Search Results (109)

Aegilops geniculata Roth is a tetraploid wild relative of wheat distributed throughout the Mediterranean Basin, where it grows in a wide range of habitats. Due to its genetic diversity, ecological plasticity and adaptation to Mediterranean ruderal environments, the species has attracted increasing interest as a genetic resource for wheat improvement and as a potential component of sustainable agroecosystems. Beyond use in agriculture, its ecological characteristics also suggest applications in Nature-based Solutions, including revegetation of degraded, low-input, semi-arid ecosystems. This review aims to provide a comprehensive synthesis of current knowledge on the taxonomy, genetics, morphology, distribution, ecology, reproductive biology and conservation of Ae. geniculata. This work is complemented by original experimental data on agronomic traits and an assessment of ex situ conservation efforts. Evidence highlights the species’ value as a source of drought- and stress-adaptive traits for wheat improvement, plus promising cover crop traits (rapid establishment, stable biomass production and flexible germination behavior). Remaining knowledge gaps include population genomics, conservation of undercollected populations and field-scale agronomic performance to better clarify the potential of this species as a cover crop. This work supports further investigation of Ae. geniculata as both a valuable crop wild relative and a promising cover crop for Mediterranean agroecosystems. Full article

Cannabis sativa is a multi-use crop with applications in food, fiber, construction, and medicinal industries. Cannabis plants with low Δ9-tetrahydrocannabinol (THC) concentrations (industrial hemp) have recently been legalized for industrial cultivation by multiple nations across the globe. This crop has been traditionally ignored and lags behind established crops like wheat, corn, and cotton in breeding and the development of novel traits. We employed chemical mutagenesis to develop novel traits in industrial hemp (Cannabis sativa L.). We used ethyl methanesulfonate (EMS) as the chemical mutagen and determined the lethal dose (LD50) to be 2% (v/v) for 5 h for the heat-tolerant (HT) (diploid, 2n) accession and 2% (v/v) for 8 h for the 4x (tetraploid, 2n = 4x = 40) accession. The variations in seed germination percentages among mutagen treatments were found to be highly significant (p < 0.05). The parental generation (M0) seeds were treated with the LD50 dosage of the mutagen to produce mutant M1 populations. The first mutant generation (M1) and second mutant generation (M2) plants displayed a wide array of phenotypes such as dwarf plants, twin seedlings, leaf variegation, fasciation, purple anthocyanins, hard/leathery leaf texture, trifoliate leaves, bushy stature, and unusual leaf shape, which is a testament to the effectiveness and accuracy of the LD50 dosage calibration results. Full article

Tetraploid wheat (Triticum turgidum), the progenitor of common wheat, provides rich genetic resources for wheat genetic improvement. TDI-1 is a long-grain cultivated emmer wheat (T. turgidum ssp. dicoccum) accession collected in our laboratory. It was crossed with TDU-1, a short-grain durum wheat (T. turgidum ssp. durum) accession. The F₁ hybrids exhibited heterobeltiosis (i.e., performance superior to the better parent) for grain length, thousand-kernel weight, and other kernel traits. In the F₂ population, grain length showed a strong positive correlation with thousand-kernel weight (r = 0.77), and the ratio of plants with the short-grain parental phenotype, heterobeltiosis phenotype, and long-grain parental phenotype was approximately 1:2:1 (χ² ≈ 0.697, p > 0.7), suggesting that a major locus plays a primary role in controlling grain length in this population. Combined with phenotyping of F_2:3 families, homozygous long-grain and short-grain bulks constructed from F₂ individuals were genotyped using bulked segregant analysis based on 120K-SNP array. The results showed that polymorphic SNPs were mainly concentrated on the short arm of chromosome 2A, leading to the inference that this region harbors a locus regulating grain length, tentatively designated TtGL-2A. Twelve SSR markers were developed on the short arm of chromosome 2A, mapping TtGL-2A to an 8.1 cM genetic interval between markers 2AS-280t26 and 2AS-280t29, corresponding to the physical interval 121.2–158.8 Mb, with a LOD score of 12.3. Using the diagnostic marker 2AS-95t3 to genotype 253 wheat accessions, the proportion of long-grain allelic variation TtGL-2A_TDI in landraces, cultivars, and introduced lines is 40.27%, 75.86%, and 82.35%, respectively. Transcriptome sequencing of grains at 15 days post-anthesis from the parental lines TDI-1 and TDU-1 identified 11 differentially expressed genes within the TtGL-2A interval. These results lay a foundation for map-based cloning of TtGL-2A and provide an efficient marker for molecular breeding of wheat yield. Full article

