I think of a seed treatment as an insurance policy: It helps protect your seed investment to enable good early-season growth and to use effective active ingredients to guard against diseases and insects. These combine to keep seed going strong all season.
Early protection is key
For the last few years, Minnesota springs have been cool and wet — conditions that are ideal for fungal pathogens that cause seedling blights. If a corn or soybean seed has been in the soil for an extended period without emerging, it can be impacted by a soilborne fungal pathogen.
Corn seedlings are particularly susceptible to rhizoctonia and pythium, and soybeans to phytophthora until the early seedling phase. It’s critical to protect your soybean seedlings from planting to V2 or V3. A seed treatment can provide that protection.
Corn seed treatments
Seed treatments for corn should include:
Fungicide. A base fungicide to reduce the risk of seed decay and seedling blights.
Insecticide. An insecticide for control of wireworm, seedcorn maggot and white grub, and for suppression of black cutworm, chinch bug, corn flea beetle, seedcorn beetle and corn leaf aphid.
Other products. A yield potential product such as the micronutrient zinc or, where it makes sense, a biological mode of action and enhanced systemic fungicide such as ethaboxam for pythium control.
Soybean seed treatments
Seed treatments for soybeans should include:
Fungicide. A fungicide that controls phytophthora, pythium, fusarium and rhizoctonia, which are the four primary diseases in Minnesota soybean fields.
Insecticide. An insecticide to manage early-season insects, especially ones that injure soybeans before they reach the V2 growth stage.
Inoculant. An inoculant to generate the colonies of rhizobia that fix nitrogen. More than 50% of the nitrogen in soybeans comes from rhizobia that’s been colonized on plant roots.
Who should treat your seed?
Most corn seed comes treated, but you can tailor treatments on soybean seed. The benefit of letting your retailer apply seed treatments is that they have quality seed treaters that are highly accurate and can ensure the right amount of active ingredient is applied. Talk with your local trusted adviser about the best option for you.
Proven in the field
Data proves the value of planting treated seed. Research from the University of Wisconsin Corn Hybrid Evaluation program indicates that between 2008 and 2018, seed survival in traditional corn hybrid trials where chemical seed treatments were used averaged 91%.
WinField United Answer Plot data from 2014 to 2019 shows that soybean seeds treated with a premium fungicide seed treatment containing a high rate of mefenoxam and sedaxane increased stand count by 9,200 plants per acre.
Most farmers have done their research and purchased their seed for 2020. With seed treatments, though, it can be hard to quantify the differences between them.
Be sure to ask your agronomist questions such as: What rate should I use? What’s the mode of action? Does this treatment protect against the diseases I could potentially have in my fields? Are there any other components I should add?
Finally, seed treatments have the potential to get seeds off to a good start, but that’s only part of the ROI and yield equation. Quality in-season management finishes the race. Be sure you have both components buttoned up this season.
Evans is a technical seed agronomist with WinField United in Minnesota. Contact him at email@example.com.