Bread Wheat Breeding Research Articles

Identification of Climate-Smart Bread Wheat (Triticum aestivum L.) Germplasm for Optimum Moisture Areas of Ethiopia

Ethiopia's Bread Wheat Breeding Program conducts annual multi-environment yield trials to develop advanced wheat genotypes for Ethiopian wheat cultivation, ensuring a steady supply of new and improved varieties to meet production and marketing challenges. The objective of this research was to assess potential yield and the interactions between genotype and environment in wheat across multiple environments, as every cultivar has a distinct response to soil and climate. The BLUP analysis reveals that the 22AA and 22KU trials in 2022, along with 21KU trials in 2021 yielded high grain production, indicating optimal testing locations for distinguishing bread wheat genotypes and agroecologies. The study found that seven out of sixteen trials exhibited a higher genetic variance for yield, indicating high genotype discriminating power, with estimates ranging from 0.043 to 0.989 for genetic variance, 0.084 to 1.147 for error variance, and 72.7 to 96.4 for heritability. EBW202471 and EBW202473 are stable genotypes with good yield performance across correlated locations, with EBW202471 showing the highest yield (4.98 t/ha) and Deka showing a lower yield (4.07 t/ha). Three wheat genotypes, EBW202471, EBW202472, and EBW202473, were found to be moderately resistant to moderately susceptible to stem and yellow rust among 20 wheat genotypes. Finally, the two genotypes, EBW202471 and EBW202473, were advanced to National Performance Trials to evaluate their performance alongside top genotypes from regional federal research centers and to be released as new varieties.

Evaluation of Bread Wheat (Tritium aestivum L.) Genotype in Multi-environment Trials Using Enhanced Statistical Models

In varietal selection field trials, spatial variation and genotype by environment (GxE) interaction are frequent and present a major challenge to plant breeders comparing the genetic potential of several cultivars. To consistently select superior cultivars that increase agricultural production, bread wheat breeding studies must be evaluated using efficient statistical techniques. By modeling the interactions of geographical field trends and genotypes by environment interaction, this work aimed to forecast the genetic potential of bread wheat varieties across settings and improve selection tactics. The dataset utilized in this investigation consisted of sixteen multi-environment trials (MET) that were carried out using a randomized complete block design (RCBD), with two replications arranged in plot arrays of rows and columns. The findings showed that the factor analytical and spatial models were effective ways to analyze the data for this study under the linear mixed model. By ranking average Best Linear Unbiased Predictions (BLUPs) within clusters, the 16 bread wheat environments were grouped into three mega environments (C1, C2, and C3) based on yield. This served as a selection indicator. Ranking average BLUPs helped in the selection of superior and stable genotypes. The first cluster (C1)'s mean BLUP values were used to score the genotypes' performance; C2 and C3 were excluded because of their limited genetic variety and low genetic connection with the other trials. The genotypes with the highest potential based on this cluster were EBW192346 and EBW192347, chosen for a subsequent verification study to release a variety. The estimates for variance component parameters ranged from 0.013 to 3.024 for genetic variance and from 0.072 to 0.37 for error variance. Hence, scaling up the use of this efficient analysis method will improve the selection of superior bread wheat varieties.

Molecular cytogenetic characteristics of new spring bread wheat introgressive lines resistant to stem rust.

