Impact of imposed root lodging on corn growth and yield

Strong winds combined with heavy rains can push corn (Zea mays L.) plants over and pull roots part way out of the soil. Weather events that bring these conditions are becoming more frequent in occurrence in the midwestern United States. Yield losses due to root lodging have been related to partial loss of root activity and reduced light interception, but also may stem from affected pollination and kernel fill. A field study was conducted in Ohio from 2018 to 2020 that simulated root lodging from strong winds imposed at V10, V13-14, VT-R1, or R3 growth stages in three modern hybrids. Plants were pushed perpendicular to row direction at the specified stage following natural rain or irrigation events. Differences in hybrids were recorded in this study, but each hybrid exhibited a similar response to lodging (hybrid x lodging interaction was not evident). Yield was reduced by 5, 22, 43, and 33% compared to non-lodged control at V10, V13-14, VT-R1, and R3, respectively. Light interception in the upper canopy decreased when measured at R4 if lodged previously, and was of greater magnitude as lodging occurred later in the season. Poor pollination contributed to the large yield loss at VT-R1. In addition to reduced yield, increased vivipary and decreased kernel weights in the R3 treatments could further reduce grain quality. These yield losses from this study are greater than have been reported previously, and should be considered when assessing fields for severe wind damage in the future.