Brachypodium distachyon is a useful model organism for studying interaction of cereals with phytopathogenic fungi. The present study tested the possibility of a compatible interaction of B. distachyon with the endophytic fungus Microdochium bolleyi originated from wheat roots. There was evaluated the effect of this endophytic fungus on the intensity of the attack by pathogen Fusarium culmorum in B. distachyon and wheat, and also changes in expression of genes (in B. distachyon: BdChitinase1, BdPR1-5, BdLOX3, BdPAL, BdEIN3, and BdAOS; and in wheat: TaB2H2(chitinase), TaPR1.1, TaLOX, TaPAL, TaEIN2, and TaAOS) involved in defence against pathogens. Using light microscopy and newly developed specific primers was found to be root colonization of B. distachyon by the endophyte M. bolleyi. B. distachyon plants, as well as wheat inoculated with M. bolleyi showed significantly weaker symptoms on leaves from infection by fungus F. culmorum than did plants without the endophyte. Expression of genes BdPR1-5, BdChitinase1, and BdLOX3 in B. distachyon and of TaPR1.1 and TaB2H2 in wheat was upregulated after infection with F. culmorum. M. bolleyi-mediated resistance in B. distachyon was independent of the expression of the most tested genes. Taken together, the results of the present study show that B. distachyon can be used as a model host system for endophytic fungus M. bolleyi.

A facultative parasite of cereals, Fusarium culmorum is a soil-, air- and seed-borne fungus causing foot and root rot, fusarium seedling blight, and especially Fusarium head blight, a spike disease leading to decreased yield and mycotoxin contamination of grain. In the present study, we tested changes in expression of wheat genes (B2H2, ICS, PAL, and PR2) involved in defence against diseases. We first compared expression of the analysed genes in seedlings of non-inoculated and artificially inoculated wheat (variety Bohemia). The second part of the experiment compared expression of these genes in seedlings grown under various treatment conditions. These treatments were chosen to determine the effects of prochloraz, sodium bicarbonate, ergosterol, aescin and potassium iodide on expression of the analysed defence genes. In addition to the inoculated and non-inoculated cultivar Bohemia, we additionally examined two other varieties of wheat with contrasting resistance to Fusarium sp. infection. These were the blue aleurone layer variety Scorpion that is susceptible to Fusarium sp. infection and variety V2-49-17 with yellow endosperm and partial resistance to Fusarium sp. infection. In this manner, we were able to compare potential effects of inductors upon defence gene expression among three varieties with different susceptibility to infection but also between inoculated and non-inoculated seedlings of a single variety. The lowest infection levels were detected in the sodium bicarbonate treatment. Sodium bicarbonate had not only negative influence on Fusarium growth but also positively affected expression of plant defence genes. Expression of the four marker genes shown to be important in plant defence was significantly affected by the treatments. The greatest upregulation in comparison to the water control was identified under all treatments for the B2H2 gene. Only expression of PAL under the ergosterol and prochloraz treatments were not statistically significant.

The use of biological control is becoming a common practice in plant production. One overlooked group of organisms potentially suitable for biological control are Rhizoctonia-like (Rh-like) fungi. Some of them are capable of forming endophytic associations with a large group of higher plants as well as mycorrhizal symbioses. Various benefits of endophytic associations were proved, including amelioration of devastating effects of pathogens such as Fusarium culmorum. The advantage of Rh-like endophytes over strictly biotrophic mycorrhizal organisms is the possibility of their cultivation on organic substrates, which makes their use more suitable for production. We focused on abilities of five Rh-like fungi isolated from orchid mycorrhizas, endophytic fungi Serendipita indica, Microdochium bolleyi and pathogenic Ceratobasidium cereale to inhibit the growth of pathogenic F. culmorum or Pyrenophora teres in vitro. We also analysed their suppressive effect on wheat infection by F. culmorum in a growth chamber, as well as an effect on barley under field conditions. Some of the Rh-like fungi affected the growth of plant pathogens in vitro, then the interaction with plants was tested. Beneficial effect was especially noted in the pot experiments, where wheat plants were negatively influenced by F. culmorum. Inoculation with S. indica caused higher dry shoot biomass in comparison to plants treated with fungicide. Prospective for future work are the effects of these endophytes on plant signalling pathways, factors affecting the level of colonization and surviving of infectious particles.

