Kansas State University Extension Agronomy Friday reported on research conducted over the 2012-15 growing seasons on potential yield benefits of drought-tolerant corn hybrids. They compared DT hybrids from diverse companies with a standard non-DT counterpart of similar maturity.

Do DT hybrids perform as well as their non-B counterparts? Do Bt hybrids offer some insurance against droughty conditions in dryland corn? In both instances, the answer appears to be they do.

The results were reported by Ignacio Ciampitti, crop production and cropping systems specialist; Eric Adee, agronomist-in-charge, Kansas River Valley and East Central Experiment Fields; Kraig Roozeboom, cropping systems agronomist; Alan Schlegel, agronomist-in-charge, Southwest Research-Extension Center; and Stu Duncan, northeast area crops and soils specialist, all at KSU.

In summarizing their work, the authors made several observations:

1. Performance of individual hybrids within DT and non-DT types may vary. Some non-DT hybrids can perform nearly as well as the DT hybrids even in stressful conditions, and DT hybrids have the potential to yield with non-DT hybrids when water isn’t limiting.
2. The advantage of the DT hybrids became more evident when the water stress increased to the point of leaves rolling most days.
3. From the information at hand, it is reasonable to expect a DT hybrid to serve as a type of insurance policy to sustain yield potential under water-limited environments. It also appears that there is no yield penalty associated with DT hybrids if water-limiting conditions do not occur.

They also noted, however, "... it is critical to understand that these corn genetic materials will not produce yield if the environment is subjected to terminal drought. We cannot expect them to thrive when moisture is severely limited, especially in dryland systems."

The tests also evaluated the yield response to varying plant population and irrigation levels. The research did not find any plant response to plant population between the DT and non-DT hybrids.

The findings are important first steps, the authors note, and further research is needed to fully understand factors leading to the yield differences.

Read more about their research in the April 6, 2018 K-State Extension Agronomy eUpdate and in a K-State Research and Extension publication, Drought-tolerant corn hybrids: Yield benefits (MF3338).