Influence of Simulated Wind Lodging on Corn Growth and Grain Yield

Abstract

Root lodging of entire stands of corn (Zea mays L.) often occurs when strong winds are accompanied by heavy rain and saturated soil. Root lodging is especially severe when plants are in mid-vegetative stages and have not yet developed adequate brace roots to help anchor the plants. The objective of this study was to measure the effects of wind lodging on plant recovery, growth, and grain yield. Root lodging due to wind was simulated in a field experiment by saturating the soil with irrigation water and manually pushing corn plants over at the base, perpendicular to row direction. Treatments applied were a control and simulated wind lodging at V10, V13 to V14, and V17 to Rl stages in 1985 and Vll to V12, V15, and VT stages in 1986. Three hybrids were included. The upper region of plants straightened to vertical within two days following lodging, and lodging did not affect subsequent timing of plant development. The angle between the below-ear stalk and soil surface at harvest decreased from 73 to 85° with lodging at early (V10–V12) stages to 22 to 36° at late (V17-R1) stages due to more pronounced lower stalk curvature. This resulted in ear height reductions from 52 to 57 in. for controls to less than 30 in. when lodging occurred after V17. These results indicate that mechanical harvest of corn wind lodged during V10 to Rl stages will likely be possible, but slow harvest speeds may be necessary to minimize losses. Compared to hand-harvested grain yields of control plots, grain yield decreased by 2 to 6%, 5 to 15%, and 13 to 31% when lodging occurred at early (V10–V12), medium (V13–V15), and late (V17–R1) stages, respectively. Hybrid differences in yield response to lodging appeared to be related primarily to variations in developmental stages at the time lodging treatments were applied. Further research is needed to determine the physiological factors responsible for reduced yield following wind-induced root lodging and to assess whether the yield loss percentages in this study apply under different levels of crop productivity and variable environmental conditions.