Wheat (Triticum aestivum L.) grain is a treasure trove of bioactive phenolic compounds, including soluble and wall-bound (WB) phenolic compounds. Ferulic acid (FA) is dominant in WB phenolics and a standout due to its potent antioxidant capabilities. However, dietary FA often falls short of recommended intakes. This study investigated the content, trend, regulation, and potential of FA in a wheat germplasm collection. A large-scale screening of over 600 wheat germplasms from Pakistan and China revealed that some modern Chinese cultivars have high FA contents comparable to those of colored wheat. In contrast, Pakistani wheat cultivars have ample room for further increases in FA content. Transcriptome analyses pointed to a correlation between high expression levels of HXXXD-type acyl transferase genes and FA contents in developing grains. FA remained stable through various food processing methods, including the production of noodles, bread, and steamed buns. Moreover, fruit flies (Drosophila melanogaster) fed HFA foods had a longer lifespan than those fed LFA in both acute oxidative stress (5% H2O2) and chronic high-temperature (29 degrees C) stress. Therefore, biofortification of FA in wheat grains has a significant potential for health and can be achieved using the identified wheat germplasms. The above results provide candidate genes, promising parental lines, and a theoretical basis for future wheat breeding aimed at enhancing the antioxidant and health-promoting properties of wheat.

Leaf rust is among the most destructive diseases of wheat globally, incurring significant yield losses and serious economic damage. Characterization and fine mapping of genetic loci for leaf rust resistance can be beneficial for marker-assisted breeding. In the present study, we identified three stable quantitative trait loci (QTL) for adult-plant leaf rust resistance, designated QLr.caas-2AS, QLr.caas-2DS and QLr.caas-5AL, respectively, in a recombinant inbred line population derived from a Zhongmai 175 & times; Lunxuan 987 cross across four environments. Fine mapping of QLr.caas-5AL was subsequently conducted using a secondary population derived from 18 heterozygous recombinants and 19 Kompetitive allele-specific PCR (KASP) markers, which allowed the delimitation of the QTL to a 794.8-kb physical interval from 523.6 to 524.4 Mb based on the Chinese Spring reference genome v1.1. Eighteen high-confidence annotated genes were present in this physical interval, and three genes showing sequence polymorphisms and differential expression between parents were predicted as candidates for QLr.caas-5AL, based on genome and transcriptome sequencing analyses. A KASP marker for QLr.caas-5AL was successfully developed and validated to be significantly associated with leaf rust severity in a natural wheat population of 221 cultivars. The frequency of the resistance allele at this KASP marker locus was 48.0% in the wheat cultivar panel. These findings not only lay a robust foundation for map-based cloning of QLr.caas-5AL, but also provide an efficient molecular tool for marker-assisted selection in wheat breeding. (c) 2026 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Global climate change has led to increasingly frequent extreme weather events, including high temperatures, drought, and heavy rainfall, severely disrupting stable crop production. Concurrently, continuous global population growth intensifies food market demand, placing unprecedented pressure on global food security. As one of the most important staple cereal crops worldwide, wheat plays a central role in ensuring food supply, and persistent improvement of wheat yield potential has consistently remained a major long-term objective of modern breeding research. China ranks first globally in both wheat production and consumption; therefore, achieving stable yield increase and quality improvement is crucial to national food security and agricultural sustainable development. Traditional breeding technologies have contributed tremendously to the iterative yield improvement of wheat cultivars across different historical periods and have established a solid foundation for solving food shortage problems. Nevertheless, conventional breeding relies heavily on empirical phenotypic evaluation and artificial field selection, resulting in long breeding cycles, low selection efficiency, and poor predictability of complex quantitative traits. These constraints are insufficient to meet the rigorous requirements for the coordinated improvement of ultra-high-yield potential, stress-resistance, and high quality in modern wheat breeding. To overcome the long-standing bottleneck of stagnant wheat yield improvement caused by the narrowed genetic diversity of modern cultivars, synergistic innovation and breakthroughs of modern agricultural technologies are urgently needed. The integration of cutting-edge biotechnologies, including telomere-to-telomere (T2T) genome mining, gene editing, distant hybridization, and genome-wide selection, together with information technologies such as high-throughput phenotyping and artificial intelligence-based predictive models, has become the core driving force to achieve ultra-high-yield breeding goals. This paper systematically reviews the yield potential characteristics and evolutionary trends of wheat cultivars in the core Yellow & Huai River valley wheat-producing region, clarifies the structural optimization pathways underlying ultra-high yield formation, and summarizes the application progress of cutting-edge biotechnologies and digital information technologies in wheat genetic improvement. It further elaborates on the innovative achievements in germplasm resource development, precise trait modification, and heterosis utilization in wheat breeding. Furthermore, this study critically discusses in-depth the current technical bottlenecks limiting breakthroughs in wheat ultra-high yield breeding, as well as future development trends and key research directions of modern wheat breeding within an integrated biotechnology-information technology framework. The relevant results aim to provide a systematic theoretical foundation and practical technical reference for breaking the wheat yield ceiling, developing novel ultra-high-yield wheat varieties, and promoting the sustainable high-quality development of the wheat industry.