Starch synthesis is critical for crop yield and quality and is regulated and coordinated by a series of key enzymes encoded by starch synthesis-related genes (SSRGs). Although this process is well characterized in many crops, the genomic location and expression patterns of SSRGs in wheat remain unclear. Here, we performed a genome-wide analysis and identified 78 SSRGs in wheat, classified into the AGPase, SSS, GBSS, SBE, and DBE subfamilies. SSRGs within each subfamily showed conserved motifs and domain organization. RNA-seq analysis indicated that most SSRGs are expressed during early grain development. We further examined genetic variation in SSRGs across wheat and its progenitors using re-sequencing data. Diploid wheat showed greater genetic differentiation and diversity than tetraploid and hexaploid wheat. Five SSRGs exhibited significant haplotype differences between emmer wheat and common wheat; emmer wheat displayed diverse haplotypes, whereas common wheat showed a single dominant haplotype. Finally, starch characteristics differed between emmer wheat and common wheat in amylose content and thermodynamic properties, while viscosity, crystal structure, and morphology were largely similar. Overall, this study systematically characterizes SSRGs in wheat and provides insights for improving starch quality. Full article

Gluten allergy is linked to high risk of anaphylaxis. The relative allergenicity of glutens (alcohol-soluble gliadin and acid-soluble glutenin) from the three commercially grown wheat species (diploid Triticum monococcum, tetraploid Triticum durum, hexaploid Triticum aestivum) is unknown. A comparative gluten allergenicity map (CGAM) from these species will enable the identification of potentially hyper-/hypo-/iso-allergenic species/varieties of wheat as well as the determination of substantial equivalence of genetically engineered (GE) or other novel wheat lines. Here, using a recently described novel mouse model, we tested the hypothesis that the three different wheat species will exhibit natural variation in their gluten allergenicity. Groups of Balb/c mice were transdermally sensitized to alcohol-soluble or acid-soluble gluten extracts followed by elicitation of systemic anaphylaxis. Initial studies were performed to validate the model for glutens from the three wheat species. Both glutens from all three wheat species elicited robust specific IgE responses, as well as systemic anaphylaxis. However, comparative mapping analysis revealed differences in capacity to elicit specific IgE among the three wheat species with T. aestivum being the most potent in both gluten extracts. Hypothermic shock response analysis revealed that the three species elicited similar kinetics and intensity of anaphylaxis. Nevertheless, when analyzing mucosal mast cell response, it was revealed that the glutens from T. aestivum emerged as the most potent elicitor. Collectively, these results yield the first CGAM that may be utilized for preclinical testing of the allergenic potential of glutens from novel (e.g., GE) wheats and processed wheat products against existing wheat glutens. Full article

Globally, 5.94 million accessions are conserved across 867 genebanks, of which 41.5% (2.47 million) are cereal crop accessions. Only a small portion of global germplasm diversity has been marker-genotyped or genome-sequenced. Accurate identification of genebank accessions is essential to improve the efficiency and effectiveness of global genebanking. It is crucial for preserving the legacy knowledge associated with the germplasm and for maintaining its value to current plant science and breeding efforts. Existing practices generally fall into two categories: either expensive and complex, or inefficient, labour-intensive, and inaccurate. The first relies on high-resolution genomic sequences or saturated markers, while the second relies on morphological comparisons of regenerated plants with historical records. We propose a genotyping method based on a minimal set of Single Nucleotide Polymorphism (SNP) markers and exemplify its use on a genebank scale. We identified a small, effective set of SNPs that can differentiate between the global diversity of genebank accessions of barley (Hordeum vulgare and Hordeum spontaneum) and tetraploid wheat collections (Triticum turgidum) maintained at the Germplasm Resources National Capability at the John Innes Centre, UK. This approach offers a straightforward, automatable, and inexpensive alternative to traditional genebank crop descriptors used during seed regeneration and distribution. By establishing the minimal genomic resolution needed to distinguish genetically distinct accessions, we show that as few as 24 and 25 carefully chosen SNP markers for barley and durum wheat, respectively, can effectively differentiate individual accessions. Unlike morphology-based identification, which can detect mislabelling or contamination but often cannot prevent or correct such errors, our SNP-based molecular labelling enables error correction and the retrieval of lost germplasm identity. This study highlights how accuracy and reliability in germplasm management can be improved without costly whole-genome sequencing or resource-intensive analysis. We discuss the impact of this method on enhancing quality assurance in genebanks and its broader usefulness for the user community. Full article

