Search Results (2,044)

Yellow rust (Puccinia striiformis f. sp. tritici) is one of the most destructive diseases in wheat (Triticum aestivum L.) in Kazakhstan, causing significant yield losses. Owing to the high susceptibility of widely cultivated varieties, the development of resistant genotypes remains a key objective for sustainable crop protection. The aim of this study was to evaluate the resistance of wheat lines to yellow rust and to identify effective resistance genes. The research was conducted under artificial infection conditions using hybrid populations of the F2–F5 generations. The genotypes were assessed and ranked according to their resistance levels, and molecular markers were applied to detect resistance genes. Significant variability in disease response was observed. Analysis of variance revealed a strong effect of genotype on the infection coefficient (p < 0.001). Lines from later generations (F5) presented lower infection levels. Most genotypes carried the Yr5 gene, highlighting its major role in resistance, whereas Yr10 was less common. Yr15 and Yr18 were detected in some lines and were associated with partial (adult plant) resistance. Moderately susceptible forms predominated, indicating widespread quantitative resistance. However, highly resistant lines (CI = 0–1) and immune forms were identified, representing valuable material for breeding programs. Full article

Protein nitration within the nitro-proteome is a dynamic component of drought and recovery responses in wheat (Triticum aestivum L.), yet its role in stress adaptation remains unclear. Young wheat seedlings demonstrate a degree of drought resistance, characterized by physiological and morphological adaptations, during the initial growth phases. However, this tolerance begins to diminish significantly in 5-day-old seedlings. The mechanisms behind this phenomenon are unclear. Our results indicate that it may be related to protein nitration. This study compared the physiological and nitrosative responses of 4-day-old drought-tolerant and 6-day-old sensitive wheat seedlings subjected to drought followed by rehydration. In tolerant seedlings, in contrast to sensitive ones, the water saturation deficit after rehydration returned to the control levels, confirming their drought tolerance. Moreover, NO₂⁻ accumulation in the recovery group was significantly higher in sensitive seedlings than in the control group. Results indicate that drought resistance correlates with protein nitration during the recovery phase. Nitro-proteomic analysis revealed that in tolerant seedlings, protein nitration is limited. The most significant differences are observed in the recovery group, with predominant downregulation of protein nitration in tolerant seedlings and significant upregulation of numerous proteins in sensitive seedlings. Upregulated nitration of vital proteins involved in energy production, photosynthesis (such as the Rubisco large subunit), ATP synthases, and cytosolic malate dehydrogenase may lead to disturbances in energy metabolism and thus prevent an effective response to changing environmental conditions. These findings suggest that regulation of protein nitration during recovery may contribute to drought resilience in wheat and could represent a potential target for improving stress tolerance. Full article

Driven by increasingly severe drought stress associated with global warming, this study investigated a synthetic microbial community, SynCom-SASW01, with strong stress tolerance and plant growth-promoting potential, and systematically elucidated its mechanisms for enhancing drought resistance in wheat (Triticum aestivum L.). Dual-site field trials demonstrated that SynCom-SASW01 significantly alleviated drought-induced growth suppression, increasing grain yields by 10.42% and 8.52% at the Hohhot and Hulunbuir sites, respectively. This improvement was primarily associated with increased effective tiller number and enhanced root vigor. Physiologically, inoculation promoted root proline and glutathione accumulation and enhanced antioxidant enzyme activities, including superoxide dismutase, thereby reducing malondialdehyde levels. Environmental analyses showed that the consortium established rhizosphere “micro-reservoirs” through exopolysaccharide secretion, improving soil relative water content and the availability of alkali-hydrolyzable nitrogen and phosphorus. High-throughput sequencing revealed that SynCom-SASW01 reshaped the endosphere microbiome through early colonization priority effects, selectively enriching beneficial taxa such as Pseudomonas. Functional prediction indicated upregulated branched-chain amino acid biosynthesis, promoting osmotic adjustment and redox homeostasis. These findings provide a microbiome-based strategy for stabilizing wheat productivity in arid regions. Full article