Aegilops tauschii (DD, 2n = 2x = 14) is a well-studied wild species because it is the D-genome donor of bread wheat. Morphologically intermediate accessions are special types that are different from ssp. tauschii (cylindrical spikes) and ssp. strangulata (moniliform spikes). The understanding of the evolution of the intermediate type is very limited. The morphology and genetic mismatching of subspecies structure has long been a puzzle for this species. The present study addressed this puzzle using the spikelet index as an objective criterion to score spike morphology. Afterwards, fluorescence in situ hybridization (FISH) karyotyping was used to analyse the subspecies structure. Among the 399 studied accessions, 238, 56 and 105 accessions had cylindrical, moniliform and intermediate spikes with mildly moniliform spikelets, respectively. All the F1 plants from 25 reciprocal crosses between ssp. tauschii (cylindrical spikes) and ssp. strangulata (moniliform spikes) showed intermediate spikes. Based on spikelet index (SI), the 336 accessions with SI data were clearly divided into two clusters, SI-C1 (low SI) and SI-C2 (high SI), which corresponded to the previously assembled phylogenetic lineages L1 and L2, respectively. FISH karyotyping using the probes oligo-pTa-535 and (CTT)10 also divided the 399 accessions into two clusters, FISH-C1 and FISH-C2, which perfectly matched SI-C1 and SI-C2. The FISH markers 2D-CTT-4 and 2D-535 could be used to accurately distinguish the two clusters. Twelve accessions had obvious chromosomal rearrangements, most of which originated from Iran. Comparison of FISH patterns between Ae. tauschii and 219 common wheat cultivars showed that the wheat D genome matched the FISH-C2 pattern; in particular, the intermediate-spike accessions from the southwestern and southern Caspian region showed FISH patterns resembling those of common wheat. In this study, the intermediate accessions were placed into ssp. strangulata. The treatment reconciles the botanical and genetic categorizations: ssp. tauschii is taxonomically aligned with the cytogenetic and molecular lineage designated SI-C1/FISH-C1/L1, whereas ssp. strangulata corresponds to SI-C2/FISH-C2/L2. The intermediate-spike accessions of ssp. strangulata from the southwestern and southern Caspian region made an important contribution to the wheat D genome.

To address the core breeding demand for greater seedling vigor in bread wheat (Triticum aestivum L.) varieties adapted to the uniform sowing system in China’s Huang-Huai Wheat Region, we aimed to dissect the genetic architecture and identify core candidate genes for shoot length (SL) and root length (RL) at the germination stage. A natural population consisting of 204 wheat accessions was genotyped using the 660K SNP array, and a genome-wide association study (GWAS) integrated with transcriptomic, metabolomic, and proteomic analyses of extreme phenotypic accessions was performed. Both SL and RL were typical quantitative traits with an extremely significant positive correlation. A total of 111 and 176 significant SNPs were associated with SL and RL, respectively, including 56 shared loci. Glutathione metabolism was identified as the conserved core pathway for both tissues, while photosynthesis–antenna proteins and phenylpropanoid biosynthesis were identified as tissue-specific pathways in shoots and roots, respectively. Finally, we identified 7 core candidate genes for SL and 13 for RL, including three pleiotropic genes regulating both traits. This study provides valuable genetic resources and key targets for the molecular breeding of wheat varieties specialized for uniform sowing.

