Search Results (122)

Numerous scientific studies have confirmed the effectiveness of seed bioactivation using electromagnetic fields (EMFs) in agriculture. This article presents the results of the remote application of an EMF TOR device in the cultivation of barley Hordeum vulgare L. Laboratory studies and field tests were conducted, showing a positive effect on the growth and development of plants both when treating dry seeds before sowing and when treating sown seeds in the field. The optimal time period for EMF treatment was determined: treating air-dried seeds with EMFs before sowing for 10–15 min increased germination by 5–18% and the growth rate of seedlings by 2–3 times. The maximum observed effect occurred during the treatment period from 7:00 to 11:00. As a result of changing the balance of phytohormones, the further stimulation of the root system and the assimilation surface of plants was noted due to a 1.5-fold increase in the content of auxins. The density of productive stems, ear length, seed set, and 1000 seed weight increased, which ultimately led to an increase in yield by more than 10% and, in some varieties, to a decrease in the protein content in grains compared to the control variant (by 3–22%), bringing them closer to brewing conditions. Full article

Selenium (Se), as a vital trace element, plays an important role in regulating the antioxidant systems of plants, strengthening photosynthetic capacity, and enhancing their stress resistance. Selenate and selenite are the dominant forms of Se available to plants in soils. This research takes highland barley as the research object, aiming to assess the impacts of plant growth, organic acid metabolite, and six transcription factor families in highland barley seedlings under varying concentrations of Na₂SeO₃. The study indicated that compared to the control group (CK), the plant height of highland barley seedlings under Se1 (0.02 g/kg Na₂SeO₃) treatment significantly increased by 66%. Under the Se2 (0.2 g/kg Na₂SeO₃) treatment, plant height significantly decreased by 28%. With Na₂SeO₃ concentration increased, the pigment content, O₂⁻ production rate, and soluble protein content in highland barley seedlings decreased, while the contents of soluble sugar, MDA, and H₂O₂ increased. Se1 treatment was found to be more beneficial for the growth and development of seedlings. The organic selenium in leaves and roots under Se2 treatment significantly increased by 1105-fold and 188-fold, respectively. The most effective migration capability from soil to leaf under Se1 or Se2 treatment was up to 6.15 or 6.56, respectively. Based on metabolomics, 30 differential metabolites of organic acids were screened from highland barley seedlings under Na₂SeO₃ treatment and showed positive correlationships with organic selenium, inorganic selenium, and total selenium in highland barley seedling leaves. Through transcriptome analysis, heatmap analysis on six major categories of transcription factors (bHLH, MYB, NAC, WRKY, GATA, and HSF) was performed. Under Se2 treatment, approximately two-thirds of the transcription factors showed high expressions. We further screened 26 differentially expressed genes (DEGs) related to Na₂SeO₃ concentration. Based on correlation analysis, there were six genes in the bHLH family, five in MYB, three in NAC, five in WRKY, and three in the GATA and HSF families that showed positive correlations with 30 differential organic acid metabolites. These results enhance our understanding of the relationship between the organic acid metabolites and transcription factor expression in highland barley seedlings under Na₂SeO₃ treatment. Full article

While pipecolic acid (Pip) mediates morpho-physiological and molecular responses during biotic stress, its roles under drought remain an inexpressible mystery. The investigation aimed to elucidate the roles of a 30μM Pip pretreatment in alleviating drought injury on barley (Hordeum vulgare L. cv, Bülbül89) seedlings. Pip pretreatment under normal or drought conditions lowered the osmotic potential (Ψs) and water saturation deficit (WSD), while optimizing the relative water content (RWC), triggered osmotically energetic molecules (OEM) and salicylic acid (SA) accumulation, improving osmotic adjustment (OA), and boosting water retention and uptake capacity (WTC, and WUC), alongwith a considerable improvement in seedling growth over non-treated plants under such conditions. Additionally, Pip pretreatment improved chlorophyll (Chl), the chlorophyll stability index (CSI), pheophytin_a, chlorophyllide_a (chlide_a), chlorophyllide_b (chlide_b), chl_a/chlide_a, chl_b/chlide_b, protoporphyrin, Mg-protoporphyrin, protochlorophyllide, and photosynthetic performance over non-treated plants under such conditions. Pip pretreatment preserves redox homeostasis in drought-stressed plants by accumulating antioxidant solutes alongside the activation of superoxide dismutase and glutathione reductase over non-treated plants. Drought distinctly reduced Ψs (more negative), RWC, photosynthetic pigment, CSI, chlorophyll assimilation intermediate, and photosynthetic performance, with an increment in chlorophyll degradation intermediate and nonenzymatic antioxidant solutes. Drought maintains OA capacity via a hyper-accumulation of OEM and SA, which results in higher WSD, WTC, and WUC. Drought triggered an oxidative burst, which was associated with a decline in the membrane stability index. These findings highlight Pip’s capability for lessening drought stress-induced restriction in barley seedlings via bolstering oxidative homeostasis, OA capacity, and stabilizing chlorophyll biosynthesis. Future research must elucidate the precise molecular mechanisms underlying Pip’s action in alleviating drought injury. Full article

