2007 Brings Guaranteed Moisture to Iowa State's Sensitive Corn Plots

July 9th, 2007

AMES, Iowa - Many Iowa cornfields were challenged this spring by too much rain. But as in most years, producers soon may begin to question if there will be enough moisture to take their corn plants all the way through harvest.

Researchers at Iowa State University face the same dilemma as Iowa producers - the need for adequate rain to support germination, growth and pollination in experimental cornfields. Because of a new irrigation system, those researchers are breathing easier in 2007.

About a half-dozen maize geneticists at Iowa State have one or more experiments underway in a 20-acre field on what is known as the Curtiss Farm south of the Ames campus.

"We've had experiments on that farm for 10 years or more," said Patrick Schnable, plant genetics professor, associate director of the Plant Sciences Institute and director of the Center for Plant Genomics. "What's new this year is the irrigation. These experimental lines are not as robust as modern commercial hybrids, but have other characteristics that lend themselves to genetic investigations. So we don't want them to suffer drought stress."

An overhead irrigation system that was no longer needed on an Iowa State research farm near Nashua was relocated to the field last year. The College of Agriculture and Life Sciences paid for the equipment and installation. Grant funds from the research projects will cover the water bill.

Schnable said the value of the corn plants in this irrigated field far exceeds the value of bulk corn plants. "Many of the genetic crosses planted there can be traced back 10 to 50 generations. It takes a large investment in state and federal dollars to build these types of stocks," he said. "If we have a drought, we could lose the entire crop. That also would mean losing the investment of tax dollars for at least one year, and perhaps many years."

Severe drought isn't the only threat to these research corn plots. Schnable said a simple dry spell prior to and during pollination is a concern. "Pollination is more difficult in dry years, because it's harder to get adequate seed sets. Some corn genotypes just don't flower well in dry weather and pollination consequently is reduced," he said.

While Iowa State is known as a leader in corn genetics research, it was behind the times without an irrigated field for such research. "This is really important," Schnable said. "We're competing with all the other universities for federal research dollars. This irrigation system makes us more competitive for grant funds since we won't lose experiments because of a drought. Many land grant universities already had irrigation, and now we've caught up."

Mark Honeyman, coordinator of Iowa State's research and demonstration farms, said his staff will work with the maize researchers to determine if irrigation is needed, when irrigation is needed and how much irrigation is needed. "We'll consider soil moisture, recent rainfalls, the forecast, the researchers' planned work and the status of the crop," he said.

Schnable likens the new irrigation system to insurance. "Previously it was like we were living without health insurance. Now we not only have insurance, but we're practicing preventive medicine and making healthy lifestyle choices," he said.


Patrick Schnable, Agronomy, (515) 294-0975, schnable@iastate.edu
Mark Honeyman, Research and Demonstration Farms, (515) 294-4621, honeyman@iastate.edu
Susan Thompson, Agriculture and Life Sciences Communication Service, (515) 294-0705, sander@iastate.edu
Photos available from Susan Thompson.