Identifying superior salt-tolerant germplasm and resistance genes is crucial, as wheat (Triticum aestivum L.) seedlings are highly vulnerable to salt stress. Here, using an optimized 150 mM NaCl treatment, we screened 137 Chinese wheat accessions via an organ-specific method. Phenotyping analysis revealed extensive organ-specific divergence, with 48.91% of accessions displaying inconsistent performance between shoot and root length. We then performed comparative transcriptomics on three representative phenotypes at the seedling stage: Gaoyou 2018, representing the salt dual-sensitive group; Huapei 5, representing the salt dual-tolerant group; and Jimai 60, representing the divergent group with higher tolerance in shoots rather than in roots. Analysis of overlapping differentially expressed genes (DEGs) across all three accessions revealed a basal stress response—characterized by induced osmotic defense and suppressed primary growth—exemplifying a classical growth–defense trade-off. Genotype-specific DEG profiling demonstrated that the divergent Jimai 60 maintains its shoot advantage by reinforcing physical barriers and inhibiting apoptosis. Conversely, transcriptomic profiling implies that the systemically tolerant Huapei 5 maintains coordinated shoot and root tolerance at the seedling stage by strongly activating below-ground Na⁺ homeostasis (efflux and compartmentalization) while simultaneously down-regulating non-essential immune responses to optimize defense energy reallocation. Collectively, our findings provide novel insights into the organ-differentiated salt tolerance of wheat, offering well-characterized elite germplasm and compelling genetic targets for future molecular breeding. Full article

Soil salinity is a major constraint on global wheat productivity, yet the genetic and molecular determinants of root system architecture (RSA) adaptation under salt stress remain poorly characterized. We integrated a genome-wide association study (GWAS) of 566 wheat accessions with comparative RNA-seq transcriptomics to identify the genetic and transcriptional determinants of RSA adaptation under 200 mM NaCl. GWAS identified a candidate locus on chromosome 7B harboring TaIAO, which encodes a protein with predicted aldehyde oxidase-like activity consistent with a role in tryptophan-dependent auxin biosynthesis. Accessions carrying the favorable CC allele exhibited significantly greater root volume retention than those carrying the GG genotype (p < 0.001). Comparative RNA-seq revealed that the salt-tolerant Sarajevo 1 exhibited coordinated transcriptional repression of three distinct modules—cell wall expansion (TaExpansin), auxin redistribution (TaPIN-like), and stress-associated ROS defense (TaPOD1)—whereas the sensitive genotype CI 17260 aberrantly induced or incompletely repressed these modules under stress. ELISA-based IAA quantification, ROS imaging, and qRT-PCR analysis provided independent physiological and transcriptional support for these patterns. These findings support a two-tier adaptive model in which constitutive genetic variation at the TaIAO locus may contribute to a developmental baseline, coupled with coordinated stress-responsive transcriptional repression of energy-consuming modules, providing promising targets for marker-assisted breeding of salt-tolerant wheat. Full article

Identifying soil nutrient limiting factors and fertilization effects in the irrigated silty soil region of Ningxia is key to improving wheat (Triticum aestivum L.) quality and yield. A field experiment was conducted with five treatments: conventional fertilization (TF), recommended fertilization (RF), nitrogen deficiency (RF-N), phosphorus deficiency (RF-P), and potassium deficiency (RF-K). The results showed that under RF, soil nutrients remained at relatively high levels, with no significant differences compared with TF. In contrast, RF-N significantly reduced soil mineral nitrogen, total nitrogen, and organic matter compared with TF, and inhibited plant growth, photosynthesis, and plant accumulation of nitrogen, phosphorus, and potassium. Wheat yields under RF and RF-K showed no significant differences from those under TF, whereas RF-N and RF-P significantly reduced yields by 42.68% and 22.69%, respectively, relative to RF, mainly due to decreases in spike length and grain number per spike. The increase in yield was associated with synergistic increases in grain number per spike, spike number per hectare, and spike length. Yield components were significantly positively correlated with soil organic matter, total phosphorus, and mineral nitrogen, with soil total phosphorus identified as the environmental factor most strongly associated with wheat yield. Grain protein content was significantly positively correlated with soil mineral nitrogen, while starch content was significantly negatively correlated, indicating that mineral nitrogen is a key factor regulating grain quality. In summary, nitrogen fertilizer is the primary limiting factor in this region. Applying nitrogen, phosphorus, and potassium together synergistically enhances wheat yield by increasing soil total phosphorus levels and improves grain quality by regulating soil mineral nitrogen. Thus, this combined fertilization strategy provides a foundation for precise nutrient management and the simultaneous improvement of both yield and quality. Full article

