Nitrogen use efficiency (NUE) is a key determinant of sustainable wheat production, yet its genetic basis remains incompletely understood under variable nitrogen supply. Grain yield and quality traits exhibit distinct responses to different nitrogen dosages, and the genetic loci and core genes governing low-nitrogen adaptability have not been systematically dissected via multi-omics integration. We evaluated 191 wheat accessions under four nitrogen application rates (N0, N150, N210, N270) across two environments and implemented an integrated framework combining multi-model GWAS, LD-based locus consolidation, RNA-seq, and WGCNA analyses to identify candidate genes. Phenotypic analysis revealed strong trait-specific nitrogen responses, with spike number (SN), grain number per spike (GNS), and plant height (PH) peaking at N210, while thousand grain weight (TGW) declined and grain protein content (GPC) increased with increasing nitrogen. Based on TGW, SN, and GNS, adaptability scores and low-nitrogen tolerance indices were constructed to classify genotypes into four performance groups, identifying 41 accessions (21.5

[Objective]The flour color is a crucial index for evaluating wheat quality.Identifying superior allelic variations at loci associated with flour color and clarifying their breeding utilization effects will provide a foundation for molecular marker-assisted breeding of wheat flour color.[Method]Using functional markers,molecular detection was conducted on 12 flour color-related loci in 166 wheat varieties(lines),including the Psy-A1,Pds-B1,Lcye-A1,Lcye-B1,Lox-B1,Ppo-A1,Ppo-B1,Ppo-D1,Pod-A1,Pod-D1,Pod-2D genes,and the 1B/1R translocation.Combined with the phenotypic measurements of flour color parameters(Yellow pigment content(YPC),L* value,a* value,b* value and whiteness),the influence of different allelic variations on flour color were analyzed to comprehensively and systematically evaluate the breeding utilization effects of each locus.[Result]The flour color of the tested materials exhibited a wide variation range.The average value of YPC was 1.18 μg·g-1,with a range of 0.57-2.96 μg·g-1;The average value of L* was 90.29,ranging from 87.12 to 92.16;the average a* value was-0.86,varying between-1.78 and-0.09;the average b* value was 8.83,with a range of 5.21-14.69;and the average whiteness was 86.78,spanning from 81.35 to 90.30.Environment,genotype,and the interaction between genotype and environment all significantly influenced flour color,with genotype exerting the strongest effect on the phenotypic variations.Psy-A1 and 1B/1R translocation significantly affected YPC,L* value,a* value,b* value and whiteness;Lcye-B1 significantly influenced YPC,a* value,b* value and whiteness;Pds-B1 and Lox-B1 significantly impacted L* value,b* value and whiteness;Pod-2D significantly influenced L*value and whiteness;Lcye-A1 significantly affected L* value;Ppo-A1 and Ppo-D1 significantly influenced a* value.These nine loci had substantial impacts on flour color and exhibited great potential for breeding applications.Wheat varieties(lines)containing Psy-A1b,Pds-B1b,Lcye-A1b,Lcye-B1b,Lox-B1a,Ppo-A1b,Ppo-D1a,Pod-2D-GG,Pod-2D-AG and non-1B/1R translocation exhibited high brightness and whiteness flour color.These genotypes were designated as superior alleles,with distribution frequencies of 34.94%,20.48%,97.59%,66.27%,26.38%,50.91%,57.23%,48.80%,15.06%and 51.20%,respectively.As the number of superior alleles increased,the L* value,a* value and whiteness gradually increased,while YPC and b* value gradually decreased.The materials pyramiding 7-8 superior genes exhibited the optimal flour color.There were significant differences in flour color and the allelic variation frequencies of related genes among wheat varieties(lines)from different regions.A total of 22 varieties,such as Zhengyin1,Zimai12 and Wanmai19,carried more than seven superior alleles and could be used as parental materials for breeding wheat varieties with high brightness and whiteness flour.[Conclusion]Psy-A1,Pds-B1,Lcye-A1,Lcye-B1,Lox-B1,Ppo-A1,Ppo-D1,Pod-2D and 1B/1R translocation significantly influence flour color and exhibit strong breeding practicability.Twenty-two wheat varieties,such as Zhengyin1,Zimai12 and Wanmai19,can be used as excellent parents for flour color improvement.

