As agronomists or producers, it’s our responsibility to understand how to properly manage a soybean crop for a given field’s conditions each season. Our goal should be to reduce as much stress to the soybean plant as we can, ultimately creating the right hormone balance. However, there are always situations that cause issues and for this we must continue to learn and develop on-farm trials to better understand how we should react when faced with a soybean agronomic issue.

Stress on a soybean plant requires the extra use of stored energy to minimize the impact on the plant. When a plant reallocates energy and resources, it is essentially robbing from what was going to be spent to produce leaves, flowers, pods and seeds. Once these resources are spent, the plant must restructure demand to meet current supply—this results in aborted unfertilized flowers, pods or seeds.

Once a balance has been restored and the plant is under less stress (good growing conditions resume), the soybean plant can increase the demand to utilize the current/future supply of carbon-based energy. This means creating new podding sites, or flowers, at the top of the plant, retaining more pods, and producing three beans per pod instead of one or two. This process can change many times throughout the growing season and is influenced through the balance or imbalance of plant hormones. Stress leading to yield reduction environments increases production of ABA (abscisic acid) and ethylene, which creates an imbalance with cytokinin and auxins.