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The objective of this two-year study was primarily the evaluation of the free and the bound forms of phenolic acids and phenolic aldehydes (PAAs) in grains of four selected cultivars of spring durum wheat subjected to three treatment intensities (GD—Green Deal, BT—Basic and IT—Intensive). All treatments included a common basic level and different spring production levels of nitrogen fertilisation (0 kg N in the case of GD; 30 kg N in the case of BT; and 60 kg N in the case of IT). Pesticide applications included herbicides and insecticides in both the BT and IT treatments, which were supplemented by combinations of fungicide and morphoregulator in the IT treatment. The GD treatment included only basic nitrogen, herbicide protection, and the application of a biostimulator (ExelGrow). The spring durum wheat cultivars subjected to testing were cultivated under Central European conditions, specifically in the Czech Republic’s central Bohemian region. UHPLC-ESI-MS/MS was used for the detection and accurate quantification of PAAs. In parallel, 12 other nutritional and basic technological parameters of the cereal were evaluated. Nine bound and seven free forms of PAAs were quantified in the analysed cereal samples. Bound forms of PAAs were dominant, accounting for 99.4% of total PAAs. Considering single PAAs, ferulic acid was the most abundant, accounting for 87% of the total bound PAAs. Interestingly, year and treatment intensity were the key factors in the variability of both free and bound PAAs, but these factors had different effects on bound PAAs. Under low nitrogen conditions, plants responded with an increase in free PAAs in particular, as well as in three bound PAAs. Unfavourable weather conditions, combined with the presence of biotic factors (e.g., Fusarium infections), significantly influenced the increase in both PAA groups, with the exception of free p-coumaric acid. PCA analysis confirmed close relationships between PAAs within both categories (free and bound). Subsequent correlation analysis further revealed that the immunoreactive gluten component (G12) exhibited a high negative correlation with the dominant ferulic acid (r = −0.70) and sinapic acid (r = −0.68). Additionally, moderate negative correlations were observed between four bound phenolic acids and grain hardness (r = −0.48–−0.60).

The grains of three barley varieties were milled and sieved to obtain respective milling fractions with a content of beta-glucans (b-G) from 1.4 to 10.7%. The enriched fraction obtained by the extraction and precipitation contained 24.7% of b-G. The differences between the ratio of stable C carbon isotopes were established. Milling fractions with coarse particles had more beta-glucans and a more negative ratio of δ13C isotope in comparison to the respective intact barley grain. However, the enriched fraction had a less negative isotope ratio. So, it is not expected that the deviation from the stable isotope ratio of grain in milling fractions is the result of the content of b-G, but it depends on other barley grain constituents. In different parts of barley grain, there are substances with different stable isotope ratios, and by milling and sieving, they are assorted to the same milling fraction with most of the b-G. The method for determining the ratio of a stable carbon isotope in diverse barley grain fractions, applied in this investigation, is potentially opening the possibility for an additional method of screening the concentration of bioactive constituents in barley grain.

In Europe, durum wheat is traditionally grown primarily in the Mediterranean region. A question arises as to whether now, in a situation of global climate change, the conditions for durum wheat might be more favourable also in countries with temperate continental climate. Field trials at a location in the south-eastern part of the Czech Republic with a typical European continental climate were established in four harvest years (2011 – 2014). Yield, quality and deoxynivalenol content were evaluated and the impact of year and variety was studied. The best quality was achieved in 2013, when 4 of 5 varieties met all the quality requirements for durum wheat according to Commission Regulation (EU) No. 1272 / 2009. The most frequent reason for unsatisfactory quality was loss of vitreousness and low falling number. In 2012, three varieties froze, and this year was therefore excluded from evaluation. Yield varied between 7.6 t ha−1 in 2013 to 10.9 t ha−1 in 2014 and it was in a negative, statistically significant relationship with most of qualitative traits, particularly with vitreousness (r = − 0.72). The strongest correlation between qualitative traits was found between vitreousness and thousand kernel weight (r = − 0.73) and vitreousness and test weight (r = 0.70).

