Indigenous corn offers genetic map

FARMINGTON, N.M. – A few thousand ears of fresh, colorful Indian corn may help archeologists learn more about the early history of Native American societies in the Southwest.
New Mexico State University is partnering with scientists and archeologists from Iowa and Arizona to map the physical and genetic characteristics of 155 varieties of Native American corn for the first time.
The research may shed new light on the migratory and trade patterns of tribes from thousands of years ago, said Mick O’Neill, superintendent of the university’s Agricultural Science Center.
Comparisons. “Anthropologists will compare the characteristics of corn varieties we’re now growing with corn samples discovered at archeological digs that are thousands of years old,” O’Neill said.
“By documenting the evolution of native corn varieties, archeologists can track the migratory patterns and trade routes of pre-Colombian tribes. That could provide new insight into the evolution of those societies.”
Spreading. Corn, or maize, originated in Mexico about 9,000 years ago and then spread throughout the Americas as tribes migrated to North, Central and South America, said archeologist Karen Adams.
“Archeologists need a baseline of information on modern Native American kinds of maize to better understand the maize we’ve dug up at pre-historic sites,” Adams said.
“The maize from archeological sites is often burned and has shrunk tremendously as a result, so we need to know something about the characteristics of modern maize to know more about the kinds of maize we look at from prehistoric periods.”
Southwest. Detailed reference guides exist on the characteristics of maize from most of Latin America and elsewhere in the U.S., but researchers have never documented the genetic and physical characteristics of maize from the U.S. Southwest, Adams said.
“We’re way behind on this,” she said.
“Most countries south of the border already compiled that kind of information in the 19th century.”
The data collected may also contribute to plant breeding programs, said plant biologist Candice Gardner.
“Modern researchers look for genes with unique traits,” Gardner said.
“As we analyze and document these maize varieties, we may identify genes that could be used to improve other kinds of corn.”
Attributes. Because Native American varieties evolved in harsh growing conditions, they may have useful attributes, O’Neill said.
“These varieties developed under arid conditions and in alkaline, infertile soils,” O’Neill said. “The project may help breeders develop new, drought-tolerant varieties.”
The Ames, Iowa, research station – the USDA’s repository for all North American corn varieties – provided seeds for the project.
Scientists from New Mexico State University and Iowa State University planted and cared for the corn.
They harvested a few thousand cobs in 2004 and 2005, as well as stalks, leaves, stems and other plant material.
The Iowa researchers will now analyze and document all plant characteristics and genetic information for each variety and then place the findings on the USDA’s Germplasm Resources Information Network.
For their part, Adams and other archaeologists will compare the harvested corn with cobs from archeological sites.