Backgrounds: Roegneria ciliaris is a perennial tetraploid wild relative of wheat that is widely distributed in China. It can be used both as a forage crop and ecological grass (the grasses specifically bred for ecological restoration) due to its strong stress tolerance, early green-up, vigorous seedling growth in spring, and great palatability. Methods: It is necessary to select and validate appropriate reference genes (RGs) for gene expression normalization by qRT-PCR in order to decipher the stress tolerance mechanism of this grass species. Therefore, eight candidate RGs were identified from transcriptome data of R. ciliaris ‘Liao sheng’ in response to drought stress. The expression stability of these RGs was evaluated by five algorithms (∆Ct, geNorm, NormFinder, Bestkeeper and ReFinder) using samples from different tissues and drought stress. Results: The results showed that MDH and RPL19 were the most stable RGs among all samples, while GAPDH and TUBA presented the lowest expression stability. These representative RGs were further used to normalize the expression level of the pyrroline-5-carboxylate synthase (P5CS) and protein phosphatase 2C (PP2C) genes in different tissues and under drought stress. The results of P5CS and PP2C expression were consistent with transcriptome data. Conclusion: Our study provided the first systematic evaluation of the most stable RG selection for qRT-PCR normalization in R. ciliaris, which will promote further research on its tissue-specific gene expression and mechanism of drought tolerance. Full article

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a highly destructive disease affecting wheat in most growing regions worldwide. The most effective strategy for combating this disease is through the exploitation of novel and durable resistance genes derived from the relatives of wheat. Rye (Secale cereale L.) has been extensively hybridized with both tetraploid and hexaploid wheats and represents a valuable genetic resource for enhancing resistance and tolerance to both biotic and abiotic stresses. In this study, two novel 1R (1D) substitution lines, R156 and R189, derived from hexaploid triticale lines Yukuri and T4915, respectively, were comprehensively characterized using non-denaturing fluorescence in situ hybridization (ND-FISH) and immunofluorescence. To physically map the 1R-derived powdery mildew resistance gene from Yukuri, 3485 M₁-M₃ plants from the cross between R156 and susceptible wheat cultivar MY11 were studied by ND-FISH using multiple probes. A cytological bin map for Yukuri chromosome 1R was constructed using 105 molecular markers. Resistance evaluation combined with molecular mapping revealed that the novel resistance locus resides in bin 1RS-4, corresponding to the 58.60–109.28 Mb genome region of Lo7 rye chromosome 1R. Thus, these newly developed wheat–rye 1R translocation and deletion lines are expected to serve as valuable genetic resources for breeding powdery mildew resistant wheat cultivars. Full article

The technological properties of durum wheat grain are determined by prolamins (gliadins and glutenins). Information on the allelic composition of key loci remains incomplete despite existing global studies examining prolamin variability. This highlighted the need to study these traits in durum wheat in Kazakhstan. The effects of specific gliadin components with high- and low-molecular-weight glutenin fractions on gluten quality are also not fully clarified. This study aimed to characterise allelic diversity at prolamin-coding loci and evaluate associated grain quality traits. Using native and denaturing SDS-electrophoresis, 181 tetraploid wheat accessions from Kazakhstan, an International germplasm collection, and 26 breeding lines were analysed for allelic variation and associations with protein content, gluten content, gluten index, and SDS-sedimentation. The γ45 gliadin component and Glu-A3a allele were positively associated with SDS-sedimentation and gluten index, while Glu-B3b had a negative effect. Distinct prolamin profiles were observed among accessions from different ecological and geographical locations. These results support the selection of superior durum wheat genotypes and enable the identification of favourable allele combinations at the Gli-1, Gli-2, Glu-1, and Glu-3 loci in cultivars from Kazakhstan. Comparison with global tetraploid wheat germplasm collections demonstrates unique genetic diversity in genotypes, providing a valuable basis for breeding programs aimed at improving grain and gluten quality in durum wheat in Kazakhstan and Central Asian countries. Full article