Fusarium graminearum is one of the most important pathogenic fungi with a wide range of plant and animal hosts. This study investigated the effects of F. graminearum infection on the rhizosphere microbiota and growth of two barley (Hordeum vulgare L.) cultivars, Baudin and Kenpi 7, and explored microbiota transplantation as a strategy to enhance disease resistance. By exchanging surface microbiotas between varieties and analyzing rhizosphere bacterial communities using 16S rRNA sequencing, researchers observed that F. graminearum infection increased bacterial diversity and abundance, especially in Baudin barley. Growth indicators (root length, plant height, fresh/dry mass) also exhibited that Baudin barley showed stronger resistance. Functional analysis underscored that the microbial community composition of Baudin barley promoted metabolic pathways related to plant resilience and was associated with improved seedling health. In contrast, Kenpi 7 barley showed weaker resistance, emphasizing the role of seed-specific microbiotas in pathogen defense. An effective antagonistic strain, Bacillus amyloliquefaciens B1, was isolated from Baudin barley, and its inhibition rate against F. graminearum was 80%. The results showed that microbiota transplantation enhanced the disease resistance of low-diversity seeds, and identified B. amyloliquefaciens B1 as a promising biocontrol agent, providing a potential application for sustainable agriculture and reducing dependence on chemical fungicides. This study highlights the importance of seed-associated microbial communities in plant–pathogen interactions and provides a basis for the development of microbiota-based strategies to mitigate crop diseases. Full article

Aluminum toxicity in acidic soils represents a significant environmental stressor that affects yields worldwide and is only expected to worsen. Breeding resistant varieties remains the most viable solution; however, fast and robust procedures to determine cultivar viability must be developed and applied to promising genotypes. This study explored historical and modern Lithuanian-bred barley cultivars using morphometrical and biochemical markers for Al resistance and sequence and expression analyses of potential candidate genes. Morphometric seedling measurements (relative root length reduction −13.65 ± 0.33% (p < 0.001) and root tolerance index 0.86 ± 0.44 after 72 h at 8 mM Al stress) revealed the modern cv. ‘Ema DS’ to be the most Al resistant, while biochemical assays offered a poor distinction between the Al-resistant and sensitive cultivars. Thus, we determined that morphometric parameters were more effective in the early screening for barley Al resistance. The genetic screening of well-established Al resistance markers in the barley citrate transporter HvAACT1 revealed a mismatch between the observed barley phenotypes and genotypes. Further testing was conducted through expression analyses of HvAACT1 and seven aquaporin family genes, which revealed a correlation between the best empirical performance in cv. ‘Ema DS’ and a high HvAACT1 (2.02 fold change, p < 0.05) expression, despite the lack of established genetic markers, as well as a stress-induced significant upregulation of aquaporin TIP4;1 (2.45 fold change, p < 0.05), suggesting previously undiscovered regulatory mechanisms of external and internal detoxification influencing Al resistance in Lithuanian barley cultivars, as well as potential future candidates for Al-resistant barley breeding programs. Full article

