The genetic diversity of 20 cabbage (Brassica oleracea var. capitata, including sub.var. alba and rubra) cultivars and landraces from the Gene bank of Crop Research Institute was estimated using amplified fragment length polymorphism (AFLP) marker technology. Two cultivars of Brassica pekinensis (syn. Brassica rapa var. pekinensis) were used as outliers in the study. Thirty AFLP primer combinations produced a total of 1084 fragments. A total of 806 fragments, 364 (45%) of them polymorphic, were found across 20 Brassica oleracea var. capitata accessions. The accessions were clustered into two main groups. Special subgroups, reflecting place of origin, were observed within these groups. Ten selective primer pairs were found to be most informative because each of these uniquely identified all of the accessions used. Furthermore, two accessions of Brassica pekinensis were clearly differentiated from the Brassica oleracea var. capitata accessions. AFLP is an efficient tool for determination of genetic diversity of cabbage gene bank accessions.

Fusarium culmorum is a phytopathogenic fungus causing Fusarium head blight (FHB), which negatively affects cereals by producing mycotoxins, such as deoxynivalenol (DON). In this work, two barley cultivars, Chevron and Pedant, with different degrees of resistance to FHB were inoculated with F. culmorum. The transcription levels of the Fusarium Tri genes and barley UDP‐glycosyltransferase genes were investigated. The amounts of pathogen, DON and the detoxification product deoxynivalenol‐3‐O‐glucoside (D3G) were monitored. The greatest amounts of pathogen were detected at 21 days postinoculation (dpi) and were much lower in cv. Chevron than in cv. Pedant. No differences in the total DON conversion to D3G were observed between the cultivars. Ubiquitin‐conjugating enzyme (UBC) was identified and then used as a reference gene to monitor transcription of the Fusarium Tri genes in infected barley. Transcription of the F. culmorum Tri5, Tri4, Tri6 and Tri10 genes differed between the two cultivars. In the susceptible cultivar (Pedant), transcription of the Tri genes gradually increased from 1 dpi. In the more resistant Chevron, transcription of the Tri genes dramatically increased after 14 dpi and reached a maximum at 21 dpi. This very high but delayed transcription of Tri genes did not, however, result in a large accumulation of the mycotoxin DON. The difference between the cultivars in the transcription of barley defence genes (HvUGT13248 [GT2] and HvUGT5876 [GT1]) for UDP‐glycosyltransferases reflects the barley samples’ levels of infection. The difference in resistance to F. culmorum infection in the two cultivars is most likely not due to differences in DON detoxification, but may be due to activity against the pathogen and delayed transcription of the pathogen's Tri genes.

The transcription activities of genes somehow associated with the mycotoxin deoxynivalenol (DON) biosynthesis, namely Fusarium Tri genes, and the barley gene coding for UDP-glycosyltransferase (HvUGT13248) on different genetic backgrounds were compared. Determining the amount of the pathogen DNA was used as a useful tool for evaluating the infestation of barley cultivars. Amounts of the pathogen DNA differed in six barley cultivars infected by F. culmorum. Transcription of HvUGT13248 was related to DON content in the samples. Low pathogenic infection and low DON content were accompanied by increased Fusarium Tri10 transcription in resistant cv. Amulet. This finding confirmed our recent results and makes us propose using this change as a possible marker of barley resistance against Fusarium.

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Pavel J., Vaculová K., Faltusová Z., Kučera L., Sedláčková I., Tvarůžek L., Ovesná J. (2015): Effect of fungicide treatment on Fusarium culmorum and Tri genes transcription in barley malt. Czech J. Food Sci., 33: 326-333.Malting barley grains are essential components in the beer production. Fusarium infection can have severe effects on malt and beer, because it may inhibit the enzymatic activity in malt and may induce the occurrence of gushing and changes in the colour and flavour of the finished beer. We examined the growth of the filamentous fungi Fusarium culmorum in artificially infected and non-infected barley malting grains during the first steps of the malting process and under the effects of fungicide pretreatment (Hutton and Prosaro 250 EC) of barley plants. Our study focused on the fungi growth in two distinct barley malting cultivars Bojos and Malz. Fusarium growth was investigated by quantitative real-time PCR using TagMan MGB probes. Furthermore, we focused on the Tri5 and Tri6 genes because they play the most important roles in trichothecene biosynthesis. Surprisingly, the higher transcription activity of the Tri genes was found in the fungicide-treated cultivar Malz as compared with untreated cultivars.