Malting is a critical step in barley (Hordeum vulgare) processing, transforming grain into a key raw material for brewing and food production. However, the process is often compromised by Fusarium spp., pathogens responsible for Fusarium Head Blight, which reduces grain quality and safety. Pulsed electric field (PEF) treatment, a promising non-thermal technology, has been studied for its potential to inactivate microbial pathogens and mitigate infection-related stress. In this study, we investigated transcriptional responses in barley infected with Fusarium spp. during malting, both with and without PEF treatment. RNA sequencing identified over 12,000 differentially expressed genes (DEGs) across four malting stages, with the third stage (24 h of germination) showing the highest transcriptional activity. DEGs were significantly enriched in pathways related to oxidative stress management and abscisic acid signaling, underscoring their importance in stress adaptation. Barley treated with PEF exhibited fewer DEGs in later malting stages compared to untreated samples, suggesting that PEF alleviates stress induced by both Fusarium infection and the malting process. Enrichment analysis further revealed that PEF treatment up-regulated stress-related pathways while down-regulating genes associated with photosynthesis and cell wall biogenesis. These findings provide novel insights into barley stress responses during malting and highlight the potential of PEF as a tool for enhancing malt quality under stress conditions.

• Klíčová slova
• Fusarium infection, Hordeum vulgare, gene expression, malting, pulsed electric field, stress response, transcriptomics,
• Publikační typ
• časopisecké články MeSH

Plant survival in temperate zones requires efficient cold acclimation, which is strongly affected by light and temperature signal crosstalk, which converge in modulation of hormonal responses. Cold under low light conditions affected Arabidopsis responses predominantly in apices, possibly because energy supplies were too limited for requirements of these meristematic tissues, despite a relatively high steady-state quantum yield. Comparing cold responses at optimal light intensity and low light, we found activation of similar defence mechanisms-apart from CBF1-3 and CRF3-4 pathways, also transient stimulation of cytokinin type-A response regulators, accompanied by fast transient increase of trans-zeatin in roots. Upregulated expression of components of strigolactone (and karrikin) signalling pathway indicated involvement of these phytohormones in cold responses. Impaired response of phyA, phyB, cry1 and cry2 mutants reflected participation of these photoreceptors in acquiring freezing tolerance (especially cryptochrome CRY1 at optimal light intensity and phytochrome PHYA at low light). Efficient cold acclimation at optimal light was associated with upregulation of trans-zeatin in leaves and roots, while at low light, cytokinin (except cis-zeatin) content remained diminished. Cold stresses induced elevation of jasmonic acid and salicylic acid (in roots). Low light at optimal conditions resulted in strong suppression of cytokinins, jasmonic and salicylic acid.

• Klíčová slova
• auxin, combined stress, cryptochrome, cytokinin, gene expression, gibberellin, phytochrome, plant hormones,
• MeSH
• aklimatizace * MeSH
• Arabidopsis * genetika   metabolismus   MeSH
• proteiny huseníčku * biosyntéza   genetika   MeSH
• regulace genové exprese u rostlin * MeSH
• světlo * MeSH
• zmrazování * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny huseníčku * MeSH

BACKGROUND: The wild relatives of crop species represent a potentially valuable source of novel genetic variation, particularly in the context of improving the crop's level of tolerance to abiotic stress. The mechanistic basis of these tolerances remains largely unexplored. Here, the focus was to characterize the transcriptomic response of the nodes (meristematic tissue) of couch grass (a relative of barley) to dehydration stress, and to compare it to that of the barley crown formed by both a drought tolerant and a drought sensitive barley cultivar. RESULTS: Many of the genes up-regulated in the nodes by the stress were homologs of genes known to be mediated by abscisic acid during the response to drought, or were linked to either development or lipid metabolism. Transporters also featured prominently, as did genes acting on root architecture. The resilience of the couch grass node arise from both their capacity to develop an altered, more effective root architecture, but also from their formation of a lipid barrier on their outer surface and their ability to modify both their lipid metabolism and transporter activity when challenged by dehydration stress. CONCLUSIONS: Our analysis revealed the nature of dehydration stress response in couch grass. We suggested the tolerance is associated with lipid metabolism, the induction of transporters and the re-programming of development coordinated by ABA. We also proved the applicability of barley microarray for couch grass stress-response analysis.

