Barley Breeding Research Articles

Yield analysis of spring barley varieties under conditions of environmental variability

In conditions of increasing continentality of climate in recent decades, spring barley breeding should be aimed at creating drought-resistant, early-ripening, high-yielding varieties with sufficiently high technological qualities of grain. In addition to the economic and biological properties of the variety established by the breeders, external conditions in the region of cultivation also have a significant impact on the stabilization of the yields. The variability of productivity of spring barley varieties was assessed in terms of such traits as stability, ecological plasticity and adaptability in different ecological and geographical conditions. The research was conducted in 2020–2022 on 17 varieties of spring barley in ecological trial in Samara and Rostov regions. The experiment was laid in fourfold repetition with a plot area of 10 m². In the years of research, the "growing region" factor (98.7%) had the greatest influence. Evaluation of the index of environmental conditions (Ij) revealed that the best conditions for the vegetation of spring barley plants were formed in the experiment in the Rostov region (Zernogradsky district) (Ij = +0.99). The yield of the varieties depended not only on the location of the seed-trial ground but also on the year of cultivation. The linear regression coefficient ranged from 0.67 to 1.36, dividing the varieties into responsive, weakly responsive and adaptive to changes in the cultivation conditions. The varieties Zernogradsky 1717 and Zernogradsky 1724 formed the highest yield in the experimental plots and were classified as stable under cultivation under different soil and climatic conditions, with high breeding value, stress tolerance and level of variety stability.

Freezing tolerance and tolerance to de-acclimation of European accessions of winter and facultative barley

Due to global warming, winter hardiness may seem to become less important for plant survival and yield. However, this is a superficial assumption, as probably only the most important factors locally affecting plant overwintering will change. For example, the frequency, degree, and length of extreme winter warming events may increase, leading to de-acclimation of plants. This study aimed to investigate existing variability in de-acclimation tolerance in Polish winter barley breeding materials and European winter and facultative barley cultivars, and to identify accessions with the highest and the lowest tolerance to de-acclimation by means of visual estimation of regrowth after freezing, measurements of electrolyte leakage and chlorophyll fluorescence, and LT50 assessment. The results of this study showed that freezing tolerance and tolerance to de-acclimation are independent traits, and even highly freezing tolerant plants can be susceptible to de-acclimation. Our results highlight the role of photosynthetic apparatus in de-acclimation, proving that chlorophyll fluorescence parameters, especially ET0/CS, can be useful indicators of tolerance to de-acclimation. This study also confirmed that although the mechanisms of response to de-acclimation seem to be common for susceptible barley accessions, the mechanisms of tolerance are different, and may be related to the accession’s origin.

The improvement of the in vitro plant regeneration in barley with the epigenetic modifier of histone acetylation, trichostatin A

Genotype-limited plant regeneration is one of the main obstacles to the broader use of genetic transformation in barley breeding. Thus, developing new approaches that might improve responses of in vitro recalcitrant genotypes remains at the center of barley biotechnology. Here, we analyzed different barley genotypes, including “Golden Promise,” a genotype commonly used in the genetic transformation, and four malting barley cultivars of poor regenerative potential. The expression of hormone-related transcription factor (TF) genes with documented roles in plant regeneration was analyzed in genotypes with various plant-regenerating capacities. The results indicated differential expression of auxin-related TF genes between the barley genotypes in both the explants and the derived cultures. In support of the role of auxin in barley regeneration, distinct differences in the accumulation of free and oxidized auxin were observed in explants and explant-derived callus cultures of barley genotypes. Following the assumption that modifying gene expression might improve plant regeneration in barley, we treated the barley explants with trichostatin A (TSA), which affects histone acetylation. The effects of TSA were genotype-dependent as TSA treatment improved plant regeneration in two barley cultivars. TSA-induced changes in plant regeneration were associated with the increased expression of auxin biosynthesis-involved TFs. The study demonstrated that explant treatment with chromatin modifiers such as TSA might provide a new and effective epigenetic approach to improving plant regeneration in recalcitrant barley genotypes.