[This corrects the article DOI: 10.3389/fpls.2024.1457437.].

Apart from starch content, structure is also vital for the eating and nutritional qualities of final products. The study investigated how the starch structure changed during grain filling period using two wheat cultivars with different filling rate. The starch biosynthesis during grain filling was not at uniform speed and most of starches were synthesized before 19 DAF. The starch structure establishment was latter than starch accumulation, but the structure formed at early stage of grain filling was highly related to the final one. The process of starch biosynthesis was closely accompanied by the elongation of amylose chains, increase on branch numbers, B-type granule number and expansion of A-type granule. Further analysis on expression profiles of key genes involved in starch biosynthesis demonstrated that different genes exhibited varying responsiveness to the filling rate, and the resulting imbalance in gene expression may underlie the observed structural differences. Faster filling promoted earlier activation of starch-biosynthesis genes, particularly GBSSI, leading to preferential elongation of amylose chains, higher crystallinity, and more B-type granules. The results will provide new insights to understanding the formation starch structure during grain filling, which may benefit future research on management and breeding.

Male-sterile genes and mutants are critical for hybrid seed production in monocotyledonous crops. Lipids are essential structural components of male reproductive organs, such as the anther and pollen. Here, we show that the pollen-preferential gene TaRIP2 is essential for wheat anther development and pollen formation. RT-qPCR analysis revealed TaRIP2 is specifically expressed during the callose and tetrad stages. Using CRISPR/Cas9, we generated TaRIP2 mutants (rip2), which displayed smaller, wilted anthers with defective cuticles and a low proportion of viable pollen grains (~5.7%). Microscopy revealed that the mutant Rip2 microspores had a smaller size, a smooth exine lacking sculptural elements and fewer organelles. RNA-seq identified differentially expressed genes (DEGs) enriched in pathways related to pollen wall formation. KEGG analysis showed these DEGs are involved in cutin, suberine and wax biosynthesis and fatty acid degradation. Fatty acids C16:0, C18:0 and C18:2 were significantly elevated in rip2 anthers. These phenotypes coincided with the downregulation of genes involved in lipid metabolism and anther development. Dual-luciferase and EMSA assays confirmed TaRIP2 is directly regulated by the transcription factor MYB80. Together, our results show TaRIP2 regulates pollen wall formation through the MYB80-control lipid metabolic pathways.

Introduction:Powdery mildew (PM) poses an extreme threat to wheat yields and quality.[Methods] In this study, 262 recombinant inbred lines (RILs) of Doumai and Shi 4185 cross were used to map PM resistance genes across four environments. A high-density genetic linkage map of the Doumai/Shi 4185 RIL population was constructed using the wheat Illumina iSelect 90K single-nucleotide polymorphism (SNP) array. Results:In total, four stable quantitative trait loci (QTLs) for PM resistance, QPm.caas-2AS, QPm.caas-4AS, QPm.caas-4BL, and QPm.caas-6BS, were detected and explained 5.6%-15.6% of the phenotypic variances. Doumai contributed all the resistance alleles of QPm.caas-2AS, QPm.caas-4AS, QPm.ca as-4BL, and QPm.caas-6BS. Among these, QPm.caas-4AS and QPm.caas-6BS overlapped with the previously reported loci, whereas QPm.caas-2AS and QPm.caas-4BL are potentially novel. Additionally, six high-confidence genes encoding the NBS-LRR-like resistance protein, disease resistance protein family, and calcium/calmodulin-dependent serine/threonine-kinase were selected as the candidate genes for PM resistance. Three kompetitive allele-specific PCR (KASP) markers, Kasp_PMR_2AS for QPm.caas-2AS, Kasp_PMR_4BL for QPm.caas-4BL, and Kasp_PMR_6BS for QPm.caas-6BS, were developed, and their genetic effects were validated in a natural population including 100 cultivars. Discussion:These findings will offer valuable QTLs and available KASP markers to enhance wheat marker-assisted breeding for PM resistance.