Hulless oats and hulless barley are highly valued for their excellent nutritional attributes and are increasingly being promoted in human nutrition. However, special attention should be paid to the risk of their contamination by Fusarium mycotoxins, as the rate of mycotoxin reduction during processing could be much lower than that for hulled cereals. In the present study, mycotoxin contamination of two cultivars, each of hulless oats and barley suitable for food purposes were studied in a 3-year field trial established in two contrasting environments. The contents of the mycotoxins regulated by law (deoxynivalenol and zearalenone) were low, and the present legal limits for their maximum content in unprocessed cereals were far from being exceeded. The mycotoxins most frequently occurring in hulless barley were enniatins (enniatin B, enniatin B1 and enniatin A1), beauvericin and nivalenol; hulless oats most frequently contained the HT-2 and T-2 toxins, beauvericin and enniatin B. The contents of enniatins and nivalenol were higher in barley than in oats. Close, positive relationships between the contents of the individual enniatins and between enniatins, beauvericin and nivalenol were observed, which implies that co-exposure could enhance the toxic potential of these mycotoxins through synergistic effects. The results highlight the need to pay more attention to the occurrence of enniatins, beauvericine and nivalenol in hulless oats and barley used for food purposes.

A representative set of barley samples collected in the Czech Republic in 2005-2010 was used to evaluate the occurrence of Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEA), the effect of agronomic factors on the level of mycotoxin contamination and the presence of four Fusarium species (F. avenaceum, F. culmorum, F. graminearum and F. poae). A significant correlation between the year and DON as well as ZEA content in barley, and significant effects of the preceding crop and variety on DON content were confirmed. The highest level of DON content was found in grain harvested in 2009, which was in correspondence with extremely frequent detection of the producer of this mycotoxin, F. graminearum, in this year. In the other years, F. poae predominated on barley.A representative set of barley samples collected in the Czech Republic in 2005-2010 was used to evaluate the occurrence of Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEA), the effect of agronomic factors on the level of mycotoxin contamination and the presence of four Fusarium species (F. avenaceum, F. culmorum, F. graminearum and F. poae). A significant correlation between the year and DON as well as ZEA content in barley, and significant effects of the preceding crop and variety on DON content were confirmed. The highest level of DON content was found in grain harvested in 2009, which was in correspondence with extremely frequent detection of the producer of this mycotoxin, F. graminearum, in this year. In the other years, F. poae predominated on barley.

Fungi of the Fusarium genus, the agent of ear rot in maize, not only causes decrease in yields but also negatively affects grain quality and, in relation to mycotoxins production, the health of humans and animals. This study focuses on determining the species range of Fusarium fungi in naturally infected stands of conventional hybrids and transgenic Bt-hybrids of maize in the Czech Republic during 2008 and 2009. Individual species of the Fusarium genus were determined on the basis of morphological characteristics and using polymerase chain reaction. Ten mycotoxigenic species were identified in hybrid maize grains: F. subglutinans (40.4%), F. graminearum (19.8%), F. verticillioides (18.2%), F. poae (9.3%), F. proliferatum (4.0%), F. avenaceum (3.8%), F. oxysporum (1.7%), F. sporotrichioides (1.3%), F. sambucinum (1.3%) and F. culmorum (0.2%). The species F. subglutinans, F. graminearum and F. verticillioides were dominant in both years. The frequency of individual Fusarium species did not significantly differ between conventional and transgenic Bt-hybrids. Differences in species representation were determined between individual years and sites. The hypothesized markedly lower infection of individual Bt-hybrids with fungi of the Fusarium genus was not statistically significant, although most Bt-hybrids did demonstrate lower infection without that being statistically significant. The average level of infection by the Fusarium genus in 2008 was 13.2% for grains of conventional hybrids and 6.6% for Bt-hybrids (50% lower). In 2009, the average infection level was 13.6% for conventional hybrids and 12.6% for Bt-hybrids (7.4% lower). The average infection level for grains of Bt-hybrids by the species F. subglutinans, F. graminearum and F. proliferatum was lower than that for grains of conventional hybrids in both years.

The prolamin (avenin) patterns of oat (Avena sativa L.) cultivars released in the Czech Republic and in the former Czechoslovak Republic were analysed by acid polyacrylamide gel electrophoresis (A-PAGE). Forty-nine oat (Avena sativa L.) accessions of domestic origin, maintained in the Czech collection of oat genetic resources, were analysed. The evaluated set contained 18 modern and 31 old cultivars. Thirty accessions showed a homogeneous prolamin pattern. The other accessions were heterogeneous with two or three different patterns, present at different percentages. Heterogeneity was present in 48% of the old cultivars, but only in 22% of the modern cultivars. Identity indexes within the heterogeneous accessions were calculated. The index values ranged from 0.09 to 0.75. Only in two heterogeneous cultivars (Dětenický Bílý, Valečovský Bílý) the identity index between their components was higher than 0.6, indicating, that their components were most likely sister lines. All analysed cultivars could be unambiguously distinguished by their prolamin pattern. The obtained prolamin patterns will be used to complete descriptor data of the genetic resources and might be useful also in oat breeding and research.