Breeding of the facultative barley varieties at the FSBSI ARC «Donskoy»

The current paper is devoted to the study of promising barley lines with an alternative type of development (facultative). Famous breeders P. F. Garkavy and V. M. Shevtsov believed that the future belonged to the facultative barley varieties, since they had high adaptive properties. Facultative varieties have several advantages, such as they can be used for early spring reseeding of sparse autumn crops of winter barley with seeds of the same variety and dead crops of winter cereals, as well as for obtaining high-quality seeds from spring sowing for autumn sowing. In connection with the above, the cultivation of facultative varieties for production is of great relevance and necessity. The purpose of the current study was to estimate new breeding material for facultative barley varieties in the conditions of the south of the Rostov region. The study was carried out in 2021–2023 in the fields of scientific crop rotation of the department of barley breeding and seed production of the ARC «Donskoy». In the first competitive variety testing there have been studied 12 promising facultative barley lines and the two currently best facultative barley varieties ‘Step’ and ‘Marusya’. There has been carried out comprehensive estimation of the studied samples based on such traits as the length of a vegetation period, resistance to lodging and damage by leaf diseases, 1000-grain weight, number of grains per an ear, number of productive stems per square meter, productivity. According to lodging resistance on average over three years, there were identified the varieties ‘Marusya’ and ‘Step’, as well as the lines Parallelum 2019, 2139, 2110, 2128, 2152, 2153 and Pallidum 2100; according to grain size the best varieties and lines were ‘Step’, ‘Marusya’, Parallelum 2141, 2110, 2128, 2149, 2152 and Pallidum 2100. The variety ‘Marusya’ and the lines Parallelum 2139, 2128, 2136, 2110, 2149, 2152, 2153 have shown the greatest productivity increase of 1 t/ha to the standard. Based on the data obtained, all studied varieties received a score based on a complex of economically valuable traits. The variety ‘Parallelum 2128’, which received the maximum number of points, was selected, and prepared for sending to the State Variety Commission of the Russian Federation for study.

Genome-Wide Association Mapping of Bacterial Leaf Streak Resistance in Two Elite Barley Breeding Panels.

Bacterial leaf streak (BLS), caused chiefly by the pathogen Xanthomonas translucens pv. translucens, is becoming an increasingly important foliar disease of barley in the Upper Midwest. The deployment of resistant cultivars is the most economical and practical method of control. To identify sources of BLS resistance, we evaluated two panels of breeding lines from the University of Minnesota (UMN) and Anheuser-Busch InBev (ABI) barley improvement programs for reaction to strain CIX95 in the field at St.Paul and Crookston, MN, in 2020 and 2021. The percentage of resistant lines in the UMN and ABI panels with mid-season maturity was 1.8% (6 of 333 lines) and 5.2% (13 of 251 lines), respectively. Both panels were genotyped with the barley 50K iSelect SNP array, and then a genome-wide association study was performed. A single, highly significant association was identified for BLS resistance on chromosome 6H in the UMN panel. This association was also identified in the ABI panel. Seven other significant associations were detected in the ABI panel: two each on chromosomes 1H, 2H, and 3H and one on chromosome 5H. Of the eight associations identified in the panels, five were novel. The discovery of resistance in elite breeding lines will hasten the time needed to develop and release a BLS-resistant cultivar.

Endogenic Phenolic Compounds of Barley as Potential Biomarkers Related to Grain Mycotoxin Production and Cultivar Selection.