Wheat variety Jimai0435 is recently released with high quality. It has excellent quality characteristics, especially the quality of steamed bread. In order to explore the optimal processing conditions for its steamed bread, its quality characteristics were introduced firstly, and then the effects of the fermentation time and pressing times on the steamed bread quality were focused. And the effects of fermentation time and pressing times on the quality of its steamed bread were mainly studied in laboratory. The analysis of difference significance showed that the steamed bread quality was most affected by the fermentation time before pressing, followed by the pressing times, the internal quality was affected by the fermentation time and pressing times. Based on the multiple comparison and graphic analysis of the external and internal qualities, it was found that with the prolong of fermentation time, the pressing times needed to be correspondingly increased in order to make good quality steamed bread, and the proper pressing times is 15 when the dough is fermented for 20 min, while 20 times was needed when the fermentation time is prolonged to 25-30 min.

The identification of stable quantitative trait locus (QTL) for yield-related traits and tightly linked molecular markers is important for improving wheat grain yield. In the present study, six yield-related traits in a recombinant inbred line (RIL) population derived from the Zhongmai 578/Jimai 22 cross were phenotyped in five environments. The parents and 262 RILs were genotyped using the wheat 50K single nucleotide polymorphism (SNP) array. A high-density genetic map was constructed with 1 501 non-redundant bin markers, spanning 2 384.95 cM. Fifty-three QTLs for six yield-related traits were mapped on chromosomes 1D (2), 2A (9), 2B (6), 2D, 3A (2), 3B (2), 4A (5), 4D, 5B (8), 5D (2), 7A (7), 7B (3) and 7D (5), which explained 2.7-25.5% of the phenotypic variances. Among the 53 QTLs, 23 were detected in at least three environments, including seven for thousand-kernel weight (TKW), four for kernel length (KL), four for kernel width (KW), three for average grain filling rate (GFR), one for kernel number per spike (KNS) and four for plant height (PH). The stable QTLs QKl.caas-2A.1, QKl.caas-7D, QKw.caas-7D, QGfr.caas-2B.1, QGfr.caas-4A, QGfr.caas-7A and QPh. caas-2A.1 are likely to be new loci. Six QTL-rich regions on 2A, 2B, 4A, 5B, 7A and 7D, showed pleiotropic effects on various yield traits. TaSus2-2B and WAPO-A1 are potential candidate genes for the pleiotropic regions on 2B and 7A, respectively. The pleiotropic QTL on 7D for TKW, KL, KW and PH was verified in a natural population. The results of this study enrich our knowledge of the genetic basis underlying yield-related traits and provide molecular markers for high-yield wheat breeding.

We identified a new wheat dwarfing allele Rht12b conferring reduced height and higher grain yield, pinpointed its causal variations, developed a breeding-applicable marker, and traced its origin and worldwide distribution. Plant height control is essential to optimize lodging resistance and yield gain in crops. RHT12 is a reduced height (Rht) locus that is identified in a mutationally induced dwarfing mutant and encodes a gibberellin 2-oxidase TaGA2oxA13. However, the artificial dwarfing allele is not used in wheat breeding due to excessive height reduction. Here, we confirmed a stable Rht locus, overlapping with RHT12, in a panel of wheat cultivars and its dwarfing allele reduced plant height by 5.4–8.2 cm, equivalent to Rht12b, a new allele of RHT12. We validated the effect of Rht12b on plant height in a bi-parent mapping population. Importantly, wheat cultivars carrying Rht12b had higher grain yield than those with the contrasting Rht12a allele. Rht12b conferred higher expression level of TaGA2oxA13. Transient activation assays defined SNP−390(C/A) in the promoter of TaGA2oxA13 as the causal variation. An efficient kompetitive allele-specific PCR marker was developed to diagnose Rht12b. Conjoint analysis showed that Rht12b plus the widely used Rht-D1b, Rht8 and Rht24b was the predominant Rht combination and conferred a moderate plant height in tested wheat cultivars. Evolutionary tracking uncovered that RHT12 locus arose from a tandem duplication event with Rht12b firstly appearing in wild emmer. The frequency of Rht12b was approximately 70