The genus Dasypyrum represents a valuable source of beneficial traits for wheat improvement, yet the cytogenetic organization of its genomes, particularly of the satellite repeats, remains poorly understood. This study aimed through comparative analysis of satellite DNA in diploid D. villosum (W6 21717, V genome) and tetraploid D. breviaristatum (PI 516547, VV^b genomes) to reveal the evolutionary dynamics of their subgenomes and to identify species-specific chromosomal markers. We performed whole-genome sequencing, bioinformatic analysis, and fluorescence in situ hybridization (FISH). Bioinformatic screening identified 14 satellite repeats in the D. breviaristatum genome (CL9, CL95, CL100, CL110, CL127, CL133, CL134, CL135, CL147, CL153, CL165, CL169, CL173, and CL197), which were classified by copy number: one as high-copy (CL9, ≥0.6%) and the rest as low-copy (<0.29%). Their monomer sizes ranged broadly from 118 to 1118 base pairs. Most repeats showed varying degrees of homology with known sequences from the Triticeae family, and one repeat, CL165, had no detectable homologs in existing databases. FISH analysis subdivided repeats into three groups: predominantly terminal (CL100, CL110, CL134, CL135, CL147, CL165, CL169, CL173, and CL197), pericentromeric (CL127 and CL133), and mixed localization (CL9). Significant species-specific differences were revealed, including emergence of tetraploid-specific repeats (CL110, CL134, CL135, CL147, CL165, and CL173) and the reorganization of conserved sequence distribution. Notably, the repeat CL135 was identified as a specific marker for the V subgenome within the allopolyploid D. breviaristatum. The obtained data support the allopolyploid origin of D. breviaristatum and demonstrate that these two species are genetically distinct but evolutionarily closely related. Chromosomal markers developed based on newly discovered satellite repeats open new avenues for investigating genomic architecture and evolutionary relationships within the genus Dasypyrum, as well as for identifying its chromatin in distant hybrids. Full article

Triticale, a man-made cereal, has been grown worldwide since the 1980s in order to replace established cereals in difficult areas, at least partially. The present cultivars are mostly hexaploid genotypes with 42 chromosomes, of genomic structure AA BB RR. Their agricultural performance does not meet all breeding requirements. In particular, some technological characteristics are inadequate compared to tetraploid (durum) and hexaploid (soft) wheats. Therefore, we aimed to find ways to improve modern triticale varieties by targeted introgression with genes and even chromosomes from wheat, in particular, from the D genome. Through appropriate bridge crossings and embryo culture technique and under cytogenetic control, a series of new stable hexaploid lines with reasonable agronomic stability were finally produced. All of them carried a complete D sub-genome, a complete R sub-genome, plus a mixed genome consisting of various combinations of chromosomes derived from the A and B genomes representing the seven homoeologous groups. It is clear that such mixed genomes can be of genetic and breeding significance. These large introgression lines demonstrate the flexibility of genome organization and offer the opportunity for further regulatory and genetic optimization. Full article

Wheat domestication and selection for aboveground traits may have influenced belowground traits, reducing genetic diversity critical for adaptation to stress such as drought. However, the impacts on root system architecture and root–endophytic fungal interactions remain unclear. This study evaluated variation in root traits and associations with arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) among nine diploid Aegilops tauschii accessions (wild progenitor), one tetraploid Triticum turgidum cv. ‘Langdon’ (LNG), and one hexaploid Triticum aestivum cv. ‘Norin 61’ (N61). Root traits and fungal colonization varied significantly among genotypes. All Ae. tauschii accessions showed superior root development and lower DSE colonization compared to LNG and N61. AMF colonization was highest in accessions AT76 and KU-2126 (54% and 53%, respectively), while N61 exhibited the highest specific root length (SRL) and DSE colonization. AMF positively correlated with most root traits (except SRL), while DSE showed the opposite trend. Although Ae. tauschii accessions shared broadly favorable root traits, variation in their fungal interactions were more pronounced. A clustering heatmap incorporating both root and biotic traits clustered the genotypes into four groups, clearly separating the Ae. tauschii accessions into two clusters based on their root characteristics and root-fungal associations. These results highlight the hidden interspecific and intraspecific variations in Ae. tauschii and its potential as a genetic resource for optimizing root–endophytic fungal interactions, and improving wheat resilience to biotic and abiotic stress in a changing climate. Full article

