Abstract Flowering time and monocarpic senescence are tightly environmentally and genetically controlled. Typically, ‘early’ flowering and staygreen traits are associated with opposing life-history strategies; stress avoidance versus adaptation; with flowering time an overarching regulator of crop cycle length. We developed RIL populations segregating for Ppd-1 and NAM-1 variation, which are otherwise isogenic. Multi-year field experiments enabled exploration and uncoupling of the relationship between heading and staygreen traits. Heading date manipulation enabled introduction of staygreen traits to their target breeding environments, characterised by a ‘hot-finish’. Under moderate stress, we report a 2.9% and 1.9% increase in grain width ( P <0.0001), and 5.8% and 3.7% increase in TGW ( P <0.0001), plus significantly greater yield ( P <0.1) for ‘late’ heading staygreen RILs homozygous for NAM-A1, and NAM-D1 missense variants, respectively. Grain yield increases were proportionate to the delay in senescence, being greater for the NAM-A1 than the NAM-D1 variant. For RIL populations segregating for both traits, senescence variation was observed relative to heading-date. Regarding grain yield, the staygreen trait-associated increase in source size could not compensate for the Ppd-1a associated pleiotropic reduction in sink size, even under hypothesised continental target breeding environments, with trait competition identified. Therefore, to maximise the benefits associated with staygreen traits, especially in early-heading favouring environments required targeted manipulation of source-sink dynamics, and we propose multiple strategies. Highlight Staygreen traits were associated with extending grain fill duration, increasing grain width, TGW and grain yield. There appears an antagonist relationship between earlier heading and staygreen traits.

Abstract The semi dwarf stature of modern wheat varieties is conferred by RHT1 alleles derived from a single Japanese cultivar. These alleles are absent in landrace collections such as the Watkins collection. This constrains the direct use of rich genetic diversity preserved in Watkins landraces. These ancestral accessions, adapted to diverse local environments, harbour valuable traits absent from elite cultivars. Here, we demonstrate a precision breeding approach that integrates CRISPR/Cas9, cytosine base editing, and prime editing to introduce semi-dwarfing alleles into selected Watkins landraces. Our strategy overcomes problems caused by the tall stature of most Watkins accessions, providing rapid and precise modification of the Rht1 locus to confer semi-dwarf phenotypes. High editing efficiencies achieved across multiple Watkins landrace wheat lines confirm the robustness of our approach. By unlocking previously untapped genetic variation and enabling targeted trait integration, this study lays the foundation for modern landrace-based breeding programs, supporting sustainable wheat improvement and global food security.

Uniformity among seeds within a cultivar impacts seed quality and milling efficiency. Advances in hyperspectral imaging enable quantification of variability among individual seeds, facilitating treatment of seed heterogeneity as a heritable trait. We argue seed trait heterogeneity may be heritable and propose a roadmap to support breeding for uniform cultivars.

Grain quality in bread wheat is a complex trait determined by multiple genetic factors and their interaction with environmental conditions. This study investigated the genetic architecture of key grain quality traits in the Avalon & times; Cadenza double haploid (DH) population under contrasting climatic conditions in Kazakhstan. A set of 101 spring-type DH lines was evaluated over three years in three major wheat-growing regions of Kazakhstan, representing northern, central, and southern environments. Grain yield and nine grain quality traits were assessed, including amylose content (Amc, %), test weight per liter (TWL, g/L), grain protein content (GPC, %), gliadin content (Gli, %), glutenin content (Glu, %), grain hardness (GH, %), grain vitreousness (GV, %), falling number (FN, s), and sedimentation value determined in a 2% acetic acid solution (SV, mL). The objectives were to characterize phenotypic variation, examine trait relationships, and identify major and environmentally stable quantitative trait loci (QTLs) controlling grain quality. QTL mapping identified 89 QTLs associated with the nine studied traits, including 82 major QTLs explaining more than 10% of phenotypic variation and 16 stable QTLs detected in two or more environments. The largest numbers of QTLs were found for GPC, SV, and TWL. Stable QTLs were distributed across all three wheat genomes, with important regions detected on chromosomes 1A, 1B, 2D, 4A, 4D, 5A, 6A, and 7D. Several stable QTLs co-localized with genomic regions previously associated with grain quality and developmental regulation, including loci near Wx-B1, Rht-D1, and Ppd-D1, suggesting biologically meaningful links among gluten composition, starch biosynthesis, plant development, and grain physical properties. These results improve understanding of the genetic control of wheat grain quality across diverse environments in Kazakhstan and provide promising targets for marker-assisted selection to combine improved end-use quality with wide environmental adaptation.