High-molecular-weight glutenin subunits (HMW-GS), a major component of seed storage proteins (SSP) in wheat, largely determine processing quality. HMW-GS encoded by GLU-1 loci are mainly controlled at the transcriptional level by interactions between cis-elements and transcription factors (TFs). We previously identified a conserved cis-regulatory module CCRM1-1 as the most essential cis-element for Glu-1 endosperm-specific high expression. However, the TFs targeting CCRM1-1 remained unknown. Here, we built the first DNA pull-down plus liquid chromatography-mass spectrometry platform in wheat and identified 31 TFs interacting with CCRM1-1. TaB3-2A1 as proof of concept was confirmed to bind to CCRM1-1 by yeast one hybrid and electrophoretic mobility shift assays. Transactivation experiments demonstrated that TaB3-2A1 repressed CCRM1-1-driven transcription activity. TaB3-2A1 overexpression significantly reduced HMW-GS and other SSP, but enhanced starch content. Transcriptome analyses confirmed that enhanced expression of TaB3-2A1 down-regulated SSP genes and up-regulated starch synthesis-related genes, such as TaAGPL3, TaAGPS2, TaGBSSI, TaSUS1 and TaSUS5, suggesting that it is an integrator modulating the balance of carbon and nitrogen metabolism. TaB3-2A1 also had significant effects on agronomic traits, including heading date, plant height and grain weight. We identified two major haplotypes of TaB3-2A1 and found that TaB3-2A1-Hap1 conferred lower seed protein content, but higher starch content, plant height and grain weight than TaB3-2A1-Hap2 and was subjected to positive selection in a panel of elite wheat cultivars. These findings provide a high-efficiency tool to detect TFs binding to targeted promoters, considerable gene resources for dissecting regulatory mechanisms underlying Glu-1 expression, and a useful gene for wheat improvement.

We fine mapped RHT26 for plant height in wheat, confirmed its genetic effects in a panel of wheat cultivars and predicted candidate genes. Development of wheat cultivars with appropriate plant height (PH) is an important goal in breeding. Utilization of semi-dwarfing genes Rht-B1b and Rht-D1b triggered wheat Green Resolution in the 1960s. Since these genes also bring unfavorable features, such as reduced coleoptile length and grain weight, it is necessary to identify alternative reduced height genes without yield penalty. Here we constructed a high-density genetic map of a recombinant inbred line population derived from the cross of Zhongmai175 and Lunxuan987 and detected a stable genetic locus for PH, designated RHT26, on chromosome arm 3DL in all of six environments, accounting for 6.8–14.0

We fine mapped QTL QTKW.caas-5DL for thousand kernel weight in wheat, predicted candidate genes and developed a breeding-applicable marker. Thousand kernel weight (TKW) is an important yield component trait in wheat, and identification of the underlying genetic loci is helpful for yield improvement. We previously identified a stable quantitative trait locus (QTL) QTKW.caas-5DL for TKW in a Doumai/Shi4185 recombinant inbred line (RIL) population. Here we performed fine mapping of QTKW.caas-5DL using secondary populations derived from 15 heterozygous recombinants and delimited the QTL to an approximate 3.9 Mb physical interval from 409.9 to 413.8 Mb according to the Chinese Spring (CS) reference genome. Analysis of genomic synteny showed that annotated genes in the physical interval had high collinearity among CS and eight other wheat genomes. Seven genes with sequence variation and/or differential expression between parents were predicted as candidates for QTKW.caas-5DL based on whole-genome resequencing and transcriptome assays. A kompetitive allele-specific PCR (KASP) marker for QTKW.caas-5DL was developed, and genotyping confirmed a significant association with TKW but not with other yield component traits in a panel of elite wheat cultivars. The superior allele of QTKW.caas-5DL was frequent in a panel of cultivars, suggesting that it had undergone positive selection. These findings not only lay a foundation for map-based cloning of QTKW.caas-5DL but also provide an efficient tool for marker-assisted selection.

