Production Blog

Cold Stress Test

Pam Smith
By  Pam Smith , Crops Technology Editor
Connect with Pam:
While stress emergence scores can't protect seedling corn from a hard frost, they can help indicate what hybrids might emerge in cooler conditions and tolerate early season challenges. (DTN photo by Pam Smith)

DECATUR, Ill. (DTN) -- This week seems a perfect time to contemplate cold stress. DuPont Pioneer may not have ordered the January blizzards and frigid temperatures, but the information the company released this week explains what they are doing to help corn growers understand the risks of planting in cold, wet seedbeds.

The prolonged rains and cool conditions of 2013 gave us a taste of planting late and into cool soil conditions. Ironically, it was the 2012 drought year that warmed up a little too early and gave us a reminder of what a late cold snap can mean to seedling corn.

The reason to talk about this while snow is still flying is Pioneer wants growers to check stress emergence scores when selecting hybrids. These scores indicate a relative ability to emerge in cooler conditions, tolerate early-season challenges and ultimately, result in higher yields.

Purdue University agronomist Bob Nielsen reminds growers there is no industry-wide standard for cold tolerance ratings. "So one should certainly not compare ratings across seed companies," said Nielsen in email correspondence.

"Within a seed company's lineup, a cold tolerance rating is simply another hybrid characteristic to consider when selecting hybrids to grow on your farm," Nielsen said.

P[L1] D[0x0] M[300x250] OOP[F] ADUNIT[] T[]

"Stress emergence isn't just a trait for northern growers," noted Imad Saab, senior DuPont biotech business affairs manager, in their recent release. Saab has been doing stress emergence work at Pioneer for more than a decade. "This is a valuable trait for growers everywhere who are planting corn earlier or into cool, damp soils. With the rise in no-till or minimal-tillage systems, more corn is being planted into inhospitable soils."

Because corn historically is a warm-weather crop, finding strong cold tolerance in germplasm collections isn't always easy. "We're leveraging the genetic diversity of corn and cutting-edge molecular breeding tools to improve stress tolerance in hybrids," Saab said. "We identify germplasm that tolerates cold and water logging better, and we use this information to enrich our corn lineup with hybrids that excel in early-season performance." Saab said the addition of predictive lab testing capabilities has also helped build these traits into the pipeline.

"We've tackled the problem with good, old-fashioned field selection in the past," Saab said. "In recent years, we've added predictive lab testing capabilities along with molecular markers to enrich our pipeline for these traits. Using all three methods in combination gives us a high level of confidence that we're identifying and advancing the best germplasm to meet these challenges."

Growing the plant out in field settings allows Pioneer researchers to place them in areas subject to very cold springtime conditions -- including snow.

"We want to provide every grower a menu of products they can choose to meet their own local needs," Saab said. "One grower may require strong stress emergence traits. Another may emphasize other traits."

If a grower knows a hybrid has a lower stress emergence score, he or she can use other management approaches to mitigate the risks of early-season stress.

While cold-stress characteristics may not be at the very top of hybrid selection importance, Neilsen said it is definitely a consideration for those who farm in the northern Corn Belt or for fields that may be planted "on the early side."

For more information on early cold stress in corn:…

P[L2] D[728x90] M[320x50] OOP[F] ADUNIT[] T[]