Abstract Dietary fibre intake remains below recommended levels, and increasing fibre content of widely consumed white wheat flour (derived from the starchy endosperm) represents a scalable strategy to improve public health. In wheat starchy endosperm, arabinoxylan (AX) is the dominant fibre component, with the water-extractable (WE) fraction being particularly beneficial to health. We assembled an Elite Fibre Panel (EFP) of 384 elite modern wheat genotypes from UK commercial breeding programmes and quantified the content of WE-AX in wholemeal, as a proxy for soluble AX in white flour, across two UK field environments. Wholemeal WE-AX, showed substantial quantitative variation and moderate genotype-by-environment interaction, with a broad-sense heritability of 0.68. Genome-wide association analyses using 6,791 SNPs identified seven loci associated with WE-AX content. The strongest and most stable effects were mapped to major loci on chromosomes 1B and 6B, previously implicated in AX regulation, while additional loci of smaller and sometimes environment-dependent effect were detected on chromosomes 3A, 5B, and 7A. Favourable alleles increased WE-AX content by ∼5-15% and combined additively. LD-defined intervals contained several high-confidence candidate genes involved in cell-wall biosynthesis, remodelling and post-depositional modification, including PER1, a validated regulator of arabinoxylan cross-linking, together with genes encoding a UTP-glucose-1-phosphate uridylyltransferase, trichome birefringence-like proteins and xyloglucan endotransglucosylase/hydrolases. These findings demonstrate that substantial gains in soluble AX can be achieved by pyramiding favourable alleles already segregating within elite germplasm, providing a practical route for breeding wheat with enhanced dietary fibre content and improved nutritional quality. Key message Multiple additive loci controlling soluble arabinoxylan content were identified in elite wheat germplasm, enabling marker-assisted breeding for increased dietary fibre in white flour.

Wheat is a staple crop critical for global food security, and its continuous genetic improvement is essential to meet the demands of a growing population. Efficient, genotype-independent transformation is a major bottleneck in wheat functional genomics and gene editing. The growth regulating factor (GRF)-GRF-interacting factor (GIF) fusion technology enhances regeneration efficiency and broadens the range of transformable cultivars, but constitutive expression can reduce fertility and spikelet number. Here, we present an optimised Agrobacterium-mediated wheat transformation protocol incorporating GRF4-GIF1, tested across multiple tetraploid and hexaploid cultivars. Transformation efficiency was improved through adjustments in selection pressure, zeatin concentration, and promoter choice, with GRF4-GIF1 consistently enabling successful transformation across genotypes. Tissue-specific promoters and heat-inducible excision strategies effectively minimised pleiotropic effects, such as reduced fertility, while maintaining high transformation rates. This refined system provides a robust and versatile platform for gene function studies and gene editing, advancing genotype-independent wheat transformation and supporting breeding efforts to improve crop productivity, resilience, and nutritional value.

Increasing dietary fibre (DF) intake is an important target to improve health and an attractive strategy for this is to increase the fibre content of staple foods, particularly white bread which is the staple food in many countries. DF in wheat white flour is derived principally from the endosperm cell wall polysaccharide arabinoxylan (AX) and the water-extractable form of this (WE-AX) accounts for the majority of soluble dietary fibre (SDF), which is believed to confer particular health benefits. We previously identified QTLs for soluble dietary fibre (SDF) on 1B and 6B chromosomes in wheat in biparental populations. Here we show that the 6B high SDF allele encodes a peroxidase protein (PER1-v) with a single missense compared to the more common low SDF form (PER1). Wheat lines with the natural PER1-v allele and with an induced knock-out mutation in PER1 showed similar characteristics of reduced dimerization of ferulate associated with water-extractable WE-AX. Decreased ferulate dimerization is associated with decreased cross-linking of the WE-AX chains and increased solubility of AX. Transiently expressed PER1_RFP fusion driven by native promoter in wheat endosperm was shown to localise to cell walls whereas PER1-v_RFP did not; we therefore propose that PER1-v lacks capacity to dimerise AX ferulate in vivo due to mis-localisation. PER1 is the first peroxidase reported to be responsible for oxidative coupling of ferulate on AX, a key process in all grass cell walls. Understanding its role and the effect of variants on AX properties offers a route to control the properties of wheat DF in the human diet.

