Seed treatments can play an important role in achieving uniform seedling emergence under certain conditions. Seed treatments can protect seeds or seedlings from early-season diseases, and fungicides are available to provide such protection. However, seed treatments should not be considered a cure-all for the selection of poor quality seed lots. Seed treatments will not increase poor germination due to excessive mechanical damage, poor storage conditions, genetic differences in variety, or other damage.
Head scab and Stagonospora glume blotch were at high levels in many fields this year, therefore growers need to limit losses due to these and other seed-borne pathogens by treating seed. In addition, be sure to use crop rotation and plant resistant or less susceptible varieties. Be especially concerned that saved seed may be contaminated. If head scab or Stagonospora was present at high levels in your wheat field do not use that grain for seed. These seed infesting fungi will contribute to poor quality seed resulting in reduced yield and lower test weight.
However, if you absolutely have to use scabby wheat for seed, cleaning, germ test, and fungicide seed treatment are absolutely necessary. Use the level of scabby kernels and test weight as your guide. You can determine the percent scabby kernels of you lot by using the visual chart found on the Field Crops Disease website. Cleaning will get rid of light, scabby material, and this will naturally increase the test weight of the lot. If you can increase a test weight to about 56 lb/bu (after cleaning) and your germ is above 80%, then you have decent quality seed. Gravity table would be your best option for cleaning. In addition to cleaning and treating, seeds should be stored under cool, dry conditions until planting to prevent mold development. Blending of scabby wheat with healthy wheat is another good option to increase the overall quality of the lot.
The systemic fungicide Dividend Extreme is effective in controlling seed-borne Stagonospora, but it is more effective against seed-borne scab at the higher rate than at the lower rate. Products containing Raxil used at the labeled rates are effective against seed-borne Stagonospora and have relatively good activity against seed-borne scab.
See the following websites and the pdf file for more on rating scabby wheat and fungicide seed treatment: