As U.S. cornfields withered under drought conditions last summer, Brazil’s once-empty Cerrado region produced a bumper crop of the grain, helping feed livestock on U.S. farms and ease a drought-related spike in prices.

The U.S. imports of Brazilian corn were small by world standards. But they are rising fast, and they mark just one element of the increasingly complex and sometimes contentious relations between the world’s agricultural superpower and its fast-growing competitor amid shifts in the global economy.

Starting at zero in 2010, Brazilian corn exports to the United States are on pace to exceed $10 million this year and are bound to rise as farmers here expand planting and more corn is funneled to nonfood uses, such as ethanol production. Brazil is expected next year to dethrone the United States as the world’s largest producer of soybeans.

Just as American firms have moved production to China to be close to potential consumers, the John Deere equipment trundling across Brazilian fields and the Kellogg’s Corn Flakes found in Brazilian supermarkets come from local factories.

For more, see: In sign of growing clout, Brazil’s corn helps hold up U.S. market