Abstract Future yield gains in wheat ( Triticum aestivum L.) will increasingly rely on multi‐omic approaches that combine phenomic and genomic data. In this study, we used canopy imaging to examine plant growth over time to assess plant growth dynamics and determine their relationship with grain yield and yield components. The doubled haploid spring wheat population (AAC Brandon/Pasteur) was phenotyped from 2021 to 2023 at Ottawa, Canada. High‐throughput image data were collected using the PlotCam, alongside manual measurements of yield components. These data were used to develop yield prediction models and quantitative trait locus (QTL) analysis using single nucleotide polymorphism‐based genotyping. Significant correlations were found between image‐derived traits, particularly estimated biomass (EBM), and both terminal dry biomass and grain yield. QTLs were associated with yield components, phenomic traits, and grain yield. Notably, a major grain yield QTL on chromosome 6D was linked to EBM from tillering through dough stages. A seed weight QTL on chromosome 2B was associated with senescence rate, while another on 6B co‐located with EBM at heading, flowering, and dough stages. Additionally, a QTL for spike and seed number on 5B was linked to EBM at emergence, heading, and dough stages. These results highlight the value of integrating image‐derived phenomics and genomic analysis to better understand the physiological basis of grain yield. This approach provides a deeper understanding of source–sink dynamics and offers a framework for selecting high‐performing genotypes across environments.

Modern crop breeding and seed certification agencies ignore the known spatial heterogeneity of soils and develop cultivars to thrive in a ‘one-size-fits-all’ soil environment. Neglecting the evolving dynamics of soils substantially undermines the capacity of new genotypes to deliver optimal yield and stress resilience, and requires urgent consideration in future plant breeding programmes.

Extending the duration of the stem elongation (SE) phase between terminal spikelet (TS) and anthesis has often been proposed as an avenue to increase wheat yield. However, accurate determination of TS is labour intensive, and existing evidence is often based on a limited number of genotypes observed under controlled conditions. Here, a Buster x Charger population comprising 108 doubled haploid lines was grown across four year-sites under UK field conditions. TS was recorded through meristem dissection and SE duration was measured as the time between TS and ear emergence (EE). Mixed model analysis across year-sites revealed high heritabilities (H2yield = 0.66, H2TS = 0.93, H2SE = 0.89, H2EE = 0.95) and strong genetic correlations between yield and the phenology traits SE and EE ( r g = 0.56 and r g = 0.6, respectively). While SE duration was mainly driven by EE, independent QTL for TS suggest that SE could be modified without affecting EE. The positive effect of SE duration on yield was attributed to increased grain number per area as well as increased grain weight, through independent QTL. Although validation in broader genetic backgrounds is needed, these QTL may offer opportunities for further yield increase in a physiological breeding framework. Highlights ### Competing Interest Statement The authors have declared no competing interest.

Bread wheat ( Triticum aestivum L.) plays a vital role in global food security, and its continuous genetic improvement is essential to meet the demands of a rapidly growing world population. Advances in genome sequencing and assembly have positioned wheat as a model crop for functional genomics and have increased the demand for highly efficient, genotype-independent transformation systems. A fusion technology involving a GROWTH-REGULATING FACTOR (GRF) and a GRF-INTERACTING FACTOR (GIF) has emerged as a powerful tool to enhance regeneration efficiency and expand the range of transformable genotypes. In this study, we present an optimized and robust Agrobacterium -mediated wheat transformation protocol incorporating GRF4-GIF1 , tested across multiple wheat varieties. Across all tested wheat cultivars, GRF4-GIF1 containing constructs consistently enabled successful transformation, with varied efficiencies depending on the genotype and promotors used to drive the gene fusion. Our method significantly improves transformation efficiency while minimizing GRF4-GIF1 pleiotropic effects, providing a versatile platform for gene function analysis and gene editing. This work represents a critical step toward efficient, genotype-independent transformation in wheat, supporting both research and breeding applications aimed at improving crop resilience, nutritional value, and productivity. ### Competing Interest Statement The authors have declared no competing interest. Biotechnology and Biological Sciences Research Council, BB/X011003/1 Scientific and Technological Research Council of Turkey

