Corn

The widespread cultivation of corn probably began in southern Spain in 1525.

An excerpt from the article 20 facts about corn

It had many advantages over wheat or barley - it yielded two and a half times more food energy (the chemical energy that animals derive from food to sustain metabolism) per unit of cultivated area.

In addition, corn could grow in successive years in the same field, in different climates (both dry and wet), and at different altitudes.