") is the world's largest grain cropยน, well ahead of wheat (which is not that far ahead of rice): The European domination over the Mesoamerican cultures had little or nothing to do with food crops. Instead, it was the result of technology and disease resistance.
Diseases should be obvious. It's hard to put up an effective resistance to foreign invaders when a large fraction of your population is sick or dead. The reasons for the differing disease resistance between Europeans & Americans is discussed elsewhere: basically it has to do with the European population being repeatedly exposed to plagues - diseases originating in Africa and Asia. The European population was descended from those who survived the plagues and so had immune systems that could cope with them. The Americans had no such source of novel diseases.
(Of course the disease transfer was not entirely one-way, syphilis being the notable example of an American disease introduced to Europe. But its sexual transmission limited its spread, compared to the airborne transmission of things like measles & smallpox, which could quickly infect entire populations.)
Technology is a bit harder to understand. One factor is said to be the lack of draft/riding animals. (Though I have some trouble with this: the Incas &c had llamas, which are good pack & small draft animals. In Europe the Sami domesticated reindeer.)
Another, and IMHO more important, factor was the lack of workable tin deposits in the Americas. Without tin you're limited to what little you can do with native copper. No tin, no bronze, and no Bronze Age. Without a Bronze Age, it's difficult if not impossible to develop iron working, so no Iron Age.
ยน As pointed out in the comments, much of the corn grown is used for animal feed or biofuel feedstocks. However, that's simply a matter of taste and economics, Taste (which of course is at least partly cultural) because many humans prefer wheat and rice, and feed corn to their animals. Economics, because corn/maize produces more food calories per acre than wheat or rice. Animals tend to get fed on whatever's cheapest.
There are also different strains of corn grown for different purposes. For human use, there are sweet corn strains, eaten as a vegetable, and grain corn strains used for corn meal. For animal feed, often the whole plant is used, not just the grain-containing ears, making it even more efficient. See "silage" for info.