Soybean seed size is influenced by both genetics and the environment. The atypical 2012 growing season lended to having a more than usual range in seedbean size and shape, notes Jeff Daniels, DuPont Pioneer seed technology manager. That's why it's important to know the shape and size of those seeds before you head out to plant.
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, he explains. But onset of late-season rains can also cause 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, Daniels offers these management tips to help maximize planter performance and ensure the highest possible planting accuracy with larger soybean seed.
Planter lubricants: Mixing planter lubricants such as talc, graphite or a blend, specific to planter type, with soybean seed is critical.
Seed treatment: Generally, larger seed combined with treatment will require a higher level of management. Tank pressure, fan speeds and other adjustments should be made for the specific seed and treatment combination being planted. Refer to the planter operator's manual for recommendations.
Ground speed: High population settings, especially when combined with high ground speed, may provide challenges. The metering units operate faster with higher ground speeds, making it more challenging to keep seed in place as the unit rotates.
Many more tips based on specific seed metering by planter type are available online in a recent Field Facts