Drought-Tolerant Hybrid Response to Crop Rotation and Tillage in the Eastern Corn Belt.

Adoption of sustainability practices such as no-till production has been increasing in the Eastern Corn Belt, but diversification of crop rotations has been decreasing. Wet springs in heavy clay soils can limit early corn root development, which may lead to the increased incidence of drought stress later in the season. Rotating corn with soybeans has been shown to improve yield 5-10%, but it is unclear if drought-tolerant hybrids will experience a similar yield response compared to previously evaluated hybrids. A field study was conducted from 2013-2015 at two Ohio locations (Hoytville and South Charleston, OH) to evaluate the influence of tillage (no-till vs. conventional tillage) and crop rotation (continuous corn vs. corn-soybean rotation) on grain yield of drought-tolerant (P0210AM-R and P1352AMXT) and conventional (P0448AM1 and P1184AM1) hybrids. The study was conducted as a split-split plot randomized complete block design, with tillage as the whole-plot factor, rotation as the sub-plot factor, and hybrid type as the sub-plot factor. While no-till production delayed silking by 1-2 days, there was no effect of tillage on grain yield. The drought-tolerant hybrids produced 4% greater yield than the conventional hybrids when grown in continuous corn, and produced similar yield when rotated with soybeans at the Hoytville location. At S. Charleston, conventional hybrids produced similar yield to the drought-tolerant hybrids in the continuous corn cropping sequence, but the drought-tolerant hybrids produced 5% greater yield than the conventional hybrids when rotated with soybeans. Regardless of hybrid type, the hybrids in the corn-soybean rotation produced 5-15% greater yield than the hybrids grown in a continuous corn cropping sequence. These results suggest drought-tolerant hybrids will exhibit a similar response to tillage and crop rotation as other hybrids, but may be more tolerant of continuous corn cropping systems in heavy clay soils.