Anticipatory wheat breeding for pathogen resistance is key to preventing economically significant crop losses caused by diseases. Recently, the harmfulness of a dangerous wheat disease, stem rust, caused by Puccinia graminis f. sp. tritici, was increased in the main grain-producing regions of the Russian Federation. At the same time, importation of the Ug99 race (TTKSK) is still a possibility. In this regard, the transfer of effective resistance genes from related species to the bread wheat breeding material followed by the chromosomal localization of the introgressions and a marker analysis to identify known resistance genes is of great importance. In this work, a comprehensive analysis of ten spring bread wheat introgressive lines of the Federal Center of Agricultural Research of the South-East Region (L657, L664, L758, L935, L960, L968, L971, L995/1, L997 and L1110) was carried out. These lines were obtained with the participation of Triticum dicoccum, T. timopheevii, T. kiharae, Aegilops speltoides, Agropyron elongatum and Secale cereale. In this study, the lines were evaluated for resistance to the Ug99 race (TTKSK) in the Njoro, Kenya. Evaluation of introgression lines in the field for resistance to the Ug99 race (TTKSK) showed that four lines were immune, two were resistant, three were moderately resistant, and one had an intermediate type of response to infection. By cytogenetic analysis of these lines using fluorescent (FISH) and genomic (GISH) in situ hybridization, introgressions from Ae. speltoides (line L664), T. timopheevii (lines L758, L971, L995/1, L997 and L1110), Thinopyrum ponticum = Ag. elongatum (2n = 70) (L664, L758, L960, L971, L997 and L1110), as well as introgressions from T. dicoccum (L657 and L664), T. kiharae (L960) and S. cereale (L935 and L968) were detected. Molecular markers recommended for marker-oriented breeding were used to identify known resistance genes (Sr2, Sr25, Sr32, Sr1A.1R, Sr36, Sr38, Sr39 and Sr47). The Sr36 and Sr25 genes were observed in lines L997 and L1110, while line L664 had the Sr39+Sr47+Sr25 gene combination. In lines L935 and L968 with 3R(3D) substitution from S. cereale, gene resistance was presumably identified as SrSatu. Thus, highly resistant to both local populations of P. graminis and the Ug99 race, bread wheat lines are promising donors for the production of new varieties resistant to stem rust.

Wild grass-derived alleles represent a genetic architecture for the resilience of modern common wheat to stresses.

This review explores the integration of wild grass-derived alleles into modern bread wheat breeding to tackle the challenges of climate change and increasing food demand. With a focus on synthetic hexaploid wheat, this review highlights the potential of genetic variability in wheat wild relatives, particularly Aegilops tauschii, for improving resilience to multifactorial stresses like drought, heat, and salinity. The evolutionary journey of wheat (Triticum spp.) from diploid to hexaploid species is examined, revealing significant genetic contributions from wild grasses. We also emphasize the importance of understanding incomplete lineage sorting in the genomic evolution of wheat. Grasping this information is crucial as it can guide breeders in selecting the appropriate alleles from the gene pool of wild relatives to incorporate into modern wheat varieties. This approach improves the precision of phylogenetic relationships and increases the overall effectiveness of breeding strategies. This review also addresses the challenges in utilizing the wheat wild genetic resources, such as the linkage drag and cross-compatibility issues. Finally, we culminate the review with future perspectives, advocating for a combined approach of high-throughput phenotyping tools and advanced genomic techniques to comprehensively understand the genetic and regulatory architectures of wheat under stress conditions, paving the way for more precise and efficient breeding strategies.

Enhanced radiation use efficiency and grain filling rate as the main drivers of grain yield genetic gains in the CIMMYT elite spring wheat yield trial

Common wheat (Triticum aestivum L.) is a major staple food crop, providing a fifth of food calories and proteins to the world’s human population. Despite the impressive growth in global wheat production in recent decades, further increases in grain yield are required to meet future demands. Here we estimated genetic gain and genotype stability for grain yield (GY) and determined the trait associations that contributed uniquely or in combination to increased GY, through a retrospective analysis of top-performing genotypes selected from the elite spring wheat yield trial (ESWYT) evaluated internationally during a 14-year period (2003 to 2016). Fifty-six ESWYT genotypes and four checks were sown under optimally irrigated conditions in three phenotyping trials during three consecutive growing seasons (2018–2019 to 2020–2021) at Norman E. Borlaug Research Station, Ciudad Obregon, Mexico. The mean GY rose from 6.75 (24th ESWYT) to 7.87 t ha−1 (37th ESWYT), representing a cumulative increase of 1.12 t ha−1. The annual genetic gain for GY was estimated at 0.96% (65 kg ha−1 year−1) accompanied by a positive trend in genotype stability over time. The GY progress was mainly associated with increases in biomass (BM), grain filling rate (GFR), total radiation use efficiency (RUE_total), grain weight per spike (GWS), and reduction in days to heading (DTH), which together explained 95.5% of the GY variation. Regression lines over the years showed significant increases of 0.015 kg m−2 year−1 (p < 0.01), 0.074 g m−2 year−1 (p < 0.05), and 0.017 g MJ−1 year−1 (p < 0.001) for BM, GFR, and RUE_total, respectively. Grain weight per spike exhibited a positive but no significant trend (0.014 g year−1, p = 0.07), whereas a negative tendency for DTH was observed (− 0.43 days year−1, p < 0.001). Analysis of the top ten highest-yielding genotypes revealed differential GY-associated trait contributions, demonstrating that improved GY can be attained through different mechanisms and indicating that no single trait criterion is adopted by CIMMYT breeders for developing new superior lines. We conclude that CIMMYT’s Bread Wheat Breeding Program has continued to deliver adapted and more productive wheat genotypes to National partners worldwide, mainly driven by enhancing RUE_total and GFR and that future yield increases could be achieved by intercrossing genetically diverse top performer genotypes.