Barley (Hordeum vulgare L.) is the fourth largest cereal crop in the world. One of the most devastating diseases in barley worldwide is Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe. Several mycotoxins are produced by FHB infection, and deoxynivalenol (DON) is one of them responsible for the deterioration of grain quality. The current limited number of reliable molecular markers makes the development of FHB-resistant cultivars rather difficult and laborious. Moreover, there is a limited number of designed specific biomarkers that could distinguish the FHB resistance and mycotoxin accumulation in barley cultivars. This study investigated the phenolic compounds of ten different Canadian barley cultivars, grown in artificially FHB-infected and non-infected field trials. The enzyme-linked immunosorbent assay (ELISA) was used to assess the presence of DON in the harvested infected grains of each tested variety. High-performance liquid chromatography (HPLC) analysis was performed using both infected and non-infected samples. We identified differences among cultivars tested in non-infected samples through quantitative analysis of free and bound phenolic compounds. The resistant cultivars showed higher amounts of major bound phenolic compounds compared to the susceptible check CDC Bold. Additionally, the FHB-infected cultivars produced significantly higher amounts of sinapic acid (SIN) () and catechin (CAT) in the soluble free form of phenolics in barley compared to the non-infected subjects. This study suggests that phenolic compounds in barley could allow barley breeders to precisely identify and develop FHB-resistant barley germplasm and cultivars.

Mapping QTL for Mineral Accumulation and Shoot Dry Biomass in Barley under Different Levels of Zinc Supply.

Zinc (Zn) deficiency is a common limiting factor in agricultural soils, which leads to significant reduction in both the yield and nutritional quality of agricultural produce. Exploring the quantitative trait loci (QTL) for shoot and grain Zn accumulation would help to develop new barley cultivars with greater Zn accumulation efficiency. In this study, two glasshouse experiments were conducted by growing plants under adequate and low Zn supply. From the preliminary screening of ten barley cultivars, Sahara (0.05 mg/pot) and Yerong (0.06 mg/pot) showed the lowest change in shoot Zn accumulation, while Franklin (0.16 mg/pot) had the highest change due to changes in Zn supply for plant growth. Therefore, the double haploid (DH) population derived from Yerong × Franklin was selected to identify QTL for shoot mineral accumulation and biomass production. A major QTL hotspot was detected on chromosome 2H between 31.91 and 73.12 cM encoding genes for regulating shoot mineral accumulations of Zn, Fe, Ca, K and P, and the biomass. Further investigation demonstrated 16 potential candidate genes for mineral accumulation, in addition to a single candidate gene for shoot biomass in the identified QTL region. This study provides a useful resource for enhancing nutritional quality and yield potential in future barley breeding programs.

Proteome Changes Resulting from Malting in Hordein-Reduced Barley Lines.

Hordeum vulgare L., commonly known as barley, is primarily used for animal feed and malting. The major storage proteins in barley are hordeins, known triggers of celiac disease (CD). Here, sequential window acquisition of all theoretical mass spectra (SWATH)-MS proteomics was employed to investigate the proteome profile of grain and malt samples from the malting barley cultivar Sloop and single-, double-, and triple hordein-reduced lines bred in a Sloop background. Using a discovery proteomics approach, 2688 and 3034 proteins were detected from the grain and malt samples, respectively. By utilizing label-free relative quantitation through SWATH-MS, a total of 2654 proteins have been quantified from grain and malt. The comparative analyses between the barley grain and malt samples revealed that the C-hordein-reduced lines have a more significant impact on proteome level changes due to malting than B- and D-hordein-reduced lines. Upregulated proteins in C-hordein-reduced lines were primarily involved in the tricarboxylic acid cycle and fatty acid peroxidation processes to provide more energy for seed germination during malting. By applying proteomics approaches after malting in hordein-reduced barley lines, we uncovered additional changes in the proteome driven by the genetic background that were not apparent in the sound grain. Our findings offer valuable insights for barley breeders and maltsters seeking to understand and optimize the performance of gluten-free grains in malt products.

Metabolomic-genomic prediction can improve prediction accuracy of breeding values for malting quality traits in barley