Background The type II NAD(P)H dehydrogenase ( ND ) gene family, as key components of the non-phosphorylating alternative respiratory pathway in mitochondria, plays important roles in plant responses to various environmental stresses. The ND gene family has been well characterized in multiple species, yet comprehensive studies on this gene family in wheat remain unexplored. Results The study identified 16 ND genes, and evolutionary and syntenic analyses revealed that all three subfamilies of plant ND genes, NDA , NDB and NDC are present in wheat. Chromosomal distribution analysis demonstrated that TaNDAs and TaNDBs have homologs across all three subgenomes (A, B, and D), while TaNDC1 exists as a single copy exclusively on chromosome 7D. TaND genes within the same phylogenetic group exhibited similar gene structures and conserved motif distributions. Promoter analysis showed that TaNDs widely harbored cis -acting elements associated with hormone signaling, stress responses, growth and development. Expression profiling demonstrated that TaNDs exhibited strong response to hormones, biotic and abiotic stresses. It is noteworthy that under infections of powdery mildew and crown rot, the expression of TaNDC1 was suppressed, exhibiting a trend similar to that observed under SA treatment. Conversely, under Fusarium head blight (FHB) infection, its expression was strongly induced, mirroring the pattern seen under JA treatment. Functional studies demonstrated that silencing TaNDC1 reduced wheat resistance to FHB, confirming its positive regulatory role in FHB resistance. Additionally, we confirmed that TaNDC1 interacts with TaPFT, a protein encoded within the major FHB resistance locus Fhb1 . Conclusions This study enhance our understanding of the TaND gene family and identify TaNDC1 as a potential candidate gene for improving FHB resistance in wheat.

As wheat is a globally important staple crop, the molecular regulatory network underlying heterosis in wheat remains incompletely understood. The flag leaf is the primary source of photoassimilates during grain filling and plays a crucial role in yield formation. However, the genetic mechanisms linking flag leaf development to heterosis are still unclear. Transcriptomic analysis revealed dynamic transcriptional reprogramming during the anthesis to grain-filling transition, with a pronounced expression bias toward superior parental alleles in hybrids. Anthesis-stage non-additive dominance and grain-filling-stage additive enhancement synergistically orchestrated the temporal regulatory shift underlying heterosis. The dominant alleles from the superior parent accounted for more than 60

Wheat can readily accumulate the toxic metal cadmium (Cd) in its grains, which potentially poses a risk to human health via food chain. Applications of essential metals are effective strategies for limiting grain Cd accumulation. However, the effects of copper (Cu) or manganese (Mn) application on Cd uptake and accumulation in wheat are not well known. Here, we performed hydroponic experiments using two bread wheat (Triticum aestivum L., AABBDD) varieties. Solution application of Cu (S_Cu) and Mn (S_Mn) alone or foliar application of Cu (F_Cu) and Mn (F_Mn) alone did not alter the dry weights of roots and shoots when compared with control under Cd stress. Mineral analysis found that S_Cu reduced Cd concentrations of roots, shoots and whole plant by 64.02-70.38 %, 10.21-11.93 % and 46.48-48.29 %, respectively; while, it promoted root-to-shoot Cd translocation by 143.55-209.12 %. Although F_Cu did not reduce Cd concentration of roots, it caused decreases in Cd concentrations in shoots (21.96-24.73 %) and whole plants (15.81-17.14 %), as well as root-to-shoot Cd translocation (21.27-31.32 %). Subcellular distribution analysis showed that both S_Cu and F_Cu limited Cd distribution in the root cell wall and soluble fractions. They also decreased the cellulose concentration. On contrary, both S_Mn and F_Mn increased Cd uptake and accumulation in both varieties. RNA-seq analysis revealed that differentially expressed genes caused by Cu or Mn application were mainly involved in cell wall organization, and hemicellulose and cellulose metabolic processes. Cu application might upregulate the expression of TaYSL6 and downregulate the expression of TaIRT1 to limit Cd uptake and accumulation.

