Fusarium head blight (FHB) can cause contamination of cereal grain with mycotoxins. Winter wheat is also infected with FHB. It is more resistant than durum wheat to head infection and less than other small grain cereals. The aim of this study was to identify winter wheat lines that combine low head infection and kernel damage with low toxin contamination. Resistance to FHB of 27 winter wheat lines and cultivars was evaluated over a three-year experiment established in two locations. At the anthesis stage, heads were inoculated with Fusarium culmorum isolates. The FHB index was scored and the percentage of Fusarium-damaged kernels (FDKs) assessed. The grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone content. The average FHB index was 12.9%. The proportion of FDK was 6.9% (weight) and 8.5% (number). An average content of deoxynivalenol amounted to 3.543 mg/kg and nivalenol to 2.115 mg/kg. In total, it was 5.804 m/kg of type B trichothecenes. The zearalenone content in the grain was 0.214 mg/kg. Relationships between FHB index, FDK and mycotoxin contents were highly significant for wheat lines; however, they were stronger for FDK versus mycotoxins. Breeding lines combing all types of FHB resistance were found, and five of them had resistance similar to that of wheat lines with the Fhb1 gene.

The aim of the study was to determine the presence Fusarium species and mycotoxins in winter wheat grain in Poland. Grain samples from different locations in Poland in 2009 and 2010 were analysed for the content of biomass of Fusarium species and mycotoxins. In 2009 biomass of F. graminearum and F. poae was present in all samples, F. culmorum in 82% of samples, F. avenaceum in 55% of samples. F. sporotrichioides, F. tricinctum and F. equiseti were found only in individual samples. F. langsethiae was not detected. In 2010, five Fusarium species were detected with the exception of F. sporotrichioides. The highest content of biomass was found for F. graminearum followed by F. avenaceum, F. poae and F. langsethiae. The amount of F. culmorum biomass was very low. The most frequently occurring species was F. poae and F. graminearum. In 2009, deoxynivalenol was detected in all samples. In 2010, the average content of deoxynivalenol was lower than in 2009. Nivalenol was detected at very low concentration in both years. Significant correlations between content of F. graminearum biomass and deoxynivalenol concentration in grain and between content of F. poae biomass and nivalenol concentration in grain in 2009 were found. The most important finding of this study was that main Fusarium species infecting wheat kernels in Poland in both years was F. graminearum. The amount of biomass of F. graminearum was the highest in both years. It was present in the most samples. The other frequently detected species was F. poae, which in 2010 appeared in more samples than F. graminearum. However, the amount of F. poae biomass was lower. F. culmorum, species that was previously dominating as wheat pathogen in Poland, was found less frequently than F. graminearum. The amount of biomass of this species was the lowest in 2010.

Fusarium head blight (FHB) can cause contamination of cereal grain with mycotoxins. Triticale is also infected with FHB; however, it is more resistant than wheat to head infection. The aim of this study was to identify triticale lines that combine low head infection with low toxin contamination. Resistance to FHB of 15 winter triticale and three winter wheat lines was evaluated over a three-year experiment established in two locations. At the anthesis stage, heads were inoculated with Fusarium culmorum isolates. The FHB index was scored and the percentage of Fusarium-damaged kernels (FDKs) assessed. The grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone content. The average FHB index was 10.7%. The proportion of FDK was 18.1% (weight) and 21.6% (number). An average content of deoxynivalenol for wheat amounted to 7.258 mg/kg and nivalenol to 5.267 mg/kg. In total, it was 12.788 m/kg of type B trichothecenes. The zearalenone content in the grain was 0.805 mg/kg. Relationships between FHB index, FDK and mycotoxin contents were statistically significant for triticale lines; however, they were stronger for FDK versus mycotoxins. Lines combing all types of FHB resistance were found, and two of them had resistance similar to that of wheat lines with the Fhb1 gene.

Fusarium culmorum is a major pathogen of grain crops. Infected plants accumulate deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), or nivalenol (NIV), which are mycotoxins of the trichothecene B group. These toxins are also produced by F. graminearum species complex. New trichothecenes structurally similar to trichothecenes B but lacking the carbonyl group on C-8, designated NX toxins, were recently discovered in atypical isolates of F. graminearum from North America. Only these isolates and a few strains of a yet to be characterized Fusarium species from South Africa are known to produce NX-2 and other NX toxins. Here we report that among 20 F. culmorum strains isolated from maize, wheat, and oat in Europe and Asia over a period of 70 years, 18 strains produced NX-2 simultaneously with 3-ADON and DON or NIV. Rice cultures of strains producing 3-ADON accumulated NX-2 in amounts corresponding to 2-8% of 3-ADON (1.2 - 36 mg/kg). A strain producing NIV accumulated NX-2 and NIV at comparable amounts (13.6 and 10.3 mg/kg, respectively). In F. graminearum, producers of NX-2 possess a special variant of cytochrome P450 monooxygenase encoded by TRI1 that is unable to oxidize C-8. In F. culmorum, producers and nonproducers of NX-2 possess identical TRI1; the reason for the production of NX-2 is unknown. Our results indicate that production of NX-2 simultaneously with trichothecenes B is a common feature of F. culmorum.

RNA-viruses of the genera Ambivirus, Mitovirus, Sclerotimonavirus, and Partitivirus were found in a single isolate of Fusarium graminearum. The genomes of the mitovirus, sclerotimonavirus, and partitivirus were assigned to previously described viruses, whereas the ambivirus genome putatively represents a new species, named Fusarium graminearum ambivirus 1 (FgAV1). To investigate the effect of mycoviruses on the fungal phenotype, spontaneous loss of mycoviruses during meiosis and transmission of mycoviruses into a new strain by anastomosis were used to obtain isogenic F. graminearum strains with and without mycoviruses. Notable effects observed in mycovirus-harboring strains were (i) suppression of the synthesis of trichothecene mycotoxins and their precursor trichodiene, (ii) suppression of the synthesis of the defense compound aurofusarin, (iii) stimulation of the emission of 2-methyl-1-butanol and 3-methyl-1-butanol, and (iv) increased attractiveness of fungal mycelia for fungivorous collembolans. Increased attractiveness of mycovirus-infected filamentous fungi to animal predators opens new perspectives on the ecological implications of infection of fungi with viruses.