Agiculture Online
July 14, 2009

In as early as 2010, corn farmers may have a big-time new tool in their crop toolbox: Drought tolerance.

Officials with Pioneer Hi-Bred International, Inc., announced this week plans to accelerate the company’s Accelerated Yield Technology (AYT) research on drought tolerance, with a goal of 2010 for bringing the product to market. The timetable is pending on-farm drought stress trials, officials say.

The new corn hybrids, known as Drought I on the Pioneer Research and Development pipeline, contain native corn drought-tolerance genes that have been identified through marker-assisted selection and advanced into elite genetics using the tools of AYT. The hybrids will be marketed in dryland and limited-irrigation growing environments of the western Corn Belt where yield expectations typically are lower due to lack of adequate rainfall and available water.

Drought I corn hybrids will be developed using native drought-tolerance traits, therefore they will not require regulatory approvals for commercialization or export, officials say.

"This is a huge step-change in a corn plant’s ability to yield with less water," says Pioneer senior research manager Jeff Schussler. "Two main factors in improving drought tolerance are a plant’s resource capture and its resource utilization. Through our multifaceted research, we have identified genes that allow the corn plant to significantly improve in both areas — the plant’s ability to capture more resources such as water, sunlight and nutrients and to allow for better utilization — in other words, improving the plant’s effectiveness in using resources."

Yield improvement targets for Drought I corn hybrids are 5% to 10% better than leader hybrids currently available in these limited-water environments, Schussler says. Hybrids with improved drought-stress tolerance also may enable farmers to expand their corn acres by planting them in more arid conditions that typically only support the production of wheat, cotton or sorghum.

"Drought is a complex trait and one that is tied directly to corn yield, which in itself has many contributing factors," Schussler says. "Our research focuses on aspects such as improving root systems or increasing the plant’s ability for silks to emerge during drought stress. We have to modify the corn plant’s natural conservative tendencies and instead, produce more grain per inch of water. Research has allowed us to strike a balance between energy for an improved root system while avoiding a potential negative impact on the development and yield above ground."