Polyploidization is a fundamental evolutionary process in plants, including bread wheat. In the present study, we performed a comprehensive genome-wide analysis of dynamic homoeologous gene divergence in Aikang58 (AK58), a modern elite polyploid wheat cultivar with a recently released reference genome, and in other wheat genomes, including landraces, synthetic wheat, and several breeding lines. Over 40% of transposable element (TE) families exhibit biased distribution across the three wheat subgenomes. Approximately 95.0% (113 421) of genes are co-located with TEs, and these variable TEs significantly contribute to homoeologous divergence. We found that about 80% of triad homoeologs are divergent due to differences in expression or sub-functionalization. In addition, subgenome divergence potentially promote polyploid wheat domestication and improvement by increasing favorable homoeoallele combinations. Our findings suggest that homoeolog divergence contributes to the adaptation, domestication, and improvement of hexaploid wheat. The contribution of subgenomic divergence to polyploid heterosis is also discussed. This study provides a valuable resource for the investigation of how TEs drive homoeologous divergence during wheat domestication and improvement.

Chasmanthium latifolium (Michx.) H.O.Yates is a popular ornamental plant native to southeastern North America. Genomic data and genetic studies related to Chasmanthium latifolium are limited. Therefore, the complete chloroplast genome of Chasmanthium latifolium was sequenced, assembled, and characterized in this study. The complete chloroplast genome was 138,934 bp in length and contained 105 unique genes (77 protein-coding genes, 24 tRNA genes, and 4 rRNA genes). Phylogenetic analyses showed that Chasmanthium latifolium and Chasmanthium laxum clustered into a separate clade with the closest affinity to the clade comprising Zeugites pittieri Hack and Lophatherum gracile Brongn. In conclusion, our study describes the complete chloroplast genome of Chasmanthium latifolium for the first time, contributing to a better understanding of its taxonomy and evolution.

Leaf traits are important factors affecting the photosynthetic capacity of crops. In Bainong 4199 (BN4199) and Aikang 58 (AK58) wheat, the role of leaf color and leaf thickness in improving wheat photosynthetic performance and its influence on material accumulation and yield were studied in the field environment. Compared with AK58, BN4199 has a deeper leaf color and thicker leaves. Further study on photosynthetic physiological characteristics showed that the photosynthetic capacity of BN4199 with deep color and thick leaves was higher than that of AK58 at flowering stage, 7 days after flowering, 15 days after flowering, and 20 days after flowering regardless of low light in the morning and evening or light at noon. During the flowering stage, the light saturation point and compensation point were 1% higher and 15.23% lower, respectively, in BN4199 than AK58. According to the diurnal variation in chlorophyll content in different growth stages, BN4199 was generally higher than AK58, and the chlorophyll content was the highest at each time point 7 days after flowering. The chlorophyll content was highest at each time point 7 days after flowering. Chlorophyll fluorescence parameters and light reflectance analyses indicated that BN4199 has significantly higher photosynthetic electron transport and population light energy absorption and utilization capacity than AK58. The 2-year field yields indicated significantly higher material accumulation in BN4199 than AK58. In summary, thick leaves with deep color were resistant to both strong light and weak light, thus, markedly increasing photosynthetic efficiency. Improvement in leaf color and leaf thickness might serve as an important index to enhance the photosynthetic performance of wheat, and achieve improvement and breeding of wheat with high light efficiency.

Wheat (Triticum aestivum L.), a staple crop of global significance, faces constant biotic stress threats, with powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) being particularly damaging. In this study, a multi-year single-site experiment was conducted to minimize the environmental impacts, and a five-level classification system was used to assess powdery mildew resistance. A 660K SNP array genotyped 204 wheat germplasms, followed by GWAS. SNP loci with a −log10(p) > 3.0 were screened and validated across repeats to identify those associated with powdery mildew (Pm) resistance. Twelve SNPs were consistently associated with Pm resistance across multiple years. Of these, three colocalized with previously reported Pm-resistance gene or QTL regions, and the remaining nine represented potentially novel loci. The candidate genes identified included leucine-rich repeat (LRR) and NB-ARC immune receptors, as well as pathogen-related, thioredoxin, and serine threonine-protein kinase genes. Overall, the SNP loci and candidate genes identified in this study provide a basis for further fine mapping and cloning of the genes involved in relation to Pm resistance.

