December 12, 2002

Research Looking At Ways to Treat Fusarium Head Blight in Barley

While the region’s barley producers struggle to control scab in the field, NDSU researchers are studying ways to stop its effects once grain has been harvested.

Because it is undesirable for barley for human food products to be treated with fungicides in the field, the growth of scab, Fusarium head blight, and the resulting mycotoxins are serious problems. Mycotoxins are toxic chemicals produced by mold growing in food.

"This problem begins in the field as grain develops, and progresses as barley undergoes the malting process and more mycotoxins are produced," explains Charlene Wolf-Hall, an NDSU food microbiologist. She is working with associate professor Paul Schwartz and graduate student Bala Kottapoli to evaluate different treatment methods, for their effect on Fusarium infection and germ energy. Treatments must not affect germ energy. "If the germination of barley kernels is harmed, you can’t make malt," Wolf-Hall says.

The study was aimed at physical and biological treatment methods of Fusarium infection. These treatments included microwave, steam exposures, hot water treatment and electron-beam radiation. Of these methods the microwave and steam exposures were discarded because they were too damaging to the germ energy. According to Wolf-Hall the best method is the electron-beam treatment. "High doses of radiation achieved complete reduction of Fusarium infection with a slight increase of germ energy," Wolf-Hall says.

According to Wolf-Hall the study will continue to screen different treatment methods. The effects on malting quality and surviving Fusarium will also be looked at. In addition researchers will also be determining the effects of these treatments on other microbial loads in malt.

Fusarium became widespread in the region in the early 1990's. The wet and humid weather conditions provided an environment for it to grow on small grains. If some of these mycotoxins are consumed in high amounts, severe gastrointestinal upsets are the result. "This is usually in extremely moldy foods, and that is usually not a problem in the United States," Wolf-Hall says. The effects that low doses of Fusarium mycotoxins have on humans is not known.

According to Wolf-Hall, malting barley goes through a grading process. There are strict limits on malting quality, for some malting companies if there is any measure of Fusarium mycotoxins in the barley it will be used for animal consumption not human. In theory these treatment methods could be used at the grain elevator or malting companies to treat barley in storage, and make use of otherwise good quality barley.

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Source: Charlene Wolf-Hall, (701) 231-6387, charlene.hall@ndsu.nodak.edu
Writer: Stephanie Renner, (701) 231-8371, srenner@ndsuext.nodak.edu
Editor: Tom Jirik, (701) 231-9629, tjirik@ndsuext.nodak.edu