Saline irrigation is increasingly practiced in semi-arid regions to cope with freshwater scarcity; however, it strongly affects crop growth, water use, and soil salinity. This study aims to calibrate and validate the AquaCrop model to simulate key growth parameters of winter wheat (cv. Achtar) under saline irrigation conditions in the Tadla Plain, Morocco, focusing on canopy cover (CC), actual evapotranspiration (ETa), soil water content (SWC), biomass (B), and grain yield (GY). The model was first calibrated using observed data from the 2023 growing season and subsequently validated using data from the 2022 growing season. Overall, AquaCrop effectively reproduced crop growth during both calibration and validation phases. During calibration, canopy cover was accurately simulated, with average RMSE values below 1%, while biomass and grain yield were also well reproduced, with low RMSE values (0.25 t ha⁻¹ for B and 0.10 t ha⁻¹ for GY), confirming the robustness of the calibrated parameters. The model also performed well in simulating ETa and SWC, capturing the seasonal dynamics of crop water use and soil moisture. During validation, ETa was satisfactorily reproduced, with an RMSE of approximately 0.80 mm day⁻¹, while SWC showed good agreement with observations, with NRMSE values ranging from 7.9 to 10.5%. Grain yield and biomass were reliably predicted, with NRMSE values below 4%. These results demonstrate that AquaCrop is a reliable tool for simulating winter wheat under saline irrigation and for assessing crop response under salt-affected conditions, providing an integrated evaluation of crop performance, water use, and soil salinity dynamics to support improved irrigation management and water-use efficiency under semi-arid conditions. Full article

Heat stress severely constrains wheat productivity, yet the mechanisms underlying thermotolerance remain incompletely understood. This study integrated physiological, biochemical, molecular, and ultrastructural analyses to characterize heat-stress responses in four bread wheat (Triticum aestivum L.) genotypes contrasting in heat tolerance. Membrane injury was assessed by membrane damage rate, lipid peroxidation by malondialdehyde accumulation, antioxidant defense by SOD, CAT, GPX, and BPX activities, and stress-responsive regulation by qRT-PCR analysis of DREB, HSP16.9, and SOD isoforms. HSP16.9 protein accumulation was further evaluated by Western blotting. Heat stress increased membrane damage and MDA accumulation in all genotypes; however, tolerant Murov 2 and Zirva 85 showed lower oxidative membrane injury than sensitive Aran and Gyzyl bugda. Thermotolerance was associated with stronger antioxidant activation, enhanced DREB and HSP16.9 induction, and more coordinated FeSOD and MnSOD expression. The HSP16.9 protein accumulated after heat treatment, supporting its role as a stress-responsive molecular chaperone. Separate correlation analyses of tolerant and sensitive genotypes revealed stronger coordination among transcriptional, chaperone-related, and antioxidant markers in tolerant genotypes, whereas sensitive genotypes showed a more fragmented response. Microscopy further showed better preservation of chloroplast, mitochondrial, and mesophyll organization in the tolerant genotype relative to the sensitive counterpart, indicating integrated cellular protection. Together, these responses define a coordinated tolerance strategy that may guide the selection of heat-resilient wheat genotypes. Full article