BackgroundMetabolomics measures an intermediate stage between genotype and phenotype, and may therefore be useful for breeding. Our objectives were to investigate genetic parameters and accuracies of predicted breeding values for malting quality (MQ) traits when integrating both genomic and metabolomic information. In total, 2430 plots of 562 malting spring barley lines from three years and two locations were included. Five MQ traits were measured in wort produced from each plot. Metabolomic features used were 24,018 nuclear magnetic resonance intensities measured on each wort sample. Methods for statistical analyses were genomic best linear unbiased prediction (GBLUP) and metabolomic-genomic best linear unbiased prediction (MGBLUP). Accuracies of predicted breeding values were compared using two cross-validation strategies: leave-one-year-out (LOYO) and leave-one-line-out (LOLO), and the increase in accuracy from the successive inclusion of first, metabolomic data on the lines in the validation population (VP), and second, both metabolomic data and phenotypes on the lines in the VP, was investigated using the linear regression (LR) method.ResultsFor all traits, we saw that the metabolome-mediated heritability was substantial. Cross-validation results showed that, in general, prediction accuracies from MGBLUP and GBLUP were similar when phenotypes and metabolomic data were recorded on the same plots. Results from the LR method showed that for all traits, except one, accuracy of MGBLUP increased when including metabolomic data on the lines of the VP, and further increased when including also phenotypes. However, in general the increase in accuracy of MGBLUP when including both metabolomic data and phenotypes on lines of the VP was similar to the increase in accuracy of GBLUP when including phenotypes on the lines of the VP. Therefore, we found that, when metabolomic data were included on the lines of the VP, accuracies substantially increased for lines without phenotypic records, but they did not increase much when phenotypes were already known.ConclusionsMGBLUP is a useful approach to combine phenotypic, genomic and metabolomic data for predicting breeding values for MQ traits. We believe that our results have significant implications for practical breeding of barley and potentially many other species.

Androgenic response of spring barley (Hordeum vulgare L.) varieties and lines – sources of high grain protein content

Aim. Protein content is known to be one of the most important characters of grain quality. Investigation was aimed to determine the capability to haploid production in anther culture in vitro of spring barley accessions which are the sources of high protein content in grain. Methods. Infrared spectroscopy was used for evaluation of variability of barley genotypes in protein content. Anthers isolated from cold-pretreated spikes were cultivated on agar solidified nutrient medium containing N6 macro-and MS micronutrients, physiologically active substances and maltose (9.0 %). Results. Three years testing showed that mean grain protein contents in six spring barley accessions varied from 12.6 to 19.1 %. Commercial variety Yavir, accessions IR06605 and DD-21 from germplasm collection of the National Plant Gene Pool of Ukraine were selected as genotypes with a stable expression of this char-acter. Response to androgenesis in vitro varied from 6.9 to 45.9 % of morphogenic anthers and from 0.64 до 14.7 green plants per 100 cultivated anthers in dependence of genotype and donor plant growth conditions. Conclusions. Because of association between high protein content in grains and a relatively high androgenic response, varieties Velikan and Yavir were considered to be the most valuable ones for use in spring barley breeding for improvement of protein content via anther culture in vitro.

Genomic signatures of barley breeding for environmental adaptation to the new continents.

Genomic signatures of barley breeding for environmental adaptation to the new continents.

Major chromosome 5H haplotype switch structures the European two-rowed spring barley germplasm of the past 190 years

Key messageSelection over 70 years has led to almost complete fixation of a haplotype spanning ~ 250 Mbp of chomosome 5H in European two-rowed spring barleys, possibly originating from North Africa.Plant breeding and selection have shaped the genetic composition of modern crops over the past decades and centuries and have led to great improvements in agronomic and quality traits. Knowledge of the genetic composition of breeding germplasm is essential to make informed decisions in breeding programs. In this study, we characterized the structure and composition of 209 barley cultivars representative of the European two-rowed spring barley germplasm of the past 190 years. Utilizing high-density SNP marker data, we identified a distinct centromeric haplotype spanning a ~ 250 Mbp large region on chromosome 5H which likely was first introduced into the European breeding germplasm in the early to mid-twentieth century and has been non-recombining and under strong positive selection over the past 70 years. Almost all cultivars in our panel that were released after 2000 carry this new haplotype, suggesting that this region carries one or several genes conferring highly beneficial traits. Using the global barley collection of the German Federal ex situ gene bank at IPK Gatersleben, we found the new haplotype at high frequencies in six-rowed spring-type landraces from Northern Africa, from which it may have been introduced into modern European barley germplasm via southern European landraces. The presence of a 250 Mbp genomic region characterized by lack of recombination and high levels of fixation in modern barley germplasm has substantial implications for the genetic diversity of the modern barley germplasm and for barley breeding.

