Issue No. 21, Article 6/August 14, 2009
Bin-Run Wheat Seed from Fields Affected by Fusarium Head Blight (Scab)
This season Fusarium head blight (aka scab, caused by Fusarium graminearum) was very severe in southern Illinois wheat fields. This resulted in reduced test weights and high levels of the mycotoxin deoxynivalenol (DON, or vomitoxin), which led to big discounts and in some cases rejections of wheat at the elevator.
As tempting as it might be, it is not a good idea to use seed from these Fusarium head blight-affected fields for planting this fall. Seeds affected by Fusarium graminearum may be shrunken and discolored (white/chalky or pink). The germination rate in seed lots infected with Fusarium graminearum will be greatly reduced compared to disease-free seed lots. In addition to having Fusarium head blight, many fields also were affected by glume blotch (caused by the fungus Stagonospora nodorum) this past season, which can also reduce seed quality.
Wheat seeds infected by Fusarium graminearum, the head scab fungus (left), and non-infected seeds.
If you decide to go ahead and use bin-run seed, it is extremely important that the seed be professionally cleaned and that a fungicide seed treatment be applied. In a University of Illinois wheat fungicide seed treatment field study conducted this past season with Fusarium graminearum-infected seeds, plant emergence was increased by an average of 35% and yields were increased by 11% when seeds were treated with a fungicide.--Carl A. Bradley
Carl A. Bradley