Sowing density affects the tillering and the number of spikes, which are important wheat yield components. Meanwhile, biostimulants stimulate plant growth and development, which usually improves the yield and grain quality. In our experiment, we investigated the impact of different grain sowing densities (200, 250, 300, 350, 400 and 450 grains m⁻²) and the timing of application of Methylobacterium symbioticum Pascual et al. 2021 bacteria (control, tillering, stem elongation) on winter wheat (“RGT Kilimanjaro” variety) grain yield size and quality. The three-year experiment (2022/2023–2024/2025) was conducted in a split-plot design. The content of macroelements in the soil (Haplic Cambisol) was high, and the contents of micronutrients were medium or low. It was shown that varied weather conditions modified plant responses in individual years. In general, along with the increase in canopy density, the physiological parameters of plants (Fv/Fm, Fv/Fo, PI, RC/ABS), gas exchange parameters (Gs, E, Ci, PN) and SPAD index values. The highest grain yield was obtained in 2023, and the yield in 2025 was significantly lower by 0.39 t ha⁻¹. On average, in the conducted experiment, the best results were obtained with a sowing density of 350 grains m⁻² and 400 grains m⁻². The yields obtained at these densities were 8.21 t ha⁻¹ and 8.34 t ha⁻¹, respectively. However, the highest protein content (14.6%) was identified at a sowing density of 300 grains m⁻². The application of M. symbioticum bacteria, especially in the stem elongation stage, had a positive effect on the yield as well as on the grain protein and gluten content. In contrast, antioxidant capacity was generally higher in the control treatment, while total phenols and flavonoids were most favorably affected by biostimulant application at the tillering stage. PCA and Pearson correlation analysis revealed an inverse relationship between physiological performance and antioxidant-related traits, indicating that climatic variability played an important role in modulating bioactive compound accumulation. Overall, moderate sowing densities combined with M. symbioticum application at stem elongation improved wheat productivity and grain quality, while antioxidant-related traits were mainly influenced by environmental conditions. Full article

Cuticular wax mixtures are the major components of the lipophilic cuticle coating of plant aerial organs during primary growth and they protect plants from environmental stresses. Decoding cuticular wax biosynthesis in bread wheat (Triticum aestivum L.) could contribute to the genetic improvement of this agriculturally important crop. Herein, we revealed that the wheat MYB46-like transcription factor TaMYB46 positively regulates cuticular wax by activating transcription of the long-chain acyl-CoA synthetase 1 (TaLACS1) gene. Knockdown of the wheat TaMYB46 gene resulted in significantly reduced cuticular wax loads and increased permeability of the wheat leaf cuticle. Furthermore, wheat long-chain acyl-CoA synthetase TaLACS1 was identified as a core component of the cuticular lipid biosynthetic machinery. Knockdown of the TaLACS1 gene led to reduced cuticular wax accumulation and increased leaf cuticle permeability. Moreover, the transcription factor TaMYB46 was found to enrich at the TaLACS1 promoter regions and activate TaLACS1 gene transcription. These findings collectively support the conclusion that the transcription factor TaMYB46 stimulates cuticular wax biosynthesis, likely by activating TaLACS1 transcription. Full article