Fusarium head blight (FHB), caused by Fusarium graminearum (F. graminearum), has become one of the most devastating wheat diseases, severely impacting both grain yield and quality. The resistance gene TaHis (encoding a histidine-rich calcium-binding protein), located at the major FHB resistance locus Fhb1, has been demonstrated to confer FHB resistance in wheat, although its underlying mechanism remains unclear. In this study, we screened a wheat yeast two-hybrid (Y2H) library and identified TaU11/U12-35K, a core component of the U12-type spliceosome (U11/U12 small nuclear ribonucleoprotein), as a novel interacting partner of TaHis. Their physical interaction was further confirmed by both Y2H and bimolecular fluorescence complementation assays. Barley stripe mosaic virus-induced gene silencing (BSMV-VIGS)-mediated knockdown of TaU11/U12-35K significantly enhanced FHB resistance in both resistant (Bainong 4299) and susceptible (Bainong 5819) cultivars compared to controls. Expression profiling revealed that TaU11/U12-35K was significantly downregulated upon F. graminearum infection in both cultivars, with consistently lower basal expression levels in Bainong 4299, suggesting a negative correlation between TaU11/U12-35K expression and FHB resistance. Collectively, our results demonstrate that TaU11/U12-35K physically interacts with TaHis and functions as a negative regulator of FHB resistance. This study provides new insights into the molecular mechanism of TaHis-mediated FHB resistance in wheat.

MicroRNA (miRNA) is a class of the endogenes negative regulator in plant, playing the pivotal role in numerous growth and developmental processes as well as diverse stress responses. Although the miRNA biosynthesis-related gene have been widely recognized across various plants, its significance is poorly understanded in wild emmer wheat (Tritum dicoccoides), particularly those involving in salt stress tolerance. In this study, 96 miRNA-related genes were obtained through a genome-wide search, including 54 AGOs (Argonautes), 29 DCLs (Dicer-likes) and 13 RDR (RNA-Dependent RNA Polymerases), respectively. Collinearity analysis revealed that polyploidization contributed to their expansion in wild emmer Additionally, analysis of genetic variations revealed a significant genetic bottleneck on them during the domestication of tetraploid wheat. Furthermore, 22 salt-responsive candidates were identified by expression pattern analysis. Integrated co-expression network and genome-wide association studies analysis(GWAS), TdAGO30 was found as a key genes involving in salt response. Finally, functional verification and RNA-seq analysis demonstrated that TdAGO30 negatively regulated salt tolerance by mediating osmotic regulation, hormone synthesis and ion transport. This study provided the useful information on the roles of miRNA-related genes in regulating salt tolerance in wild emmer wheat, which will contribute to improve salt tolerance through miRNA manipulation in wheat and other crops.

LMWgs Finder developed by this study was used to re-identify the LMW-GS genes in a total of 26 genomes across the grass family and several important and novel findings were obtained. LMW-GS are one of the primary components of wheat (Triticum aestivum L.) seed storage proteins, which have an important impact on wheat end-use quality traits. Identifying LMW-GS genes accurately within wheat genomes has consistently presented a significant challenge. LMWgsFinder developed by this study was used to re-identify the LMW-GS genes in a total of 26 genomes of the grass family. Apart from six species, a total of 291 LMW-GS genes were identified. Except for the two versions of the TaCS (Triticum aestivum Chinese Spring) genome, only 38.13

