Soybean seed size is influenced by both genetics and the environment. Genetic effects on seed size are largely predictable but weather conditions and their effects on seed size are not. Given the atypical growing season in 2012, it is important to understand the impact on soybean seed size and shape.
In response to drought, soybean plants typically drop flowers and pods, reduce seeds per pod, abort seeds within a pod and reduce the size of the seed. The specific response depends on the soybean stage of development and severity of the drought stress. The onset of late-season rains caused seeds remaining in drought-stressed pods to swell, resulting in larger-than-normal soybean seed size.
To help growers manage larger soybean sizes, DuPont Pioneer conducted plantability tests of 2012-produced soybean seed using seven different planter metering units. In collaboration with equipment providers, Pioneer offers management tips to help growers maximize planter performance and ensure the highest possible planting accuracy with larger soybean seed.
Additional tips based on specific seed metering by planter type are available in a recent Field Facts from Pioneer.