Optimizing the interaction between planting density and nitrogen (N) application rate is critical for simultaneously improving grain yield and nitrogen use efficiency (NUE) in winter wheat (Triticum aestivum L.). However, the underlying regulatory mechanism remains poorly understood in the fluvo-aquic soil region of the southern Huang–Huai–Hai Plain. This study aimed to elucidate the physiological mechanism by which planting density and nitrogen application interactively regulate source–sink coordination to achieve synergistic high grain yield and high NUE, and to screen the optimal local cultivation combination for winter wheat in southeastern Henan. A two-year consecutive field experiment was conducted from 2018 to 2020 in Shangshui, Henan, using a split-plot design. Three planting densities (D1: 225 × 10⁴ plants ha⁻¹; D2: 375 × 10⁴ plants ha⁻¹; D3: 525 × 10⁴ plants ha⁻¹) and five N rates (N0: 0; N1: 180; N2: 240; N3: 300; N4: 360 kg N ha⁻¹) were established. Results demonstrated that planting density, N rate, and their interaction significantly regulated grain yield, NUE, and dry matter and N allocation, with consistent trends across both years. Increasing density enhanced total biomass and N accumulation, but dry matter and N partitioning to grains declined when density exceeded 375 × 10⁴ plants ha⁻¹. Grain yield exhibited a quadratic response to N rate; the optimal N rate for maximum yield decreased from 296.33 kg ha⁻¹ at low density (D1) to 237.50–245.38 kg ha⁻¹ at medium and high densities. The combination of 240 kg N ha⁻¹ and 375 × 10⁴ plants ha⁻¹ (D2N2) produced the highest average grain yield (8875.35 kg ha⁻¹), with simultaneous improvements in spike number and kernels per spike as well as superior dry matter and N partitioning to grains. This combination also maintained high nitrogen recovery efficiency (NRE) and nitrogen agronomic efficiency (NAE). Correlation analysis revealed that grain yield and NUE were significantly positively correlated with dry matter accumulation, N accumulation, and their partitioning proportions to grains. Overall, D2N2 achieved simultaneous high yield and high NUE by coordinately optimizing dry matter and N partitioning to grains. We therefore recommend reducing N fertilizer to approximately 240 kg ha⁻¹ combined with a moderate planting density of 375 × 10⁴ plants ha⁻¹ as the preferred strategy for sustainable and intensive winter wheat production in the fluvo-aquic soil region of southeastern Henan and adjacent areas. Full article

Background/Objectives: NPF proteins are important transporters that mediate nitrate uptake, nutrient allocation, and abiotic stress responses in plants. However, the evolutionary patterns of the NPF gene family in grasses remain largely unclear. This study aimed to clarify the evolutionary expansion and stress response characteristics of NPF genes in Poaceae. Methods: A comprehensive comparative genomic analysis was conducted across nine representative Poaceae species and Arabidopsis thaliana. Multiple analytical approaches were used, including gene family identification, phylogenetic classification, collinearity analysis, Ka/Ks calculation, cis-element prediction, protein interaction analysis, and RNA-seq expression verification. Results: A total of 1109 NPF genes were identified with substantial variation in gene copy number among species, particularly the remarkable expansion observed in hexaploid Triticum aestivum. Phylogenetic analysis classified grass NPF proteins into eight major subfamilies, while collinearity analyses revealed that whole-genome duplication and segmental duplication were the primary drivers of NPF expansion. Most duplicated gene pairs exhibited Ka/Ks values below 1, indicating strong purifying selection during evolution. Promoter analyses identified abundant stress- and hormone-responsive cis-elements, especially in Triticeae species. In addition, protein–protein interaction and RNA-seq analyses suggested potential functional associations among NPF genes and revealed expression variation under low-temperature treatments in rice and wheat. Conclusions: Collectively, this study objectively clarifies the evolutionary expansion, functional conservation, and potential stress-responsive diversification of the NPF gene family in grasses. These findings provide straightforward and reliable insights for further evolutionary and functional research on the NPF gene family in Poaceae. Full article

