Strobilurin FungicideS increaSe
don levelS in Wheat, reduce Quality
Small adjustment to conventional fungicide practice can
reduce DON levels, increasing grain quality and profitability
Twenty years ago terms such as vomitoxin or DON were unfamiliar to The application of a strobilurin fungicide around the wheat growth stage of
wheat producers, grain elevator personnel and wheat millers. However Feekes 8.0 is intended to protect the flag leaf from foliar diseases. Scab isn’t
in 1993, widespread infestation of the mycotoxin deoxynivalenol (DON) a threat until the wheat reaches flowering, Feekes 10.51. But it can take as
occurred in grain produced in eastern North Dakota and western little as a few days for wheat plants to grow from one stage to the next.
Minnesota, resulting in significant losses. Since then, DON has hit “A grower may apply a strobilurin fungicide to manage disease of the
virtually every U.S. wheat-growing region. flag leaf when his wheat is at Feekes 8 or 9,” Myers explained. “Shortly
DON is a toxic substance produced by the fungus that causes a thereafter, his wheat could be at Feekes 10.51—critical timing for scab
disease in wheat and barley known as Fusarium head blight, or prevention. That strobilurin, though, is ineffective when it comes to scab
“scab.” Because DON could pose a health risk if consumed in high and could even increase mycotoxin levels. The grower has to decide
amounts, the Food and Drug Administration (FDA) has set guidelines if he’s ready to invest in the labor and fungicide to make another pass
for maximum DON levels allowed in wheat products for human through his field to manage scab and protect grain quality.”
consumption and livestock feed. (Figure 1). Myers further explained the answer doesn’t have to be complicated.
Millers can set their own ppm requirements as long as the resulting “If growers can resist that urge to make a strobilurin application and
product satisfies FDA guidelines. But they may pay a premium price for wait just a few days to apply a product such as Prosaro fungicide,”
grain that already meets FDA guidelines, as it will require less processing Myers said, “they get all of the foliar disease control they expect from
to achieve an end product that meets regulatory thresholds. a strobilurin fungicide—along with scab control.”
The best way for growers to manage and even reduce DON levels in Universities conducting wheat research are emphatic that strobilurin
their grain is through the application of a fungicide. But growers need to fungicides are not effective against scab, while field trials show that
remember that timing is key and not all fungicides are created equal. Prosaro® effectively controls scab and ultimately reduces DON levels
“Growers might think the best way to fight fungal disease is to apply in grain. (Figure 2).
a strobilurin chemistry at flag leaf stage,” said Randy Myers, Ph.D., Prosaro does more than help a grower manage DON levels—it also
fungicides product manager for Bayer CropScience. “But they might not increases his yield. (Figure 3). This combination of protecting the plant
realize strobilurin fungicides do not have activity against scab. In fact, from disease and helping maximize yield potential means a grower can
strobilurins applied at the wrong time can increase DON levels.” get a premium price for his grain, thus further increasing his profits.
don PartS Per Million (PPM) regulatory claSSiFication/deScriPtion
1 ppm Finished wheat products, such as flour, bran and germ that potentially may be consumed by humans.
Grains and grain byproducts destined for swine, providing that these ingredients do not exceed 20
percent of the diet.
Grains and grain byproducts destined for all other animals, providing that these ingredients do not
exceed 40% of the diet.
Grains and grain byproducts destined for ruminating beef and feedlot cattle older than 4 months and
for poultry, providing that these ingredients do not exceed 50 percent of the diet.
Figure 2 Figure 3
don level reduction With ProSaro ProSaro increaSeS yield (bu/a)
3.50 Results from 31 winter wheat 89.3
trials conducted 2008-10 in
3.57 IN and OH. Prosaro applied at Winter wheat
3.00 n=169 winter wheat trials
Feekes growth stage 10.51. 75.9 conducted 2008-10 in OH, IN,
KY, MO, MI, TN and IL.
Prosaro applied at Feekes 10.51.
1.50 76.7 n=28 spring wheat trials
conducted 2008-10 in ND, SD
Spring wheat and MN.
1.00 Prosaro applied at Feekes 10.51.
60 65 70 75 80 85 90
Untreated Prosaro 6.5 fl oz/A Prosaro 6.5 fl oz/A Untreated
Bayer CropScience LP, 2 T.W. Alexander Drive, Research Triangle Park, NC 27709. Always read and follow label instructions.
Bayer, the Bayer Cross and Prosaro are registered trademarks of Bayer. Prosaro is not registered in all states. For additional
product information call toll-free 1-866-99-BAYER (1-866-992-2937) or visit our website at www.BayerCropScience.us