|Fusarium graminearum mycotoxin accumulation in wheat straw after anthesis in wheat cultivars ranging in susceptibility to Fusarium Head Blight|
K. M. BISSONNETTE (1), K. A. Ames (1), Y. Dong (2), F. L. Kolb (1), C. A. Bradley (3). (1) University of Illinois, Urbana, IL, U.S.A.; (2) University of Minnesota, St. Paul, MN, U.S.A.; (3) Univ of Illinois, Urbana, IL, U.S.A.
Mycotoxins are commonly associated with wheat grain affected by Fusarium head blight (FHB; caused by <i>Fusarium graminearum</i>), but little is known about their presence in straw. Wheat straw is used as bedding material for swine, which are sensitive to mycotoxins and may eat up to 4 kg of bedding per day. A field trial in Urbana, Illinois in 2013 and 2014 tested for the accumulation of mycotoxins in straw tissue. Twelve soft red winter wheat cultivars ranging in susceptibility to FHB were planted, and whole plants were sampled from each plot 14 days after anthesis (daa), 21 daa, and 28 daa. After harvest, stem tissue also was collected. Samples were dried, ground, and sent to the University of Minnesota for mycotoxin analysis. Three mycotoxins were tested for in this study: deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3ADON), and 15-acetyl-deoxynivalenol (15ADON). Toxin concentrations ranged from 0-39.6 ppm for DON, 0-3.8 ppm for 3ADON, and 0-16.3 ppm for 15ADON. Portions of the stem were compared at each collection date and at 28 daa, the portions significantly (<i>P</i> ≤ 0.05) differed in susceptible cultivars. Positive, significant correlation for toxin concentrations in grain and stems was observed for DON (<i>P</i> = 0.0001; <i>R</i> = 0.80), 3ADON (<i>P</i> = 0.0007; <i>R</i> = 0.34), and 15ADON (<i>P</i> = 0.0001; <i>R</i> = 0.70). Results indicate that cultivars with resistance to FHB may also have lower mycotoxin accumulation in straw tissue compared to cultivars susceptible to FHB.