The coordination of floral developmental stages with the environment is important for reproductive success and optimization of crop yields. The timing of different developmental stages contributes to final yield potential, with optimal adaptation enabling development to proceed without being impacted by seasonal weather events, including frosts or end-of-season drought. Here, we characterize the role of FLOWERING LOCUS T3(FT3) in hexaploid bread wheat (Triticum aestivum) during the early stages of floral development. By assaying the genetic diversity of landraces and modern wheat varieties, we identified a distribution of alleles for FT3 that indicated selection in modern varieties. We generated transgenic overexpression lines and found that FT3 is as powerful a florigen as FT1, which suggested that FT3 is under tight regulation. To investigate this possibility, we measured FT3 expression under variable environmental conditions and identified a role for both temperature and photoperiod in FT3 regulation. Gene expression analysis showed that FT3 transcription is partly coordinated by a temperature-sensitive pathway consisting of a TEOSINTE BRANCHED 1-CYCLOIDEA-PROLIFERATING CELL FACTOR (TCP) transcription factor and a warm-temperature-responsive microRNA. We show that this regulation is important for the timing of floral development under short days combined with lower ambient temperatures and that there has been strong selection on FT3 during cultivation. Deploying this understanding to enable targeted combinations of alleles involved in adaptation will further our ability to develop climate-change-robust cultivars.

Grain protein content (GPC) is generally inversely correlated with grain yield (GY) but some genotypes consistently have higher or lower grain protein contents than predicted by simple regression analysis: this is called grain protein deviation (GPD). Positive GPD reflects greater nitrogen use efficiency and is an important target for breeders to develop more sustainable types of wheat. Here, we investigate the genetic architecture of GPC, GY, thousand grain weight (TGW) and GPD using a population of 104 doubled haploid lines derived from a cross between two cultivars with positive (Hereward) and negative (Malacca) GPD and grown in replicated randomised field trials over three years. A total of 9 QTL were detected for all traits, five for GPC, two for GPD and one each for GY and TGW. All of the increasing alleles for GPC and GPD and the single QTL for TGW were contributed by Hereward while Malacca contributed the single increasing allele for GY. The two QTLs for GPD located on chromosomes 3A and 5B explained 23.3% and 16.6% of the variance in the sample sets, respectively. Three QTL for GPC (on chromosomes 3A, 3B, 5B) each explained more than 14% of the variance, with those on chromosomes 3A and 5B having similar locations to the GPD QTLs on the same chromosomes. A survey of the gene content between the markers bordering the confidence intervals for the two GPD QTLs on chromosomes 3A and 5B identified 136 and 704 protein coding genes, respectively, including possible candidate genes.

Septoria tritici blotch (STB), caused by the Dothideomycete fungus Zymoseptoria tritici, is one of the most damaging diseases of bread wheat (Triticum aestivum)1 and the target of costly fungicide applications2. In line with the fungus's apoplastic lifestyle, STB resistance genes isolated to date encode receptor-like kinases (RLKs) including a wall-associated kinase (Stb6) and a cysteine-rich kinase (Stb16q)3,4. Here we used genome-wide association studies on a diverse panel of 300 whole-genome shotgun-sequenced wheat landraces (WatSeq consortium5) to identify a 99-kb region containing six candidates for the Stb15 resistance gene. Mutagenesis and transgenesis confirmed a gene encoding an intronless G-type lectin RLK as Stb15. The characterization of Stb15 exemplifies the unexpected diversity of RLKs conferring Z. tritici resistance in wheat.