Powdery mildew (caused by Blumeria graminis f. sp. tritici (Bgt)) and leaf rust (caused by Puccinia triticina (Pt)) are prevalent diseases in wheat (Triticum aestivum L.) production. Thinopyrum ponticum (2n = 10x = 70, EeEeEbEbExExStStStSt) contains genes that confer high levels of resistance to these diseases. An elite wheat-Th. ponticum disomic substitution line, DS5Ag(5D), was developed in the Bainong Aikang 58 (AK58) background. The line was assessed using genomic in situ hybridization (GISH), oligo-nucleotide probe multiplex (ONPM) fluorescence in situ hybridization (FISH), and molecular markers. Twenty eight chromosome-specific molecular markers were identified for the alien chromosome, and 22 of them were co-dominant. Additionally, SNP markers from the wheat 660 K SNP chip were utilized to confirm chromosome identification and they provide molecular tools for tagging the chromosome in concern. The substitution line demonstrated high levels of resistance to powdery mildew throughout its growth period and to leaf rust at the adult stage. Based on the resistance evaluation of five F5 populations between the substitution lines and wheat genotypes with different levels of sensitivity to the two diseases. Results showed that the resistance genes located on 5Ag confered stable resistance against both diseases across different backgrounds. Resistance spectrum analysis combined with diagnostic marker detection of known resistance genes of Th. ponticum revealed that 5Ag contained two novel genes, Pm5Ag and Lr5Ag, which conferred resistance to powdery mildew and leaf rust, respectively. In this study, a novel wheat-Th. ponticum disomic substitution line DS5Ag(5D) was successfully developed. The Th. ponticum chromosome 5Ag contain new resistance genes for powdery mildew and leaf rust. Chromosomic—specific molecular markers were generated and they can be used to track the 5Ag chromosome fragments. Consequently, this study provides new elite germplasm resources and molecular markers to facilitate the breeding of wheat varieties that is resistant to powdery mildew and leaf rust.

Yield and quality are important for plant breeding. To better understand the genetic basis underlying yield- and quality-related traits in wheat (Triticum aestivum L.), we conducted the quantitative trait locus (QTL) analysis using recombinant inbred lines (RILs) and a high-density genetic linkage map with a 90 K array. In this study, a total of 117 QTLs were detected for spike number per area (SNPA), thousand grain weight (TGW), grain number per spike (GNS), plant height (PH), spike length (SL), total spikelet number (TSN), spikelet density (SD), grain protein content (GPC), and grain starch content (GSC). Among these QTLs, 30 environmentally stable QTLs for yield- and quality-related traits were detected. Notably, five QTL-rich regions (Qrr) for yield- and/or quality-related traits were identified, including the QTL-rich region on chromosome 4BS (QQrr.cau-4B) for eight traits (SNPA, GNS, PH, SL, TSN, SD, GPC, and GSC). The stable QTL-rich region QQrr.cau-4B was delimited into a physical interval of approximately 2.47 Mb. Based on the annotation information of the Chinese spring wheat genome v1.0 and parental re-sequencing results, the interval included twelve genes with sequence variations. Taken together, these results contribute to further understanding of the genetic basis of SNPA, GNS, PH, SL, TSN, SD, GPC, and GSC, and fine mapping of QQrr.cau-4B will be beneficial for gene cloning and marker-assisted selection in the genetic improvement of wheat varieties.

Optimizing fertilizer and water application and using standardized and clean production methods are important for achieving green and sustainable agricultural development. The study was conducted from 2018 to 2021, arranged in a split-plot experimental design. Three fertilization levels (main plots) and four supplementary irrigation treatments (secondary plots) were set through three consecutive years of field positioning experiments. Chemical compound fertilizer application levels were 750 kg ha(-1) (F1), 600 kg ha(-1) (F2), 450 kg ha(-1) (F3). Irrigation levels were as follows: no irrigation during the whole growth period after emergence (W0), irrigation only at jointing stage (W1), irrigation at jointing and anthesis stage (W2), irrigation at greening, jointing and anthesis stage (W3). The results indicated that the stem length of the base increased with the increase of irrigation and water and fertilizer, especially on the base stem node. There was a significant interaction between different fertilizer and water treatments. Correlation analysis revealed a significant negative correlation between stem strength and the stem lodging index. After anthesis, the lodging index was significantly lower in the F2 treatment than that in the F1 treatment. Moreover, the contribution of dry matter accumulation to the grain before anthesis was significantly higher under the W2 treatment than that under the W3 treatment but was significantly lower than that under the W0 treatment. Furthermore, the W2 treatment exhibited significantly greater fertilizer and water effects than those under the W3 treatment, irrigation benefit increased by 10.39 kg ha(-1) mm(-1), whereas the F2 treatment exhibited significantly greater effects than those of the F1 treatment. In terms of yield, grain yield of F2W2 treatment was significantly higher than that of F3W1 treatment. The maximum yield of F2W2 treatment over three years was 9900.05 kg ha(-1). Therefore, reducing the amount of fertilizer and adjusting the irrigation regimes can enhance wheat growth and yield and mitigate the risk of lodging in the field.

