Des Moines, Iowa
May 25, 2002

Researchers at Purdue University look at whether chilling injury effects corn development

Midwest corn growers have seen unexplained corn ear deformities over the past ten years. Researchers at Purdue University, with funding from Pioneer Hi-Bred International, Inc., are going to evaluate whether or not chilling injury is creating these developmental problems.

The research will help growers better understand how corn hybrids are affected by isolated cases of environment stress. With the help of Pioneer professionals, growers also will be able to better identify the causes of deformities they may see in their fields.

"From my observations, growers who have seen deformities can usually identify single cold temperature events, extended cold periods or drastic temperature swings that occurred during the critical ear-size development period - V5 to about V12," says R.L. (Bob) Nielsen, professor of agronomy at Purdue University. "We believe these events cause chilling injury during the ear shoot development period, V5 to V12."

To evaluate whether chilling injury is causing ear development deformities, Purdue University researchers will be subjecting young corn plants to various combinations of optimum and sub-lethal temperatures in growth chamber conditions and evaluating subsequent ear shoot development. Researchers will use hybrids that have had prior developmental deformities in producers' fields.

Deformities that have been seen in the past include beer can ears, dumbbell ears, pinched ears and apparent poor pollination that results in scattered kernel sets. This research into the effects of chilling on corn ear development is one of four newly funded research projects that are part of Pioneer's Crop Management Research Awards program. Each year Pioneer awards more than $100,000 in research
funds to scientists at universities or other institutions in the United States and Canada. Each research project is focused on finding more cost-effective, technologically advanced and environmentally friendly ways to produce and manage crops.

Pioneer Hi-Bred International, Inc., a subsidiary of DuPont, is the world's leading source of customized solutions for farmers, livestock producers and grain and oilseed processors. With headquarters in Des Moines, Iowa, Pioneer provides access to advanced plant genetics, crop protection solutions and quality crop systems to customers in nearly 70 countries. During 2002, DuPont is celebrating
its 200th year of scientific achievement and innovation - providing products and services that improve the lives of people everywhere. Based in Wilmington, Del., DuPont delivers science-based solutions for markets that make a difference in people's lives in the areas of food and nutrition, health care, apparel,  home and construction, electronics and transportation.

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