The appropriate selection of various traits in valuable plants is very important for modern plant breeding. Effective resistance to fungal diseases, such as powdery mildew, is an example of such a trait in oats. Marker-assisted selection is an important tool that reduces the time and cost of selection. The aims of the present study were the identification of dominant DArTseq markers associated with a new resistance gene, annotated as Pm11 and derived from Avena sterilis genotype CN113536, and the subsequent conversion of these markers into a PCR-based assay. Among the obtained 30,620 silicoDArT markers, 202 markers were highly associated with resistance in the analysed population. Of these, 71 were selected for potential conversion: 42 specific to resistant and 29 to susceptible individuals. Finally, 40 silicoDArT markers were suitable for primer design. From this pool, five markers, 3 for resistant and 2 for susceptible plants, were selected for product amplification in the expected groups. The developed method, based on 2 selection markers, provides certain identification of resistant and susceptible homozygotes. Also, the use of these markers allowed the determination of heterozygotes in the analysed population. Selected silicoDArT markers were also used for chromosomal localization of new resistance genes. Five out of 71 segregating silicoDArT markers for the Pm11 gene were found on the available consensus genetic map of oat. Five markers were placed on linkage groups corresponding to Mrg12 on the Avena sativa consensus map.

The structure and dynamics of changes in pathogen populations can be analysed by assessing the level of virulence and genetic diversity. The aim of the present study was to determine the diversity of Blumeria graminis f. sp. avenae populations. Diversity and virulence of B. graminis f. sp. avenae was assessed based on 80 single-spore isolates collected in different European countries such as Poland (40 isolates), Germany (10), Finland (10), Czech Republic (10) and Ireland (10) using ISSR (Inter-Simple Sequence Repeats) and SCoT (Start Codon Targeted) markers. This work demonstrated differences in virulence of B. graminis f. sp. avenae isolates sampled from different countries. Molecular analysis showed that both systems were useful for assessing genetic diversity, but ISSR markers were superior and generated more polymorphic products, as well as higher PIC and RP values. UPMGA and PCoA divided the isolates into groups corresponding with their geographical origin. In conclusion, the low level of genetic differentiation of the analysed isolates has suggested that the evolution of B. graminis f. sp. Avenae population is slow, and thus the evolutionary potential of the pathogen is low. This work paves the way for future studies on B. graminis f. sp. Avenae population structure and dynamics based on genetic variability.

High molecular weight glutenin subunits plays an important role in conditioning the end-use quality of wheat products. The aim of the study was to determine the composition of HMW glutenin subunits, occurrence frequency of theses subunits and the potential of the end—use quality in spring wheat. The analysis included 81 European cultivars of spring wheat with a potential use in the food industry. Eight gene-specific markers were used to screen for HMW-GS. The analyzed genotypes showed twenty-five different allelic combinations at the Glu-A1, Glu-B1 and Glu-D1 loci. The results showed that the most common at the Glu-A1 locus was Ax2* (58%), followed by Ax1 and Axnull (the same frequency of 21%). A high variation in allelic combinations was detected at the Glu-B1 locus. The Bx7* subunit was present in 65% cultivars, Bx7 in 25%, Bx7 or Bx7* in 7.5% and Bx6 in 2.5%. The frequency of By9 was 59%, By8—21% and Bynull—20%. A higher frequency of Dx5 + Dy10 (80%) was observed at Glu-D1 compared to Dx2 + Dy12 (16%) in the analyzed cultivars. A rare pattern of the Dx5 + Dy12 subunits was also detected (in 4% of cultivars tested). Ax2*, Bx7* + By9, Dx5 + Dy10 and Ax1, Bx7* + By9, Dx5 + Dy10, which determine good technological quality in wheat, were one of the most frequently detected allelic combinations at Glu-1. The conducted analysis showed that the tested cultivars were characterized by the potentially good and very good end-use quality of wheat products. These cultivars can be used effectively in the food industry.

The selection of specific plants with desirable traits supported by molecular markers is one of the most important tools in modern breeding programs, which lead to reduce time and cost of selection. The aim of presented study was identification of dominant markers associated with Pm4 powdery mildew resistant gene in oat. To identify dominant silicoDArT markers for Pm4 gene, F2 mapping population ‘Av1860’ × ‘Fuchs’ were analyzed using DArTseq methodology. Among obtained 46 230 silicoDArT markers, 126 markers were high correlated with resistance to powdery mildew in oat conditioned by Pm4 gene. Among selected markers, 48 sequences have been chosen for potential conversion into specific STS markers. Finally, only 20 were suitable for primer design. As a result, 5 converted markers amplified expected products in resistant bulks, 3 of them segregated according to resistance in the whole population and shoved high correlation coefficient between marker and phenotype observation. Converted markers based on PCR could be used for identification of Pm4 gene in oat. Obtained results confirm the possibility of converting silicoDArT markers into PCR-based technique, which can be used in marker assisted selection (MAS).

Identifying effective sources of disease resistance is an important aspect of an effective plant protection strategy. Wild species related to cultivars constitute a rich reservoir of resistance genes. Studies conducted in oat have shown that wild species are donors of resistance genes to crown and stem rust, powdery mildew or fusarium head blight. The aim of the present study was to prove whether A. fatua could be a source of effective resistance genes to powdery mildew. This species is widespread all over the world due to its very good adaptability and can be regarded as a potential source of resistance to fungal diseases, including powdery mildew. The conducted research has shown that A. fatua is a species with a low level of resistance to powdery mildew when compared to other wild species of the genus Avena L. A total of 251 accessions were evaluated, and only 23 were identified as resistant to the individual isolates used in the host-pathogen tests. It follows that resistance to powdery mildew is not common among wild Avena species, and its good environmental adaptation is not associated to resistance to powdery mildew.