Powdery mildew, caused by Blumeria graminis f. sp. hordei (Bgh), severely impacts global barley Hordeum vulgare L. (Hv) production. This investigation evaluated Egyptian barley genotypes to identify novel resistance sources and molecular markers for breeding programs. Phenotypic assessments at the seedling (growth stage, GS 32) and adult plant (GS 55–59) stages under controlled and field conditions, combined with SSR marker analysis, revealed distinct resistance profiles. Genotypes Giza 123, Giza 125, and G8 exhibited strong resistance, with Giza 123 displaying Mlo-mediated immunity. Susceptible genotypes (Giza 126, G1, G2, and G4) showed rapid disease progression (IT4; up to 80% severity). Intermediate genotypes (G5, G6, and G9) suggested quantitative resistance. Simple sequence repeat (SSR) analysis linked the EBmac0603 primer 160 bp allele to resistance and the 149 bp allele to susceptibility. The EBmac0603 primer 185 bp allele correlated with partial resistance, highlighting its utility in marker-assisted selection (MAS). The integration of phenotypic and molecular data identified Giza 123 and G8 as prime candidates for breeding, emphasizing the need for strategies like gene pyramiding or quantitative resistance incorporation in susceptible lines. This study underscores the value of Egypt’s barley diversity in advancing durable disease resistance through targeted breeding and molecular tools. Full article

With global climate change ongoing, the frequency and intensity of extreme weather events have increased annually. Hulless barley (Hordeum vulgare L. var. nudum), a primary crop cultivated in the Qinghai–Tibet Plateau mountains, frequently encounters multiple abiotic stresses including low temperature, high salinity, and drought. Among these stresses, drought has emerged as a critical environmental constraint affecting sustainable agricultural development worldwide. Establishing a drought resistance evaluation system for the hulless barley germplasm during its seedling stages could provide a theoretical foundation for screening and breeding drought-tolerant cultivars to address climate change challenges. This study employed two drought-sensitive (YC85 and YC88) and two drought-tolerant (ZY1252 and ZY1100) cultivars to develop an effective drought resistance evaluation protocol for hulless barley. Our findings identified several reliable indicators for assessing drought tolerance at the seedling stage: fresh mass, chlorophyll fluorescence parameters (F_v/F_m, NPQ, and R_FD), photosynthetic parameters (E and gsw), and reactive oxygen species (ROS) levels. The established evaluation system was subsequently applied to three uncharacterized cultivars (ZY673, ZY1403, and KL14). The results classified all three as drought-sensitive, with ZY1403 exhibiting the highest sensitivity. Our work has established a comprehensive drought resistance evaluation framework for Tibetan hulless barley. Furthermore, this study provides valuable insights for optimizing cultivation practices and water resource management strategies, offering theoretical guidance for agricultural adaptation to climate change. Full article

Abscisic acid (ABA)-stress-ripening, or ABA-, stress-, and ripening-induced (ASR) proteins play an important role in responses to environmental stimuli. A total of ten barley HvASRs were identified in this study, which were unevenly distributed on three chromosomes. ASRs from barley, wheat, Brachypodium distachyon, rice, maize, foxtail millet, and tomato were classified into two distinct clusters based on phylogenetic analysis. Notably, ASRs from Poaceae were evenly distributed between these two clusters. HvASRs contained a typical ABA/WDS domain, and exhibited similar motif arrangements. Two gene pairs of tandem duplicates (HvASR4/5/6/7 and HvASR8/9) were identified among HvASRs. Cis-acting elements involved in hormone and stress responses, including ABRE, MYB, ARE, and STRE, were consistently identified in the promoters of HvASRs. The expression of HvASRs was substantially influenced by salt, osmotic, and ABA treatments in the roots and leaves of barley seedlings. HvASR2 acts as a transcriptional repressor, whereas HvASR3 serves as a transcriptional activator. These results enhance our understanding of the HvASR family and provide a foundation for further functional characterization. Full article

Plasma-assisted treatment is a potentially interesting technology for advanced seed processing. In this work, we address the issue of defining and quantifying the plasma dose during the exposure of seeds to microdischarges formed in a barrier discharge configuration fed with synthetic air at atmospheric pressure. Using advanced imaging and other optoelectrical diagnostics, we identify suitable conditions for the formation of microdischarges developing exclusively between the powered electrode and the seed coat, which allows for the relatively accurate quantification of the plasma dose for an individual barley seed. In addition to determining the microdischarge energy/power consumed to treat a single seed during controlled exposure, we also provide an estimate of the electric field and gas temperature, which are key parameters that can affect seed viability. In this way, each individually exposed seed can be linked to the exact exposure time, total number, energy, and temperature of the microdischarges that came into contact with it. This is fundamentally different from conventional “averaging” approaches based on the simultaneous exposure of many seeds, which makes it virtually impossible to correlate the responses of individual seeds with the corresponding individual plasma dose. Finally, we propose a minimal treatment protocol that could allow for the more direct interpretation of the results of subsequent biological tests to reveal seed responses to specific plasma–chemical stimuli during germination and seedling growth. Full article

