Written by Bob Fanning, former SDSU Extension Plant Pathology Field Specialist.
Fungicide seed treatments are used when planting many agricultural crops and are helpful in promoting stand establishment and seedling vigor. Seed treatments also help preserve yield potential and prevent quality losses in grain by preventing certain seed and soil-borne diseases.
There are many pathogens found in the soil which cause seedling diseases and contribute to the root/crown rot complex in wheat.
The root/crown rot complex can include one or more of the following diseases:
- Common Root Rot
- Fusarium Root Rot
- Rhizoctonia Root Rot
- Pythium Root Rot
These pathogens are always present in the soil at some level, waiting to take advantage of slow germination, slow early development, and unfavorable environment for wheat seedlings. These pathogens have similar symptoms and can cause poor overall health and vigor of the plant. These diseases often result in thin, uneven stands, spindly stalks, small spikes, empty/white heads, stunted plants, weak early growth, yellowing of foliage, and reduced yield and quality.
The primary recommendation to avoid the effects of the root/crown rot complex is a diverse crop rotation which includes one or more broadleaf crops. The proper choice of fungicide seed treatments can also help protect the young seedlings and get them off to a good start.
Loose Smut and Common Bunt (also known as stinking smut) appear in some wheat fields every year. These are two pathogens which are effectively controlled with the use of a labeled seed treatment. It is strongly believed that Loose Smut and Common Bunt could be virtually eliminated if all wheat producers used recommended seed treatments.
In general, seed treatments:
- Aid in managing the biotic stresses.
- Are effective only days to weeks (although new chemistry is promising longer periods of protection).
- Are used as the principal insurance against pests.
- Help the seed and seedlings make it to the stage when they can make their own energy (get the seed up and out of the ground).
Utilizing a fungicide seed treatment builds the foundation for a healthy plant. Healthy roots are the first step to building the yield potential you desire. Without that strong base, your yield potential is limited from the start and all other inputs become less valuable.
Seed treatment has been and continues to be a very economic and effective disease management tool in South Dakota wheat production.
To see the complete list of Seed Treatment products available, consult the new 2013 Wheat Crop Protection Guide, or check out the related publications below.
- Managing Crop Diseases with Seed Treatments: April 2012
- Seed Treatment Fungicide Options for Wheat in South Dakota: January 2011
For more information on wheat production in South Dakota, check out the following resources available for online purchase at the iGrow Marketplace!