Correlation and Path Analysis for Yield and Yield Component Traits on Bread Wheat (Triticum aestivum L.) Genotypes

The research was conducted at Kulumsa Agricultural Research Center Main Station, during July–November, 2021 (Main cropping season) to study the association among traits and estimate the direct and indirect effects of various traits on grain yield of bread wheat genotypes. A total of 64 bread wheat genotypes were evaluated for 16 traits in 8×8 simple lattice design. Grain yields showed positive and highly significant at (p&lt;0.01) genotypic and phenotypic correlation with plant height, number of seeds spike-1, head weight, yield head-1, biomass yield, hectoliter weight, test weight and harvest index. Genotypic correlation coefficients were greater for all significantly correlated with grain yield studied traits than the corresponding phenotypic correlation coefficients, indicating inherent association of the characters, therefore, selection for these characters could improve grain yield. Genotypic path analysis of the direct effects revealed that days to maturity, number of spikelets spike-1, head weight, yield head-1, biomass yield, hectoliter weight, test weight and harvest index exerted direct positive effect on grain yield. Phenotypic path analysis of the direct effects showed that days to maturity, plant height, number of tillers plant-1, number of seeds spike-1, head height, yield head-1, biomass yield, test weight and harvest index had direct positive effect on grain yield. Therefore, these traits should be considered for bread wheat breeding program for yield improvement.

Identification of Sr67, a new gene for stem rust resistance in KU168-2 located close to the Sr13 locus in wheat

Key messageSr67 is a new stem rust resistance gene that represents a new resource for breeding stem rust resistant wheat cultivarsRe-appearance of stem rust disease, caused by the fungal pathogen Puccinia graminis f. sp. tritici (Pgt), in different parts of Europe emphasized the need to develop wheat varieties with effective resistance to local Pgt populations and exotic threats. A Kyoto University wheat (Triticum aestivum L.) accession KU168-2 was reported to carry good resistance to leaf and stem rust. To identify the genomic region associated with the KU168-2 stem rust resistance, a genetic study was conducted using a doubled haploid (DH) population from the cross RL6071 × KU168-2. The DH population was phenotyped with three Pgt races (TTKSK, TPMKC, and QTHSF) and genotyped using the Illumina 90 K wheat SNP array. Linkage mapping showed the resistance to all three Pgt races was conferred by a single stem rust resistance (Sr) gene on chromosome arm 6AL, associated with Sr13. Presently, four Sr13 resistance alleles have been reported. Sr13 allele-specific KASP and STARP markers, and sequencing markers all showed null alleles in KU168-2. KU168-2 showed a unique combination of seedling infection types for five Pgt races (TTKSK, QTHSF, RCRSF, TMRTF, and TPMKC) compared to Sr13 alleles. The phenotypic uniqueness of the stem rust resistance gene in KU168-2 and null alleles for Sr13 allele-specific markers showed the resistance was conferred by a new gene, designated Sr67. Since Sr13 is less effective in hexaploid background, Sr67 will be a good source of stem rust resistance in bread wheat breeding programs.