Salt stress is one of the most important abiotic stress factors that negatively affects sustainable crop production, agricultural productivity, and microbial life. Increasing salt stress negatively affects the growth and development of barley, posing a threat to global food security. It is now known that inoculation of plant growth-promoting rhizobacteria (PGPR) has significant potential in increasing stress tolerance and yield in agricultural products. This study focused on the effects of Bacillus cereus CUN6 and Bacillus thuringiensis SIRB2, isolated from the coastal zone and tested for their PGPR capacities, on physiological (root length, shoot length, biomass, dry weight) and biochemical (total chlorophyll, total protein, hydrogen peroxide, lipid peroxidation, peroxidase activity (POX), catalase activity (CAT)) analyses in Hordeum vulgare L. seedlings under salt stress. The results showed that the two bacterial inoculations alleviated the negative effects of salt stress by increasing the root-shoot length, biomass, dry weight, chlorophyll content, and total protein content in barley plants. However, B.thuringiensis increased growth and development especially in root length, biomass, and dry weight compared to B.cereus. On the other hand, B.cereus significantly increased root length, biomass, and chlorophyll content under salt stress; these increases were 17%, 5%, and 7%, respectively. B.thuringiensis chlorophyll content increased by 4% in 300 mM NaCl compared to the control. When compared in terms of the antioxidant defense system, B.thuringiensis inoculation was more effective on CAT activity, while B.cereus inoculation was more effective on POX activity. Under salt stress, B.cereus and B.thuringiensis inoculation significantly decreased H₂O₂ content in barley; these decreases were 16% and 10%, respectively. Additionally, TBARs content was significantly decreased by B.cereus and B.thuringiensis inoculation under salt stress; these decreases were determined as 8% and 9%, respectively, compared to the control. These results indicated that both bacterial inoculations can alleviate the salt tolerance of barley seedlings by regulating antioxidant metabolism. This research focused on the potential of B.cereus and B.thuringiensis as biofertilizers against salt stress in barley based on physiological and biochemical analysis. Full article

Advances in combinatorial synthesis and high-throughput screening methods have led to renewed interest in synthetic plant immunity activators as well as priming agents. 3,5-Dichloroanthranilic acid (3,5-DCAA) is a derivative of anthranilic acid that has shown potency in activating defence mechanisms in Arabidopsis and barley. Chemical biology, which is the interface of chemistry and biology, can make use of metabolomic approaches and tools to better understand molecular mechanisms operating in complex biological systems. Here we report on the untargeted metabolomic profiling of barley seedlings treated with 3,5-DCAA to gain deeper insights into the mechanism of action of this resistance inducer. Histochemical analysis revealed the production of reactive oxygen species in the leaves upon 3,5-DCAA infiltration. Subsequently, methanolic extracts from different time periods (12, 24, and 36 h post-treatment) were analysed by ultra-high-performance liquid chromatography hyphenated to a high-resolution mass spectrometer. Both unsupervised and supervised chemometric methods were used to reveal hidden patterns and highlight metabolite variables associated with the treatment. Based on the metabolites identified, both the phenylpropanoid and octadecanoid pathways appear to be main routes activated by 3,5-DCAA. Different classes of responsive metabolites were annotated with flavonoids, more specifically flavones, which were the most dominant. Given the limited understanding of this inducer, this study offers a metabolomic analysis of the response triggered by its foliar application in barley. This additional insight could help make informed decisions for the development of more effective strategies for crop protection and improvement, ultimately contributing to crop resilience and agricultural sustainability. Full article