Visual evaluation of kernels damaged by Fusarium spp. pathogens is labour intensive and due to a subjective approach, it can lead to inconsistencies. Digital imaging technology combined with appropriate statistical methods can provide much faster and more accurate evaluation of the visually scabby kernels proportion. The aim of the present study was to develop a discrimination model to identify wheat kernels infected by Fusarium spp. using digital image analysis and statistical methods. Winter wheat kernels from field experiments were evaluated visually as healthy or damaged. Deoxynivalenol (DON) content was determined in individual kernels using an ELISA method. Images of individual kernels were produced using a digital camera on dark background. Colour and shape descriptors were obtained by image analysis from the area representing the kernel. Healthy and damaged kernels differed significantly in DON content and kernel weight. Various combinations of individual shape and colour descriptors were examined during the development of the model using linear discriminant analysis. In addition to basic descriptors of the RGB colour model (red, green, blue), very good classification was also obtained using hue from the HSL colour model (hue, saturation, luminance). The accuracy of classification using the developed discrimination model based on RGBH descriptors was 85 %. The shape descriptors themselves were not specific enough to distinguish individual kernels.

The RAPD method (Random Amplification of Polymorphous DNA) was used to distinguish Tapesia acufonnis and T. yallundae isolates from other pathogens of wheat stem base diseases (Fusarium avenaceum, F. culmorum, F. nivale, Rhizoctonia cerealis and R. so/ani).Isolates of the fungi originated from infected wheat plants (Triticum aestivum L.) collected at various locations in the Czech Republic. Three decameric oligonucleotide-primers were selected as producing genotype-specific RAPD products. These markers distinguish all isolates of the above taxons. The intra-species genetic variability of these species also was studied. The values of Dice's coefficients of similarity suggest that isolates of Tapesia yallundae showed a higher degree of intra-species variability than those ofT acufonnis. A high degree of intra-species variability was identified also in Fusarium avenaceum.

One of t he diseases that have become i mportant in the Czech Republ ic recently is net blotch of ba rley caused by Pyrenophora teres (Died.) Drechs., with the imperfect stale Drechslera teres. In 1 995-1997 infected leaves of both spring and winter barley were collected in various stands and climatic regions. Al most 400 isolates of the pathogen were obtained and tested for virulence using a differential set (Cl 5791. CI 2750, CI 9819, C 8755, Stcudclli, Harbin, C 29192, CI 739, Tifang. and the suscepti ble control Beate). To assess their reaction, the laboratory method for testing leaf segments on benzimidazole was used. The most stable resistant responses, compared also with previous tests from 1991-1994, were found in Cl 739 and Tifang where the frequency of viru lent isolates did not exceed I 0% of all tested ones. These genotypes should be involved in practical breeding of barley for resistance to the pathogen.

The effect of F. culmorum inoculation on the yield and quality of grain of AF Cesar and AF Lucius barley varieties was monitored. Field experiments were conducted between 2015-2017 at two locations. In grain harvested from plots grown under natural infection conditions, the deoxynivalenol content was very low. Inoculation caused a decline in germination, a certain reduction in yield and a change in some qualitative parameters (reduction in protein and fiber content, increase in starch content), but the effect of inoculation was weak and significantly influenced by the environment and the variety. The β-glucan content was not affected by inoculation. The varieties differed significantly from each other in β-glucan content (AF Cesar > AF Lucius). The deoxynivalenol content of both varieties was comparable after the inoculation while it differed under conditions of the natural infection (AF Cesar < AF Lucius).

During 1997-1998, the reaction of the collections of winter and spring wheat varieties to Tilletia caries was determined. In both years the most diseased winter varieties were Simona and Sparta, the least diseased were Samara and Ilona. High variability in the level of infection was observed in some varieties (VIada, Estica, Regina, Vega). No winter wheat variety was completely resistant. The most diseased spring wheat variety was Alexandria in both years, while Grandur showed no infection. High variability in the level of infection was observed in the special trials with cv. Ina and Contra. In trials of the efficacy of seed dressing against T. caries and T. laevis there was variability only in the controls, but not in dressed variants.