Differentiation of Triticum aestivum L. genotypes according to combination of yield and flour quality indicators

Purpose. Hence, the purpose of this study was to identify winter bread wheat (Triticum aestivum L.) cultivars and breeding lines giving high yields, with improved flour quality and with combination of these features.&#x0D; Materials and Methods. The study was conducted at the V.M. Remeslo Myronivka Institute of Wheat (MIW) of NAAS of Ukraine in 2019/20–2021/22. Ten new winter bread wheat cultivars and four promising breeding lines were evaluated. Winter wheat was grown in accordance with routine techniques in the Forest-Steppe of Ukraine. The yields were harvested and recorded in accordance with methods of qualification examination of plant varieties for suitability for dissemination in Ukraine. Winter bread wheat grain quality parameters were determined by conventional methods at the Grain Quality Laboratory MIW.&#x0D; Results and Discussion. There was a significant variability of yield and flour quality parameters depending on the conditions of the study years. On average across the winter bread wheat cultivars and breeding lines, the highest contents of protein (14.7%) and wet gluten content (31.9%) were recorded in 2019/20, but the lowest yield (3.40 t/ha) was harvested that year. In 2020/21, on the contrary, the yield was higher (6.46 t/ha), while the sedimentation value (59 mL), protein content (11.9%), and wet gluten content (27.4%) were lower. Cv. ‘MIP Aelita’, ‘MIP Vidznaka’ and breeding line ‘Lutescens 37548’ yielded significantly more than the check cultivar (‘Podolianka’; 5.05 t/ha; LSD05 = 0.33 t/ha). We singled out genotypes that on average in 2019/20–2021/22 were significantly superior to the check cultivar (‘Podolianka’) in term of protein content (‘MIP Nika’, ‘MIP Vidznaka’, ‘MIP Dovira’, ‘Lutescens 37548’, ‘Lutescens 60049’, and ‘Lutescens 60400’), sedimentation value (‘MIP Feieriia’, ‘Lutescens 37548’, ‘Lutescens 60049’, and ‘Lutescens 60302’) and wet gluten content (‘Lutescens 375480’). It should be noted that breeding line ‘Lutescens 37548’ significantly outperformed the check cultivar in all measured flour quality parameters. Based on combinations of high yield with several parameters of flour quality, cv. ‘MIP Aelita’ and ‘MIP Vidznaka’ and breeding lines ‘Lutescens 37548’, ‘Lutescens 60049’, and ‘Lutescens 60302’ were distinguished.&#x0D; Conclusions. The selected winter bread wheat cultivars and breeding lines can be used in breeding to create starting materials as sources of improved corresponding parameters of flour quality, a set of the investigated characteristics of flour quality and of combinations of high yield and good parameters of flour quality.

Wheat bZIPC1 interacts with FT2 and contributes to the regulation of spikelet number per spike

Key messageThe wheat transcription factor bZIPC1 interacts with FT2 and affects spikelet and grain number per spike. We identified a natural allele with positive effects on these two economically important traits.Loss-of-function mutations and natural variation in the gene FLOWERING LOCUS T2 (FT2) in wheat have previously been shown to affect spikelet number per spike (SNS). However, while other FT-like wheat proteins interact with bZIP-containing transcription factors from the A-group, FT2 does not interact with any of them. In this study, we used a yeast-two-hybrid screen with FT2 as bait and identified a grass-specific bZIP-containing transcription factor from the C-group, designated here as bZIPC1. Within the C-group, we identified four clades including wheat proteins that show Y2H interactions with different sets of FT-like and CEN-like encoded proteins. bZIPC1 and FT2 expression partially overlap in the developing spike, including the inflorescence meristem. Combined loss-of-function mutations in bZIPC-A1 and bZIPC-B1 (bzipc1) in tetraploid wheat resulted in a drastic reduction in SNS with a limited effect on heading date. Analysis of natural variation in the bZIPC-B1 (TraesCS5B02G444100) region revealed three major haplotypes (H1–H3), with the H1 haplotype showing significantly higher SNS, grain number per spike and grain weight per spike than both the H2 and H3 haplotypes. The favorable effect of the H1 haplotype was also supported by its increased frequency from the ancestral cultivated tetraploids to the modern tetraploid and hexaploid wheat varieties. We developed markers for the two non-synonymous SNPs that differentiate the bZIPC-B1b allele in the H1 haplotype from the ancestral bZIPC-B1a allele present in all other haplotypes. These diagnostic markers are useful tools to accelerate the deployment of the favorable bZIPC-B1b allele in pasta and bread wheat breeding programs.

