A root comparison study conducted this season at Monsanto’s Gothenburg Water Utilization Learning Center in Gothenburg, Neb., provided a dramatic demonstration of just how important a deep, strong root structure is to help corn plants withstand drought conditions.
The research program evaluated the performance of a Dekalb drought-tolerant corn product with a competitive drought-tolerant hybrid and a shallow-rooted product. A root dig conducted in mid-September showed that the Dekalb product had a significantly deeper, more evenly spread root structure than the other two products.
The result was healthier ears and a yield advantage for Dekalb of 12 bushels to 15 bushels per acre versus the competitors. It should be noted that there was no confirmation that either of the comparison hybrids were what would have been recommended for the region or soil type.
Michael Petersen, former soil scientist with the U.S. Department of Agriculture and current agronomist with Orthman Manufacturing, a tillage and earth-moving company, compared the Dekalb root structure to a thick, vertical carrot that extended down 85 inches. In comparison, he said the competitive hybrid roots were primarily limited to 20 to 24 inches in depth.
Petersen said because more water and more nutrients are contained from 30 to 80 inches below ground, deeper roots can help plants withstand lengthy drought stress. “We see that when we have a deeper root system, it has a chance to be able to get water from all of that soil profile compared with only taking it predominantly from the upper 20 inches,” he explained.
Mark Reiman, Gothenburg Learning Center agronomist, said all three products received minimal irrigation, requiring the plants to stretch their roots, until around Aug. 1, at which time the water was shut off and plants had to cope with hot, dry conditions.
“Deep, strong roots mean that your plants are going to be anchored to the soil very well,” he said. “They are going to have a chance of rooting down and accessing the soil moisture and using that to help farmers protect their yield in a drought year.”
This December Dekalb will introduce new products with the stewarded introduction of Genuity DroughtGard Hybrids in the Western Great Plains for 2013 planting. These products combine the Dekalb brand’s drought-tolerant genetics, developed through the brand’s industry leading breeding program, with the industry’s first drought-tolerant biotech trait and agronomic practices. The Dekalb DroughtGard Hybrids available for planting in 2013 delivered farmers more than 5 bushels per acre versus competitor products in field trails this year.