The goal of the current study was to investigate the effects of seed priming with salicylic acid (SA) on seed germination parameters, seedling growth traits, nutritional element mobilization, and oxidative stress status in two barley species that were subjected to various salt treatments. The findings demonstrated that salinity reduced a number of germination parameters in unprimed seeds and impacted seedling growth by impeding both species’ necessary nutrient mobilization. Under this abiotic stress, a noticeable rise in malondialdehyde and electrolyte leakage was also noted. Interestingly, pretreating seeds with SA improved seed germination and seedling growth performance under either 100 mM or 200 mM NaCl treatments. In fact, SA improved the length and dry weight of stressed seedlings of both barley species in addition to increasing the germination rate and mean daily germination. Additionally, SA increased the content of calcium, iron, magnesium, and potassium while lowering the concentrations of sodium and malondialdehyde and electrolyte leakage. It is significant to note that, in comparison to Hordeum maritimum, the positive effects of this hormone were more noticeable in stressed Hordeum vulgare species. Full article

Many endophytic fungi are approved as plant growth stimulants, and several commercial biostimulants have already been introduced in agricultural practice. However, there are still many species of fungi whose plant growth-promoting properties have been understudied or not studied at all. We examined the growth-promoting effect in spring barley (Hordeum vulgare) and Italian ryegrass (Lolium multiflorum) induced by three endophytic fungi previously obtained from the roots of Festuca/Lolium grasses. Surface-sterilized seeds were inoculated with a spore suspension of Cadophora fastigiata (isolate BSG003), Paraphoma fimeti (BSG010), Plectosphaerella cucumerina (BSG006), and their spore mixture. Before harvesting, the inoculated plants were grown in a greenhouse, with the barley being in multi-cavity trays for 30 days and ryegrass being placed in an original cylindric element system for 63 days. All three newly tested fungi had a positive effect on the growth of the barley and ryegrass plants, with the most pronounced impact observed in their root size. The fungal inoculations increased the dry shoot biomass between 11% and 26% in Italian ryegrass, but no such impact was observed in barley. The highest root increment was observed in barley. Herein, P. cucumerina and C. fastigiata inoculations were superior to other treatments, showing an increase in root dry weight of 50% compared to 20%, respectively. All fungal inoculations significantly promoted root growth in Italian ryegrass, resulting in a 20–30% increase in dry weight compared to non-inoculated plants. Moreover, a strong stimulatory effect of the fungi-emitted VOCs on the root development was observed in plate-in-plate arrays. In the presence of C. fastigiata and P. cucumerina cultures, the number of roots and root hairs in barley seedlings doubled compared to control plants. Thus, in our study, we demonstrated the potential of the grass root-derived endophytes C. fastigiata, P. fimeti, and P. cucumerina as growth promoters for spring barley and Italian ryegrass. These studies can be extended to other major crops and grasses by evaluating different fungal isolates. Full article

Drought is becoming more prevalent and negatively affects the growth and development of barley. To explore the genetic variation in barley under drought stress, ten breeding genotypes were tested using polyethylene glycol-6000 to simulate drought conditions. We observed that drought stress significantly affected germination-related traits, depending on the specific genotypes. Some parameters, such as root length, reduced by up to 85% under drought conditions compared to the control. Overall, considering the barley growth performance, the drought tolerance index was an ideal criterion for selecting drought-tolerant genotypes, as it well characterized the gradient responses of barley genotypes to drought stress. Based on this indicator, genotype OB1878-ON-50 is recommended as a significant germplasm resource for low-precipitation regions. Full article

Barley (Hordeum vulgare L.), a major cereal crop grown in arid and semi-arid regions, faces significant yield variability due to drought and heat stresses. In this study, the HvABF2 gene, encoding an ABA-dependent transcription factor, was cloned using specific primers from water deficit-stressed barley seedlings. Gene expression analysis revealed high HvABF2 expression in developing caryopses and inflorescences, with significant induction under stress conditions. The HvABF2 coding sequence was utilized to generate transgenic barley plants with both stress-inducible and constitutive expression, driven by the rice SNAC1 and maize Ubiquitin promoters, respectively. Selected transgenic barley lines, along with control lines, were subjected to water deficit-stress experiments at seedling and flag leaf stages under controlled and greenhouse conditions. The transgenic lines exhibited higher relative water content and stomatal resistance under stress compared to control plants. However, constitutive overexpression of HvABF2 led to growth retardation under well-watered conditions, resulting in reduced plant height, grain weight, and grain number. In contrast, stress-inducible expression mitigated these effects, demonstrating improved drought tolerance without adverse growth impacts. This study highlights that the stress-inducible expression of HvABF2, using the SNAC1 promoter, effectively improves drought tolerance while avoiding the negative pleiotropic effects observed with constitutive expression. Full article