Crop root traits that modulate the soil microbiome can turn the tide of reduced fertility in intensively farmed land by optimising nutrient availability and resilience to environmental stresses. Advantageous genetic diversity that allows adaptation to nutrient availability is present in historic crop genotypes. The Watkins collection of bread wheat landraces is an unexploited resource, carrying untapped phenotypic traits. Here, we show that the rhizosphere microbiome assembly of these landraces is distinct compared to elite varieties, specifically those that come from ancestral groups (AGs) not used in modern breeding. We used 16S rRNA sequencing to identify changes in microbial communities of rhizosphere soil collected from 81 landraces and two elite varieties. We found high similarity in microbiome recruitment between the elite cultivars and the two AGs genetically closest to the elite. The rhizosphere microbiome of five AGs genetically distant from the elite cultivars showed significant differences in the abundance of taxa involved in nitrogen and carbon turnover, keystone taxa and associations within the microbial network. Our findings suggest that genes to recruit or suppress microbial taxa in the rhizosphere are shared by landraces from these AGs. Selective breeding for traits to control microbial functions can enhance soil productivity and crop performance. ### Competing Interest Statement The authors have declared no competing interest. Biotechnology and Biological Sciences Research Council, BB/X003000/1, BB/X011003/1, BB/X011054/1, BBS/E/F/000PR13631, BB/X01097X/1, BB/X010996/1

High grain quality is a key target in wheat breeding and is influenced by genetic and environmental factors. This study evaluated 94 recombinant inbred lines (RILs) from a Pamyati Azieva × Paragon (PA × P) mapping population grown in two regions in Kazakhstan to assess the genetic basis of six grain quality traits: the test weight per liter (TWL, g/L), grain protein content (GPC, %), gluten content (GC, %), gluten deformation index in flour (GDI, unit), sedimentation value in a 2% acetic acid solution (SV, mL), and grain starch content (GSC, %). A correlation analysis revealed a trade-off between protein and starch accumulation and an inverse relationship between grain quality and yield components. Additionally, GPC exhibited a negative correlation with yield per square meter (YM2), underscoring the challenge of simultaneously improving grain quality and yield. With the use of the QTL Cartographer statistical package, 71 quantitative trait loci (QTLs) were identified for the six grain quality traits, including 20 QTLs showing stability across multiple environments. Notable stable QTLs were detected for GPC on chromosomes 4A, 5B, 6A, and 7B and for GC on chromosomes 1D and 6A, highlighting their potential for marker-assisted selection (MAS). A major QTL found on chromosome 1D (QGDI-PA × P.ipbb-1D.1, LOD 19.4) showed a strong association with gluten deformation index, emphasizing its importance in improving flour quality. A survey of published studies on QTL identification in common wheat suggested the likely novelty of 12 QTLs identified for GDI (five QTLs), TWL (three QTLs), SV, and GSC (two QTLs each). These findings underscore the need for balanced breeding strategies that optimize grain composition while maintaining high productivity. With the use of SNP markers associated with the identified QTLs for grain quality traits, the MAS approach can be implemented in wheat breeding programs.

The use of plant genetic resources (PGR)-wild relatives, landraces, and isolated breeding gene pools-has had substantial impacts on wheat breeding for resistance to biotic and abiotic stresses, while increasing nutritional value, end-use quality, and grain yield. In the Global South, post-Green Revolution genetic yield gains are generally achieved with minimal additional inputs. As a result, production has increased, and millions of hectares of natural ecosystems have been spared. Without PGR-derived disease resistance, fungicide use would have easily doubled, massively increasing selection pressure for fungicide resistance. It is estimated that in wheat, a billion liters of fungicide application have been avoided just since 2000. This review presents examples of successful use of PGR including the relentless battle against wheat rust epidemics/pandemics, defending against diseases that jump species barriers like blast, biofortification giving nutrient-dense varieties and the use of novel genetic variation for improving polygenic traits like climate resilience. Crop breeding genepools urgently need to be diversified to increase yields across a range of environments (>200 Mha globally), under less predictable weather and biotic stress pressure, while increasing input use efficiency. Given that the ~0.8 m PGR in wheat collections worldwide are relatively untapped and massive impacts of the tiny fraction studied, larger scale screenings and introgression promise solutions to emerging challenges, facilitated by advanced phenomic and genomic tools. The first translocations in wheat to modify rhizosphere microbiome interaction (reducing biological nitrification, reducing greenhouse gases, and increasing nitrogen use efficiency) is a landmark proof of concept. Phenomics and next-generation sequencing have already elucidated exotic haplotypes associated with biotic and complex abiotic traits now mainstreamed in breeding. Big data from decades of global yield trials can elucidate the benefits of PGR across environments. This kind of impact cannot be achieved without widescale sharing of germplasm and other breeding technologies through networks and public-private partnerships in a pre-competitive space.