Multivariate analyses, heritability and genotype environment interaction of bread wheat genotypes in Ethiopia

Considering the genetic variability of bread wheat is essential for the development of improved, high-yielding germplasm. The extent of genetic variability, heritability and genotype-environment interaction in 180 bread wheat (Triticum aestivumL.) genotypes was investigated using field-based phenotyping of 12 agro-morphological traits. The experiment was positioned at alpha lattice design in two replications in Ethiopia at Kulmsa agricultural research center, Meraro (substation of Kulmsa agricultural research center) and Holeta agricultural research center. Moderate heritability and genetic advance were observed in plant height (50 %, 5.5 %), spick length (38 %, 5.3 %), number of kernels per spick (50 %, 5.23 %), and thousand kernel weights (41 %, 4.38 %), respectively. The analysis discovered that the mean performance of grain yield per-plot was the highest at Kulmsa, implying that Kulmsa could be better for bread wheat to perform well. Phenotypic and genotypic associations of grain yield with number of kernels per speculate (0.42 and 0.99), spick weight (0.91 and 0.99), leaf area (0.14 and 0.55) were positive and significant correlated both at phenotypic and genotypic levels. Analysis of variance showed that highly significant differences for environment and genotype in which grain yields were significantly affected by environment, counted 55.22 % of the total variation, whereas genotype and genotype environment interaction accounted for 27.46 % and 17.44 %, respectively. Moreover, genotypes 53, 68 and 168 are high performing valuable genetic resources to be used in further bread wheat breeding program. Inclusively, the study provided valuable information for the bread wheat improvement.

Genetic gain of grain yield and quality in bread wheat cultivars representing 40 years of breeding in Morocco

Background. Knowledge about the genetic gain for fundamental traits over time is essential for a critical assessment and improvement of breeding programs, especially regarding staple crops like bread wheat.Materials and methods. To estimate the genetic gain in bread wheat breeding in Morocco, grain yield (GY) and grain protein content (GPC) data were collected from 12 multi-environment field trials for 20 bread wheat cultivars released between 1980 and 2022.Results and discussion. Analysis of variance highlighted a high significant variability between environments (E), cultivars (G), and a significant G × E interaction (P &lt; 0.001). Based on stability analysis, the modern cultivars released during the two last decades (2002–2012 and 2013–2022) showed the highest performances and wider stability than old ones, especially in low-yielding environments. Genetic gain (GG) for GY was 21.4 kg ha−1 yr−1 (0.75% yr–1) over 4 decades of breeding. This progress was declining when advancing in decades and ranged from 11% (from 1980–1990 to 1991–2001) to less than 7% (from 2002–2012 to 2013–2022). The GG in low and intermediate yielding environments were the most important (17.34% and 6.88% yr–1 respectively), while GG was nonsignificant in high-yielding environments (4.62% yr–1). Within the same period, GPC showed a nonsignificant negative trend of –0.007% (–0.002% yr–1), while derivative parameters from GY and GPC indicated high positive genetic progress. More efforts should be deployed to implement a good balance between yield performance and quality in the new released cultivars despite the negative correlation between these two traits (r = –0.36; P &lt; 0.001).Conclusion. Adopting advanced technologies, like genomic selection, adequate agronomic practices, and more efficient selection criteria are essential steps to further increase simultaneously grain yield and quality traits.

Towards carotenoid biofortification in wheat: identification of XAT-7A1, a multicopy tandem gene responsible for carotenoid esterification in durum wheat