The continuous release of antibiotics into agroecosystems has raised concerns about the potential negative effects of antibiotic residues on crops. In this study, the toxicological effects of enrofloxacin (ENR) on wheat seedlings were analyzed using a combination of morpho-physiological, transcriptomic, proteomic, and metabolomic approaches. ENR inhibited the growth of wheat (Triticum aestivum L.) roots and induced oxidative stress. In particular, ENR downregulated the oxidative phosphorylation pathway, while it enhanced glycolysis and the tricarboxylic acid cycle, thereby regulating the balance of intracellular energy metabolism. In addition, sustained exposure to excessive reactive oxygen species (ROS) resulted in an increase in reduced glutathione (GSH), a slight decrease in ascorbic acid (AsA), and a significant decrease in the ratio of GSH to oxidized glutathione (GSSG), which imbalanced the AsA-GSH cycle. In addition, the resulting increase in abnormal proteins triggered ubiquitin-independent proteasomal degradation pathways. Further, an increase in abscisic acid (ABA) and a decrease in jasmonic acid (JA) and its derivatives alleviated the inhibitory effect of ENR on the growth of wheat roots. In conclusion, direct damage and signaling by ROS, hormonal regulation, a decrease in the GSH to GSSG ratio, and insufficient energy supply were identified as key factors for the significant inhibition of wheat root growth under ENR stress.

Increasing wheat (Triticum aestivum L.) planting density is the most effective production management method for increasing yields; however, excessive crop populations under high planting densities may experience elevated risk of stem lodging. We conducted this study to assess the relationship between reduced lodging and increased yield, investigate the effects of planting density on wheat population structure, stem strength, and material transport, and provide a basis for rationale planting densities. The experiments were carried out using a split-plot design with three replicates. The main plots contained two wheat varieties: Bainong 5819 (BN5819) and Bainong 4199 (BN4199), and the sub-plots contained four planting density treatments: 90 × 104 plants/ha (D1), 180 × 104 plants/ha (D2), 270 × 104 plants/ha (D3), and 360 × 104 plants/ha (D4). A two-year field trial was conducted in 2021–2023. The relationships between population structure characteristics, changes in stem strength, activation, and retransport of stem material after anthesis, and achievement of high and stable yields were investigated at the different planting densities. When the planting density of wheat increased from D1 to D4 treatment, the activity of fructan hydrolase was significantly increased. Compared with D1 treatment, the highest activity of fructan hydrolase was increased by 457.47 μg/h/g under D4 treatment. At the same time, the increase of density also increased the contribution rate of dry matter accumulation (CDMA) to grain after anthesis increased, with the highest increase in CDMA at 33.67%, which significantly reduced stem strength. Correlation analysis revealed a significant negative association between CDMA and stem strength. Specifically, CDMA levels were significantly lower with the D3 treatment than the D4 treatment, while stem strength remained higher after anthesis as an adaptive response to mitigate lodging risk. Stem storage compounds can promote grain filling and a weight increase in inferior grains. The number of spikes per unit area increased significantly with increasing planting density, but the number of grains per spike and 1000-grain weight decreased significantly. In two years, the number of spikes in D3 treatment increased by a maximum of 211.67 × 104 ha−1 and 99.17 × 104 ha−1, respectively, compared to D1 and D2 treatments. The number of grains per spike was significantly higher than that of D4 treatment, the highest being 3.68 grains. Therefore, in the North China Plain with suitable water, fertilizer, and temperature, the sowing density of 270 × 104 plants/ha established population structure, significantly reduced CDMA, maintained post-anthesis stem strength, enhanced resilience of stems against post-anthesis lodging, and resulted in high yields by stabilizing the number of grains per spike and increasing the number of wheat spikes.