This study evaluated 290 recombinant inbred lines (RILs) of the nested association mapping (NAM) population from the UK. The population derived from 24 families, where a common parent was “Paragon,” one of the UK’s spring wheat cultivar standards. All genotypes were tested in two regions of Kazakhstan at the Kazakh Research Institute of Agriculture and Plant Industry (KRIAPI, Almaty region, Southeast Kazakhstan, 2019–2022 years) and Alexandr Barayev Scientific-Production Center for Grain Farming (SPCGF, Shortandy, Akmola region, Northern Kazakhstan, 2019–2022 years). The studied traits consisted of plant adaptation-related traits, including heading date (HD, days), seed maturation date (SMD, days), plant height (PH, cm), and peduncle length (PL, cm). In addition, the yield per m2 was analyzed in both regions. Based on a field evaluation of the population in northern and southeastern Kazakhstan and using 10,448 polymorphic SNP (single-nucleotide polymorphism) markers, the genome-wide association study (GWAS) allowed for detecting 74 QTLs in four studied agronomic traits (HD, SMD, PH, and PL). The literature survey suggested that 16 of the 74 QTLs identified in our study had also been detected in previous QTL mapping studies and GWASs for all studied traits. The results will be used for further studies related to the adaptation and productivity of wheat in breeding projects for higher grain productivity.

Harnessing genetic diversity in major staple crops through the development of new breeding capabilities is essential to ensure food security1. Here we examined the genetic and phenotypic diversity of the A. E. Watkins landrace collection2 of bread wheat (Triticum aestivum), a major global cereal, by whole-genome re-sequencing of 827 Watkins landraces and 208 modern cultivars and in-depth field evaluation spanning a decade. We found that modern cultivars are derived from two of the seven ancestral groups of wheat and maintain very long-range haplotype integrity. The remaining five groups represent untapped genetic sources, providing access to landrace-specific alleles and haplotypes for breeding. Linkage disequilibrium-based haplotypes and association genetics analyses link Watkins genomes to the thousands of identified high-resolution quantitative trait loci and significant marker-trait associations. Using these structured germplasm, genotyping and informatics resources, we revealed many Watkins-unique beneficial haplotypes that can confer superior traits in modern wheat. Furthermore, we assessed the phenotypic effects of 44,338 Watkins-unique haplotypes, introgressed from 143 prioritized quantitative trait loci in the context of modern cultivars, bridging the gap between landrace diversity and current breeding. This study establishes a framework for systematically utilizing genetic diversity in crop improvement to achieve sustainable food security.

Wheat is an important source of minerals for human nutrition and increasing grain mineral content can contribute to reducing mineral deficiencies. Here, we identify QTLs for mineral micronutrients in grain of wheat by determining the contents of six minerals in a total of eleven sample sets of three biparental populations from crosses between A.E. Watkins landraces and cv. Paragon. Twenty-three of the QTLs are mapped in two or more sample sets, with LOD scores above five in at least one set with the increasing alleles for sixteen of the QTLs being present in the landraces and seven in Paragon. Of these QTLs, the number for each mineral varies between three and five and they are located on 14 of the 21 chromosomes, with clusters on chromosomes 5A (four), 6A (three), and 7A (three). The gene content within 5 megabases of DNA on either side of the marker for the QTL with the highest LOD score is determined and the gene responsible for the strongest QTL (chromosome 5A for Ca) identified as an ATPase transporter gene (TraesCS5A02G543300) using mutagenesis. The identification of these QTLs, together with associated SNP markers and candidate genes, will facilitate the improvement of grain nutritional quality. Landraces collected 100 years ago have been used to identify novel QTLs and candidate genes for essential mineral micronutrients in wheat, demonstrating the potential of exploiting diversity in older genotypes.