Yellow pigment content, mainly due to the accumulation of carotenoids, is a quality trait in durum wheat grain as it confers the bright yellow color to pasta preferred by consumers. Also, carotenoids are essential nutrients exerting important biological functions in human health. Consequently, biofortification strategies have been developed in many crops to increase carotenoid content. In this context, carotenoid esterification is emerging as a new breeding target for wheat biofortification, as carotenoid esters have been found to promote both carotenoid accumulation and stability. Until recently, no carotenoid esters have been identified in significant proportions in durum wheat grains, and interspecific breeding programs have been started to transfer esterification ability from common wheat and Hordeum chilense.In this work, XAT-7A1 is identified as the gene responsible for carotenoid esterification in durum wheat. Sequencing, copy number variation and mapping results show that XAT-7A1 is organized as tandem or proximal GDSL esterase/lipase copies in chromosome 7A. Three XAT-7A1 haplotypes are described: Type 1 copies, associated with high levels of carotenoid esters (diesters and monoesters) production and high expression in grain development; Type 2 copies, present in landraces with low levels of carotenoid esters (monoesters) or no esters; and Type 3 copies, without the signal peptide, resulting in zero-ester phenotypes.The identification of XAT-7A1 is a necessary step to make the carotenoid esterification ability available for durum and bread wheat breeding, which should be focused on the Type 1 XAT-7A1 haplotype, which may be assessed as a single gene since XAT-7A1 copies are inherited together.

Genetic mapping of the wheat leaf rust resistance gene Lr19 and development of translocation lines to break its linkage with yellow pigment.

The leaf rust resistance gene Lr19, which is present on the long arm of chromosome 7E1 in Thinopyrum ponticum, was mapped within a 0.3-cM genetic interval, and translocation lines were developed to break its linkage with yellow pigmentation The leaf rust resistance locus Lr19, which was transferred to wheat (Triticum aestivum) from its relative Thinopyrum ponticum in 1966, still confers broad resistance to most known races of the leaf rust pathogen Puccinia triticina (Pt) worldwide. However, this gene has not previously been fine-mapped, and its tight linkage with a gene causing yellow pigmentation has limited its application in bread wheat breeding. In this study, we genetically mapped Lr19 using a bi-parental population from a cross of two wheat-Th. ponticum substitution lines, the Lr19-carrying line 7E1(7D) and the leaf rust-susceptible line 7E2(7D). Genetic analysis of the F2 population and the F2:3 families showed that Lr19 was a single dominant gene. Genetic markers allowed the gene to be mapped within a 0.3-cM interval on the long arm of Th. ponticum chromosome 7E1, flanked by markers XsdauK3734 and XsdauK2839. To reduce the size of the Th. ponticum chromosome segment carrying Lr19, the Chinese Spring Ph1b mutant was employed to promote recombination between the homoeologous chromosomes of the wheat chromosome 7D and the Th. ponticum chromosome 7E1. Two translocation lines with short Th. ponticum chromosome fragments carrying Lr19 were identified using the genetic markers closely linked to Lr19. Both translocation lines were resistant to 16 Pt races collected throughout China. Importantly, the linkage between Lr19 and yellow pigment content was broken in one of the lines. Thus, the Lr19 linked markers and translocation lines developed in this study are valuable resources in marker-assisted selection as part of common wheat breeding programs.

Bread wheat breeding for functional nutrition products

In a world of rapid economic growth, food security from the point of view of the nutrition profile has become of increasing interest. The development of biofortified colored wheat (black, purple and blue) adds nutritional and functional health benefits to energy-rich wheat. Cultivars and lines of colored bread wheat with a high content of anthocyanins, iron and zinc exhibit antioxidant and anti-inflammatory activity and have desirable properties for production and commercial use. Anthocyanins contained in colored wheat have a wide range of health effects, such as protection from metabolic syndromes, obesity, diabetes, hypertension and dyslipidemia. The idea of production anthocyanin-enriched wheat shapes people's way of life, as it is the main food crop in many countries. The achievements of breeding new high-quality productive varieties of cereals, with a large amount of antioxidants, allow them to be used to obtain a number of products for functional nutrition. The presented review is a compilation of currently available information about colored wheat in the most important aspects, including biochemistry, food industry, nutrition, genetics, selection and its influence on human health. Market formation and consumer awareness raising are vital tasks for its use as a functional food product on a large scale.

