Maize—or “corn”—has a history dating back to the beginning of agriculture, and today is used for everything from livestock feed and human consumption, to the production of starch, sweeteners, corn oil, beverage and industrial alcohol, fuel ethanol, and plastics. Maize is grown on every continent save Antarctica, and is the most widely grown grain in the world. Maize is also one of the most genetically diverse crops, allowing for selection from an incredible array of grain qualities and environmental adaptations.
Maize is an excellent example of domestication—evolution in action—and researchers compare current varieties of maize with its wild ancestor, teosinte, to illustrate this principle. Maize was first domesticated from teosinte approximately 9,000-10,000 years ago. Humans selected teosinte plants with desirable traits such as making it easier to harvest and process. It took humans several thousand years of selecting various traits from its ancestors before what we now recognize as modern maize was established. Scientific studies have identified the genes responsible for these changes and how the DNA sequence has changed respectively over time. Humans continue to modify maize by creating varieties that have improved nutrition, disease resistance, and are better adapted to a wider range of climates and water availability.
Scientists at Cornell University and the USDA are sequencing the DNA of thousands of maize varieties, and applying that information to breeding a more resilient, productive, and ecologically lower-impact plant. Today, because of our understanding of maize genetics, researchers can breed varieties that are more drought-tolerant, more pest-resistant, and many other characteristics for which scientists can correlate genetic information. This type of work is integral in making agriculture more productive, sustainable, and tolerant of environmental changes.
This project is in collaboration with the Paleontological Research Institution and funded by the National Science Foundation Plant Genome Research Program, Award 1238014: “The Biology of Rare Alleles in Maize and Its Wild Relatives.”
Additional Resources: The Maize Diversity Project