• Klíčová slova
• Barley, Couch grass, Crown, Dehydration stress, Drought, Microarray, Rhizome,
• MeSH
• elektrolyty metabolismus   MeSH
• fyziologický stres genetika   MeSH
• kyselina abscisová metabolismus   MeSH
• lipnicovité genetika   metabolismus   fyziologie   MeSH
• membránové transportní proteiny genetika   MeSH
• metabolismus lipidů genetika   MeSH
• období sucha * MeSH
• stanovení celkové genové exprese MeSH
• voda metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• elektrolyty MeSH
• kyselina abscisová MeSH
• membránové transportní proteiny MeSH
• voda MeSH

Response to a high salinity treatment of 300 mM NaCl was studied in a cultivated barley Hordeum vulgare Syrian cultivar Tadmor and in a halophytic wild barley H. marinum. Differential salinity tolerance of H. marinum and H. vulgare is underlied by qualitative and quantitative differences in proteins involved in a variety of biological processes. The major aim was to identify proteins underlying differential salinity tolerance between the two barley species. Analyses of plant water content, osmotic potential and accumulation of proline and dehydrin proteins under high salinity revealed a relatively higher water saturation deficit in H. marinum than in H. vulgare while H. vulgare had lower osmotic potential corresponding with high levels of proline and dehydrins. Analysis of proteins soluble upon boiling isolated from control and salt-treated crown tissues revealed similarities as well as differences between H. marinum and H. vulgare. The similar salinity responses of both barley species lie in enhanced levels of stress-protective proteins such as defense-related proteins from late-embryogenesis abundant family, several chaperones from heat shock protein family, and others such as GrpE. However, there have also been found significant differences between H. marinum and H. vulgare salinity response indicating an active stress acclimation in H. marinum while stress damage in H. vulgare. An active acclimation to high salinity in H. marinum is underlined by enhanced levels of several stress-responsive transcription factors from basic leucine zipper and nascent polypeptide-associated complex families. In salt-treated H. marinum, enhanced levels of proteins involved in energy metabolism such as glycolysis, ATP metabolism, and photosynthesis-related proteins indicate an active acclimation to enhanced energy requirements during an establishment of novel plant homeostasis. In contrast, changes at proteome level in salt-treated H. vulgare indicate plant tissue damage as revealed by enhanced levels of proteins involved in proteasome-dependent protein degradation and proteins related to apoptosis. The results of proteomic analysis clearly indicate differential responses to high salinity and provide more profound insight into biological mechanisms underlying salinity response between two barley species with contrasting salinity tolerance.

• Klíčová slova
• Hordeum marinum, Hordeum vulgare, glycophyte, halophyte, proteome, salinity, stress acclimation, stress damage,
• Publikační typ
• časopisecké články MeSH

Barley cultivar Amulet was used to study the quantitative proteome changes through different drought conditions utilizing two-dimensional difference gel electrophoresis (2D-DIGE). Plants were cultivated for 10 days under different drought conditions. To obtain control and differentially drought-treated plants, the soil water content was kept at 65, 35, and 30% of soil water capacity (SWC), respectively. Osmotic potential, water saturation deficit, (13)C discrimination, and dehydrin accumulation were monitored during sampling of the crowns for proteome analysis. Analysis of the 2D-DIGE gels revealed 105 differentially abundant spots; most were differentially abundant between the controls and drought-treated plants, and 25 spots displayed changes between both drought conditions. Seventy-six protein spots were successfully identified by tandem mass spectrometry. The most frequent functional categories of the identified proteins can be put into the groups of: stress-associated proteins, amino acid metabolism, carbohydrate metabolism, as well as DNA and RNA regulation and processing. Their possible role in the response of barley to drought stress is discussed. Our study has shown that under drought conditions barley cv. Amulet decreased its growth and developmental rates, displayed a shift from aerobic to anaerobic metabolism, and exhibited increased levels of several protective proteins. Comparison of the two drought treatments revealed plant acclimation to milder drought (35% SWC); but plant damage under more severe drought treatment (30% SWC). The results obtained revealed that cv. Amulet is sensitive to drought stress. Additionally, four spots revealing a continuous and significant increase with decreasing SWC (UDP-glucose 6-dehydrogenase, glutathione peroxidase, and two non-identified) could be good candidates for testing of their protein phenotyping capacity together with proteins that were significantly distinguished in both drought treatments.

• Klíčová slova
• Hordeum vulgare, crown, drought, phenotyping candidate, proteomics,
• Publikační typ
• časopisecké články MeSH