Characteristics of the Indian dwarf wheat variety ‘Sakara’

The current paper has described the method of developing a spring shot wheat variety (Triticum sphaerococcum Percival) Sakara and its characteristics. The purpose of the current study was to show the efficiency of the ongoing breeding work with Indian dwarf, using the variety ‘Sakara’ as an example, to increase grain productivity and resistance to leaf-stem fungal diseases, while maintaining the high grain quality characteristic of shot wheats. Research methods were adapted for shot wheat based on the methods adopted in spring bread wheat breeding. The developed variety has features characteristic for a species, namely a short strong non-lodging stem and, as a result, 9 points of lodging resistance; a shot kernel shape with 25.6 g of 1000-grain weight; a dense, non-drooping head; excellent quality indicators of grain and flour, according to most indicators corresponding to GOST 34702-2020 for strong wheat. The T. sphaerococcum species, due to its characteristic morphological features, has a lower grain productivity than T. aestivum, mean productivity of the variety ‘Sakara’ for three years of testing was 34 % less than that of the standard spring bread wheat variety ‘Yoldyz’. There has been shown that the developed variety in our soil-climatic zone is characterized by high field resistance to powdery mildew (2 points of resistance on average over the years), leaf rust (there were only single pustules during the years of a strong spread of the disease). With artificial infection of seeds with the inuclium of hard smut, the damage degree of the variety averaged 7 %. The first spring shot wheat variety ‘Sakara’ has been recommended in the State List of Breeding Achievements since 2023 for cultivation from 1 to 12 regions.

Effective sources of powdery mildew resistance among spring bread wheat for the northwest of the russian federation

Background. Bread wheat (Triticum aestivum L.) is one of the world’s main food crops. In Russia, its gross harvest in recent years has reached 21.079 million tons. Blumeria graminis is one of the most harmful diseases of bread wheat. Annual harvest losses can reach 10–30%. In Leningrad Province, powdery mildew appears almost every year on cereals. Development of cultivars resistant to powdery mildew is the most important trend in spring bread wheat breeding. Its progress is determined by new sources of effective resistance genes and their incorporation into promising spring bread wheat cultivars. The purpose of this work was to retest the seedling and adult resistance to powdery mildew in spring bread wheat accessions selected over a period of more than twenty years and redefine the effectiveness of disease resistance sources at the present time.Materials and methods. Since 2000, VIR has conducted a search for powdery mildew resistance among 1283 spring bread wheat accessions. The identified 36 sources of adult and seedling powdery mildew resistance were reevaluated in 2022. Field and laboratory studies into the resistance to the pathogen were performed according to VIR’s guidelines.Results and discussion. In 2022, field and laboratory studies of spring bread wheat cultivars revealed accessions with resistance to the pathogen in all phases of plant development. Six sources remained resistant to powdery mildew for 13–22 years, another six showed resistance for 7–12 years, and 8 cultivars were immune for 6 years. Resistance of 9 accessions identified for this trait in 2020 was confirmed.Conclusion. Field and laboratory research into the resistance of spring bread wheat accessions to the pathogen identified sources retaining seedling and adult resistance to the Leningrad population of powdery mildew for 7 years or more. These accessions are recommended for use in wheat breeding programs.

Breeding improvement of spring Indian dwarf wheat &lt;i&gt;Triticum sphaerococcum&lt;/i&gt; Percival under the conditions of the Middle Volga region

Background. Indian dwarf wheat (Triticum sphaerococcum Percival) has positive traits: round grain shape, excellent flour and grain quality, and a short stem, but it is difficult to develop cultivars of this species due to low productivity. The main problem in the improvement of T. sphaerococcum is the pleiotropic effect of grain roundness and ear compactness caused by the S-D1 and C2 genes. These genes are inherited together with negative features peculiar to this species: small grain, and low ear productivity. This paper presents the results of breeding improvement of Indian dwarf wheat from the VIR collection.Materials and methods. The research materials were five T. sphaerococcum accessions from the VIR collection, promising lines of Indian dwarf wheat released by the Tatar Research Institute of Agriculture, and regional reference cultivars. Conventional methods of spring bread wheat breeding were applied. Evaluation of main diseases was based on VIR’s methodological guidelines. Baking qualities were assessed using generally accepted methods and standards adopted in Russia.Results. The work resulted in producing competitive lines of T. sphaerococcum which surpassed the original accessions in yield and resistance to main fungal diseases, but their grain yield was lower than that of the reference bread wheat cultivar ‘Yoldyz’. High flour and grain quality levels of Indian dwarf wheat were confirmed. A patent was obtained for the Indian dwarf wheat cultivar ‘Sakara’.