Phenolic compounds contribute significantly to the nutritional and functional properties of wheat, particularly due to their antioxidant activity. In this study, a genome-wide association study was conducted to elucidate the genetic basis of total phenolic content (TPC) and antioxidant activity (AA) in a panel of 144 tetraploid wheat accessions representing diverse subspecies. The panel was evaluated under two different environments, located in Chile and Italy, to assess the influence of genotype, environment, and their interaction. Significant variability was observed for both TPC and AA, with TPC ranging from 0.26 to 0.82 mg gallic acid equivalent (GAE)/g and AA from 0.04 to 0.99 µmol Trolox equivalent (TE)/g. Substantial phenotypic variation and high broad-sense heritability were observed for both traits, underscoring the predominant genetic control. The genome-wide association study, using a mixed linear model (MLM), and the Bayesian information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) approaches identified 17 significant marker–trait associations, including quantitative trait loci on chromosomes 2B, 3A, 4B, 5A, 5B, and 6B. Notably, QTLs on chromosome 5A were co-localized for both TPC and AA, suggesting potential pleiotropic loci. Candidate genes linked to these loci included flavonol 3-sulfotransferase and peptidylprolyl isomerase, which are involved in phenylpropanoid metabolism and oxidative stress response, respectively. These findings offer valuable insights into the genetic basis of wheat phenolic traits and provide molecular targets for the development of biofortified cultivars through marker-assisted selection. Full article

Modern wheat breeding has largely emphasized aboveground traits, often at the expense of belowground characteristics such as root biomass, architecture, and beneficial microbial associations. This has narrowed genetic diversity, impacting traits essential for stress resilience and efficient nutrient and water acquisition—factors expected to become increasingly critical under climate change. In this study, we evaluated 36 primary synthetic (PS) hexaploid wheat lines developed by crossing Aegilops tauschii with the durum wheat cultivar Langdon (LNG) and compared them with LNG and the hexaploid variety Norin 61 (N61). We observed significant variation in root length, biomass, and associations with fungal endophytes, including beneficial Arbuscular Mycorrhizal Fungi (AMF) and Serendipita indica, and pathogenic Alternaria sp. Clustering analysis based on these traits identified three distinct PS groups: (1) lines with greater root length and biomass, high AMF and S. indica colonization, and low Alternaria infection; (2) lines with intermediate traits; and (3) lines with reduced root traits and high Alternaria susceptibility. Notably, these phenotypic patterns corresponded closely with the soil classification of the Ae. tauschii progenitors’ origin, such as Cambisols (supportive of root growth), and Gleysols and Calcisols (restrictive of root growth). This highlights the soil microenvironment as a key determinant of belowground trait expression. By comparing PS lines with domesticated tetraploid and hexaploid wheat, we identified and selected PS lines derived from diverse Ae. tauschii with enhanced root traits. Our study emphasizes the potential of wild D-genome diversity to restore critical root traits for breeding resilient wheat. Full article

This study evaluated the potential of three ancient Sicilian tetraploid wheat genotypes—‘Margherito’, ‘Perciasacchi’, and ‘Russello’—for organic pasta production, compared to the national variety ‘Cappelli’. Significant variations in particle size distribution were found, with ‘Russello’ exhibiting the highest proportion of fine particles and the greatest protein content (14.30% d.m.). ‘Perciasacchi’ displayed the highest gluten index (81.26%). ‘Margherito’ and ‘Cappelli’ had the highest antioxidant activity, with ‘Margherito’ showing elevated levels of lutein and total carotenoids. Rheological analysis revealed differences in dough properties. ‘Perciasacchi’ exhibited the highest dough stability and P/L ratio (6.57), whereas ‘Russello’ showed the lowest values for both. Additionally, ‘Russello’ had lower consistency (12 B.U.), reduced gel stability, and limited water retention in the visco-amylographic analysis. Pasta quality was evaluated based on cooking time, water absorption, and texture. Cooking time ranged from 10 to 12 min, with ‘Russello’ and ‘Margherito’ showing lower water absorption. Texture analysis indicated that ‘Margherito’ pasta was the least firm, while ‘Russello’ showed the greatest loss of consistency when overcooked. From a sensory perspective, ‘Russello’ had lower firmness, but a stronger semolina flavor and surface roughness. ‘Cappelli’ had the most intense cooked pasta odor, while ‘Perciasacchi’ was the hardest and least sticky, though less flavorful. The results support the use of ancient tetraploid wheat genotypes as valuable resources for sustainable, high-quality pasta production. Full article