Climate change has intensified the occurrence of combined abiotic stresses such as drought, salinity, heat, and waterlogging, thereby threatening cereal productivity and global food security. Root systems play a central role in plant adaptation to these interacting stresses by regulating water uptake, ion balance, nutrient acquisition, and stress signaling. However, many previous studies have primarily focused on individual stress factors rather than integrated stress environments. This review synthesizes current knowledge regarding root-mediated adaptive mechanisms in cereal crops under combined abiotic stresses, with emphasis on barley (Hordeum vulgare), wheat (Triticum aestivum), and oats (Avena sativa). The review highlights how root system architecture, including root depth, branching density, and aerenchyma formation, contributes to stress resilience under interacting environmental conditions. Physiological and molecular mechanisms involving ion transporters, aquaporins, transcription factors, and auxin-regulated root plasticity are also discussed. In barley, deeper and steeper root systems improve water acquisition under combined drought and heat stress, while wheat genotypes carrying the HKT1;5 allele exhibit enhanced sodium exclusion under drought–salinity interactions. Oats respond to waterlogging and salinity through adventitious root formation and enhanced oxygen transport. Overall, this review emphasizes the importance of root-targeted approaches for improving cereal adaptation under increasingly complex multi-stress environments. Full article

Agroecosystems are perpetually subjected to environmental factors. Driven by a shifting global climate, soil moisture deficits represent an increasingly frequent threat to crop productivity. In farming, however, these abiotic stressors seldom occur in isolation, as fields are invariably compounded by biotic weed pressure. Consequently, investigating plant responses to such combinatorial, multi-faceted stress is paramount to evaluating the realistic efficacy of modern agrotechnical interventions. A 2-year, three-factor pot experiment was conducted at the Research and Education Station in Swojczyce, belonging to the Wrocław University of Environmental and Life Sciences. The aim of the study was to examine the response of winter wheat (Triticum aestivum L., cv. Agil) to drought stress during the period when cereal plants were at the 51–65 BBCH developmental stages. Additionally, in some pots with winter wheat, Apera spica-venti (L.) Beauv. was sown as a weed to evaluate the effects of biotic stress. To observe the mitigation of stressors, three different types of biostimulants were used—a silicon-based preparation and two seaweed-based preparations derived from Ecklonia maxima (Osbeck) Papenfuss and Ascophyllum nodosum (L.) Le Jolis, respectively, representing structural, morphological, and biochemical defense strategies. Drought stress significantly and negatively affected the length of the wheat main stem, lateral tillers, and lateral spikes, as well as the weight of the main wheat spike. The simultaneous occurrence of drought stress and A. spica-venti competition resulted in the greatest cumulative reduction in main spike weight. Furthermore, drought stress was associated with an increase in nitrogen/protein content and potassium content in wheat straw. The presence of A. spica-venti significantly reduced both the weight of the main wheat spike and the number of non-productive tillers. The limited effectiveness of biostimulants may be associated with the severity and timing of stress exposure during reproductive development. Full article

Compression tests are widely used to characterize cereal kernels, yet the loading rate is often treated as a secondary methodological factor, despite the fact that the ASAE S368.4 procedure recommends a low crosshead speed, whereas industrial size-reduction operations involve much faster and more complex loading conditions. This mismatch limits the direct transfer of laboratory data to milling practice and makes it difficult to compare results obtained under different test settings. The aim of this study was therefore to determine how grain moisture content and loading rate (crosshead speed) affect kernel damage and selected mechanical properties of bread wheat cultivars (Bataja and Tytanika) and feed wheat cultivars classified in the Polish C quality group (Lawina and Sikorka). Before the analyses, kernels were adjusted to five moisture levels: 10%, 12%, 14%, 16%, and 18% on a wet basis (w.b.). Compression tests were conducted at six crosshead speeds: 1, 3, 5, 10, 30, and 50 mm min⁻¹. The conversion ratio of mechanical properties determined relative to 1 mm min⁻¹ and 10% moisture content ranged from 0.46 to 2.59, confirming that both factors markedly changed kernel response. Rupture force generally decreased with increasing moisture content, whereas longitudinal strain, relative strain and rupture energy increased. A distinct decrease in all mechanical parameters was observed at 10 mm min⁻¹, and this effect became more pronounced at higher moisture contents. The results indicate that the loading rate should be reported and controlled in wheat kernel compression tests and should be considered when laboratory measurements are used to support milling optimization. However, the proposed value of 10 mm min⁻¹ should be interpreted as a promising laboratory reference point rather than as a direct industrial operating standard. Full article