Maintenance of UK bread baking quality: Trends in wheat quality traits over 50 years of breeding and potential for future application of genomic-assisted selection.

Improved selection of wheat varieties with high end-use quality contributes to sustainable food systems by ensuring productive crops are suitable for human consumption end-uses. Here, we investigated the genetic control and genomic prediction of milling and baking quality traits in a panel of 379 historic and elite, high-quality UK bread wheat (Triticum eastivum L.) varieties and breeding lines. Analysis of the panel showed that genetic diversity has not declined over recent decades of selective breeding while phenotypic analysis found a clear trend of increased loaf baking quality of modern milling wheats despite declining grain protein content. Genome-wide association analysis identified 24 quantitative trait loci (QTL) across all quality traits, many of which had pleiotropic effects. Changes in the frequency of positive alleles of QTL over recent decades reflected trends in trait variation and reveal where progress has historically been made for improved baking quality traits. It also demonstrates opportunities for marker-assisted selection for traits such as Hagberg falling number and specific weight that do not appear to have been improved by recent decades of phenotypic selection. We demonstrate that applying genomic prediction in a commercial wheat breeding program for expensive late-stage loaf baking quality traits outperforms phenotypic selection based on early-stage predictive quality traits. Finally, trait-assisted genomic prediction combining both phenotypic and genomic selection enabled slightly higher prediction accuracy, but genomic prediction alone was the most cost-effective selection strategy considering genotyping and phenotyping costs per sample.

Bread Wheat Biofortification for Grain Carotenoid Content by Inter-Specific Breeding

Bread wheat has traditionally been selected for whitish derived flours. As a consequence, the current varieties carry carotenogenic alleles associated with low grain carotenoid. In contrast, high grain yellow pigment content (YPC) has been a major target in durum wheat programs since yellow colour is an important aesthetic factor for pasta production. Phytoene synthase 1 (Psy1) genes have an important role in the determination of the carotenoid content in wheat. In this work, we have transferred the genes Psy1-A1 and Psy1-B1 from durum to bread wheat by inter-specific hybridization in order to evaluate the combined effect of these genes for the improvement of grain carotenoid content, as well as the development of carotenoid-enriched bread wheat lines. Inter-specific breeding coupled with a MAS approach based on Psy1-A1 and Psy1-B1 alleles has allowed the development of bread wheat pre-breeding lines with enhanced grain carotenoid content (16-23% mean). These biofortified lines have the potential to become new varieties or to be used as recurrent parents in bread wheat breeding programs.

Creation of initial material using embryoculture and remote hybridization in the breeding of winter bread wheat

Aim. The research was to improve the technology of creating genetic diversity of samples obtained by remote hybridization of soft winter wheat and speltum wheat with usuing the biotechnological link in the selection scheme. Methods. Remote hybridization of plants is an effective method of obtaining new starting material. The research was conducted in the biotechnology laboratory of the Uman National University of Horticulture during 2018–2022. The initial maternal form was the soft winter wheat varieties Artemisia, Smuglyanka, Zolotokolosa and the parental form was the winter spelt variety Zorya Ukrainy. After hybridization, immature twelve-day-old embryos were planted on modified versions of MS nutrient medium and cultivated at 25 °C in the dark until macrostructures were formed. Results. The technology of obtaining hybrid material by remote hybridization of Triticum aestivum L. / Triticum spelta L. and its use in the selection scheme of the biotechnological link has been improved. Conclusions. A nutrient medium for the development of immature hybrid wheat germs has been developed. The highest yield of seedlings (40.0% on average by genotype) on the modified Murashige-Skug medium, which included 1,5 mg/l 6-benzylaminopurine, 0,5 mg/l indolylacetic acid, 1,0 mg/l gibberellin, 2,0 mg/l glutamine, 2,0 mg/l glycine, 0,5 mg/l serine, 100,0 mg/l meso-inositol, 50,0 g/l sucrose was recorded. It was noted that the induction of the development of biomaterial from hybrid immature embryos is a genetically determined factor. The possibility of obtaining genetic diversity of forms that can be used by donors of genes of individual traits using embryo culture was shown.