Rht-B1b and Rht-D1b, the 'Green Revolution' (GR) genes, greatly improved yield potential of wheat under nitrogen fertilizer application, but reduced coleoptile length, seedling vigor and grain weight. Thus, mining alternative reduced plant height genes without adverse effects is urgently needed. We isolated the causal gene of Rht24 through map-based cloning and characterized its function using transgenic, physiobiochemical and transcriptome assays. We confirmed genetic effects of the dwarfing allele Rht24b with an association analysis and also traced its origin and distribution. Rht24 encodes a gibberellin (GA) 2-oxidase, TaGA2ox-A9. Rht24b conferred higher expression of TaGA2ox-A9 in stems, leading to a reduction of bioactive GA in stems but an elevation in leaves at the jointing stage. Strikingly, Rht24b reduced plant height, but had no yield penalty; it significantly increased nitrogen use efficiency, photosynthetic rate and the expression of related genes. Evolutionary analysis demonstrated that Rht24b first appeared in wild emmer and was detected in more than half of wild emmer and wheat accessions, suggesting that it underwent both natural and artificial selection. These findings uncover an important genetic resource for wheat breeding and also provide clues for dissecting the regulatory mechanisms underlying GA-mediated morphogenesis and yield formation.

茎基腐病(Fusarium crown rot,FCR)已成为影响我国小麦生产的主要病害之一,发掘抗病基因和种质可为解析其抗病遗传机制和聚合育种提供指导.本研究选用藁城8901/周麦16构建的重组自交系(recom-binant inbred line,RIL)群体为材料,基于已构建的90K SNP高密度遗传连锁图谱,对接菌条件下苗期FCR抗性进行QTL(quantitative trait loci)定位.结果表明,RIL群体苗期FCR病情指数在基因型和不同试验间均达显著差异(P<0.01).藁城8901表现为感FCR,周麦16表现为高感FCR,家系表现为连续变异和超亲分离.在3次试验及均值中共定位到14个与苗期FCR抗性显著相关的QTL,分布在1D(2)、3B(2)、4A(2)、5B(2)、5D、6A(4)和7B染色体上,解释表型变异的4.42％～11.37％;其中,4个在两次试验中均被检测到.本研究表明感病和高感亲本也可用于抗病品种的培育和基因发掘,检测到的4个稳定QTL和抗病家系为FCR抗病育种提供了可用的资源.

Waxy wheat variety Jinuo116 is one novel type for its special starch properties bred by Crop Research Institute of SAAS (Shandong Academy of Agricultural Sciences) and released by Shandong Province. In order to fully interpret the improvement effect of waxy cultivar Jinuo116, the main food such as dry noodles, quick-frozen noodles and steamed bread were prepared by mixing Jinuo116 flour with different fine flour and whole meal flour, and its improving adaptability was conducted. The quality stability of Jinuo116 planted in six ecological zones had been analyzed firstly, the variable coefficient of grain hardness and protein content were lower 5.0%, wet gluten content was 10.82%. For starch pasting properties, the variable coefficient of peak time was only 1.51%, other pasting properties were all lower 7.59%. For dough properties, the variable coefficient of water absorption was very low (only 0.68%), while that of stability time, weakness and Farinograph Quality Index were 22.82%, 12.80% and 17.95%, respectively. These showed that Jinuo116 had stable grain characteristics, dough rheological properties and starch gelatinization. Then the quality of noodles and steamed bread of mixing flour was identified by blending Jinuo116 flour into non-waxy wheat flour such as Jimai22, Jimai229, Jimai44 and Jizimai1, and showed that Jinuo116 flour could greatly improve the viscoelasticity and smoothness of dry noodles and quick-frozen noodles, and the appending proportions were changed based on the different gluten strength of non-waxy varieties, and the range of blending ratio was from 20% to 40%. While considering the integrated qualities of noodles, the appropriate ratio should be controlled at about 30%. Quality characteristics such as hardness, viscoelasticity, smoothness of noodles made of purple whole meal flour had been improved obviously, and the noodles had better taste quality, so the suitable proportion of flour blending was 20%. The internal structure, toughness and viscosity of steamed bread made of purple whole meal flour were improved markedly, and the best internal quality characteristics were got when the adding proportion was 20%. For its good quality properties especially the outstanding starch characteristics, Jinuo116 flour could be used as blending flour to improve the food quality made of non-waxy wheat.

