Prevalence of Fusarium fungi and Deoxynivalenol Levels in Winter Wheat Grain in Different Climatic Regions of Poland

Fusarium head blight (FHB) caused by fungi of the genus Fusarium is one of the most dangerous crop diseases, which has a wide geographic distribution and causes severe economic losses in the production of major cereal species. The infection leads to the accumulation of mycotoxins in grains, which compromises its suitability for human and animal consumption. The study demonstrated that grain samples from warmer regions of Poland, including Sulejów and Tomaszów Bolesławicki (results differed across years of the study), were colonized mainly by F. graminearum and were most highly contaminated with deoxynivalenol (DON). Samples from Northeastern Poland, i.e., Ruska Wieś, which is located in a cooler region, were characterized by a predominance of Fusarium species typical of the cold climate, i.e., Fusarium poae and Penicillium verrucosum. A Spearman's rank correlation analysis revealed that the severity of grain infection with F. avenaceum/F. tricinctum was affected by the mean daily temperature and high humidity in May, and the corresponding values of the correlation coefficient were determined at R = 0.54 and R = 0.50. Competitive interactions were observed between the F. avenaceum/F. tricinctum genotype and DON-producing F. culmorum and F. graminearum, because the severity of grain infections caused by these pathogens was bound by a negative correlation.