In recent years, recurrent droughts have significantly affected spring barley production, reducing the quantity and quality of grain. This study aims to identify genotype-specific traits and the drought resilience of six different Hordeum vulgare L. (spring barley) genotypes, while also examining the potential of potassium application and fungal endophyte Serendipita indica inoculation to mitigate the negative effects of dry periods during the growing season. Field experiments were conducted over a three-year period from 2020 to 2022, measuring physiological, growth, and yield parameters. To get insight into the physiological state of the plants, we measured the soluble sugars content and the ratio of stable carbon isotopes in the flag leaf tissue, which reflects conditions during its formation. The dominant factors that influenced the measured parameters were the genotypes and seasons, as well as their interaction, rather than other experimental factors. The results showed that the Spitfire and Accordine varieties were the best performing in both the 2020 and 2021 seasons, as indicated by their yield. However, in the drier 2022 season, the yield of these two varieties decreased significantly (to 55% for Spitfire and to 69% for Accordine of their yield in 2021), while for the arid-region genotypes, it remained at the same level as the previous year. This study sheds light on the potential of various genotypes to withstand periods of drought and the effectiveness of using potassium application and S. indica inoculation as mitigation approaches.

Eyespot is one of the most important fungal diseases of wheat in the Czech Republic. As part of a long-term study (2015–2024), the occurrence, population structure, and pathogenic variability of Oculimacula yallundae and Oculimacula acuformis were investigated. In total, 356 O. yallundae, 24 O. acuformis, and 33 mixed cultures were collected and identified using PCR. The study also included small-plot inoculation trials (2022–2023) to assess the response of widely grown winter wheat cultivars. Disease severity was evaluated visually, pathogen DNA was quantified using qPCR, and the presence of the resistance gene Pch1 was determined with the STS marker Xorw1. In addition to these analyses, monitoring of fungicide resistance to two commonly used fungicides (fluxapyroxad and prothioconazole) was performed. The results showed significant differences among cultivars and seasons. Genotypes carrying Pch1—including Annie, Campesino, Illusion, KWS Donovan, LG Absalon, and Pallas—exhibited the lowest levels of infection, whereas Mercedes and Dagmar were the most susceptible. The qPCR reliably detected and distinguished both pathogens, with O. yallundae occurring at higher concentrations. Fungicide sensitivity testing revealed EC₅₀ values (mean ± SD) of 0.09 ± 0.13 μg·mL⁻¹ for fluxapyroxad and 0.30 ± 0.22 μg·mL⁻¹ for prothioconazole, indicating that eyespot pathogens remain largely sensitive, with only minor signs of reduced sensitivity.

The pollen beetle, Brassicogethes aeneus, is a major pest of winter oilseed rape in Europe, and the development of insecticide resistance remains a key challenge for its management. This study evaluated recent changes in susceptibility of B. aeneus populations to lambda-cyhalothrin, etofenprox, acetamiprid and thiacloprid in the Czech Republic during 2020–2025. Adult beetles were collected annually from 14 agricultural localities and tested using standardized IRAC vial bioassays. Dose–response parameters (LC₅₀ and LC₉₀), relative susceptibility ratios, and mortality at recommended field doses were analyzed using weighted linear mixed-effects models. Susceptibility-related responses differed markedly among insecticides and years. Absolute LC values occupied different numerical ranges among compounds, while mortality at the recommended field dose indicated the highest efficacy for acetamiprid and thiacloprid and the lowest for lambda-cyhalothrin. Several LC- and RSR-based endpoints showed elevated values around 2021–2022, followed by lower values in later years, although the magnitude and direction of temporal changes differed among insecticides. Significant insecticide × year interactions further demonstrated compound-specific temporal trajectories. Locality contributed to variability in LC-based endpoints but explained only a limited proportion of total variance. Long-term monitoring provides valuable information for resistance management and supports the need for diversified insecticide use in oilseed rape pest control.