Wheat pathogens, especially those causing powdery mildew and stripe rust, seriously threaten yield worldwide. Utilizing newly identified disease resistance genes from wheat relatives is an effective strategy to minimize disease damage. In this study, chromosome-specific molecular markers for the 3Sb and 7Sb chromosomes of Aegilops bicornis were developed using PCR-based landmark unique gene primers for screening wheat-A. bicornis progenies. Fluorescence in situ hybridization (FISH) was performed to further identify wheat-A. bicornis progenies using oligonucleotides probes Oligo-pSc119.2-1, Oligo-pTa535-1, and Oligo-(GAA)8. After establishing A. bicornis 3Sb and 7Sb chromosome-specific FISH markers, Holdfast (common wheat)-A. bicornis 3Sb addition, 7Sb addition, 3Sb(3A) substitution, 3Sb(3B) substitution, 3Sb(3D) substitution, 7Sb(7A) substitution, and 7Sb(7B) substitution lines were identified by the molecular and cytological markers. Stripe rust and powdery mildew resistance, along with agronomic traits, were investigated to evaluate the breeding potential of these lines. Holdfast and Holdfast-A. bicornis progenies were all highly resistant to stripe rust, indicating that the stripe rust resistance might derive from Holdfast. However, Holdfast-A. bicornis 3Sb addition, 3Sb(3A) substitution, 3Sb(3B) substitution, and 3Sb(3D) substitution lines showed high resistance to powdery mildew while Holdfast was highly susceptible, indicating that chromosome 3Sb of A. bicornis carries previously unknown powdery mildew resistance gene(s). Additionally, the transfer of the 3Sb chromosome from A. bicornis to wheat significantly increased tiller number, but chromosome 7Sb has a negative effect on agronomic traits. Therefore, wheat germplasm containing A. bicornis chromosome 3Sb has potential to contribute to improving powdery mildew resistance and tiller number during wheat breeding.

为了培育高产稳产、抗旱节水、多抗广适的突破性小麦品种,以高产品种'临麦2号'为母本,以高产抗旱品种'烟农19'为父本,采用系谱法聚合二者优异农艺性状,通过多点多生态鉴定与评价,育成小麦新品种'济麦262'.该品种产量高,品质优良,抗病抗逆性好,农艺性状优异,水旱兼用.在2010—2011年度济南和蒙阴水浇地品比试验中,平均产量较对照'济麦22'增产2.87％和9.41％,均居第一位;在2012—2013年度山东省旱地区域试验中,平均产量较对照'鲁麦21'增产9.74％,是近10年来增产幅度最大的旱地小麦.该品种籽大饱满,籽粒蛋白质含量、湿面筋含量和面粉白度等品质指标优于对照品种'鲁麦21';抗干热风,中抗条锈病;株高67.2 cm,后期叶片功能期长,落黄佳,长方形穗,穗粒数37.5粒,千粒重44.7 g,白粒,粉质.'济麦262'于2016年2通过山东省审定,适宜在无浇灌条件的旱肥地及水资源匮乏地区种植应用.

Among yield contributing traits, the contribution of canopy activity related traits has been less studied. In this study, quantitative trait loci (QTL) for the normalized difference vegetation index (NDVI) at the seedling (NDVI-S) and grain filling (NDVI-10) stages and the chlorophyll (Chl) content at the grain filling stage (Chl-10) were mapped using three recombinant inbred line (RIL) populations of wheat derived from the following crosses: Doumai × Shi 4185 (D × S), Gaocheng 8901 × Zhoumai 16 (G × Z) and Linmai 2 × Zhong 892 (L × Z). In the three RIL populations, 6, 16 and 14 QTL were identified for NDVI-S, NDVI-10 and Chl-10, respectively. Furthermore, 6, 10 and 10 of the QTL were newly detected. Three QTL QNDVI-10.caas-4BS, QNDVI-10.caas-4DS and QChl-10.caas-4BS, were commonly detected in two populations. Twelve QTL clusters for both canopy activity related traits in the present study and grain yield (GY) related traits in our previous study were identified. NDVI-S is phenotypically and genetically correlated with thousand-kernel weight (TKW), which can be used to select lines with a high TKW. The QTL clusters harbouring QTL for canopy activity related traits and GY related traits are valuable in marker-assisted selection (MAS) of loci with pleiotropic effects. In addition, the stable QTL QNDVI-S.caas-1AL and QNDVI-10.caas-3B can be used to identify high NDVI lines at the seedling and grain filling stages, respectively. Our study provided new insight into the genetic architecture of the GY based on canopy activity related traits.