Anthocyanins in Naked Pigmented Barley Grain as a Source of Antioxidant Activity

Anthocyanins and other phenolic compounds are powerful antioxidants, which reduce risks of many serious human diseases. Anthocyanin contents in naked pigmented barley grain have been determined in numerous studies. In Ukraine, the purpose of the breeding of barley with pigmented grain as a functional food product is biofortification of the grain nutritional value. Published data have demonstrated that it is possible to create high-yielding naked pigmented barley lines.

Determination of Optimum Gamma Ray Irradiation Doses for Hulless Barley (Hordeum vulgare var. nudum L. Hook. f.) Genotypes

The limited germplasm resources of hulless barley restrict the breeding of hulless barley with improved traits. Mutation techniques are an effective tool for generating variation for plant breeding studies. This study aimed to evaluate the impact of gamma-ray at different doses on certain seedling properties of M1 plants of two hulless barley genotypes, as well as determine the effective dose (ED50). The seeds of two hulless two-row barley genotypes, cv. Yalin and hulless barley line YAA7050-14, were irradiated with 100, 150, 200, 250, and 300 gray Gamma-rays delivered by a Cobalt 60 source along with non-irradiated control samples. Gamma-ray irradiation affects the seedling properties of M1 plants of both hulless barley genotypes significantly. The significant effect varied based on the doses, traits, and genotypes. While lower doses were found statistically identical to the control in the majority of qualities in the M1 generation, 250-300 gray gamma ray doses caused statistically significant decreases in the majority of characteristics studied in both genotypes. The effective doses (ED50) for hulless barley genotypes were determined by plotting growth reduction values of seedling lengths, then the polynomial regression equations were calculated for each genotype. It was determined that 50% growth reduction in shoot length was reached at 214.1 Gy and 253.4 Gy for cv. Yalin and line YAA7050-14, respectively.

Selection of High-Yielding and Stable Genotypes of Barley for the Cold Climate in Iran.

The interaction between genotypes and environments plays an important role in selecting superior genotypes for target locations. The main objectives of the present study were to analyze the effect of the genotype-by-environment interaction (GEI) and identify superior, newly developed, and promising barley genotypes for cold regions in Iran. For these purposes, a set of genotypes obtained from breeding programs for cold climates in Iran, along with two reference genotypes, were investigated at eight research stations (Tabriz, Ardabil, Arak, Miandoab, Mashhad, Jolge Rokh, Karaj, and Hamadan) during two consecutive growing seasons (2019-2020 and 2020-2021). The results of the freezing test (LT50) showed that most of the tested genotypes had significant cold tolerance at the seedling stage. Based on the additive main effect and multiplicative interaction (AMMI) analysis, environment (E) and GEI effects explained 49.44% and 16.55% of the total variation in grain yield, respectively. Using AMMI1 and AMMI2 models, G2 and G20 were found to be superior genotypes in terms of grain yield and stability. Moreover, AMMI-based stability parameters considered the G20 genotype to be the ideal genotype. A two-plot analysis of the genotype-by-environment interaction (GGE) biplot showed that the 16 experimental environments were grouped into 2 mega-environments. Of the test environments, ARK1 and KAJ2 had the highest discriminating power and representativeness ability, and these were identified as ideal environments for testing advanced genotypes for yield and stability performance during early barley breeding practices in cold areas in Iran. In conclusion, both AMMI and GGE biplot models identified several superior genotypes, among which G20, with a high average yield relative to the overall average yield and the lowest IPC1 score, was found to have high yield stability and is recommended for inclusion in breeding programs for cold climates in Iran.

Retrospective of barley breeding in the FSBSI “ARC “Donskoy”

The current paper has presented a historical excursion and an overview of scientific research on breeding and seed production of winter and spring barley in the Federal State Budgetary Scientific Institution Agricultural Research Center “Donskoy”. The Southern Federal District includes 8 subjects of the Russian Federation, namely Sevastopol; republics of Adygea, Kalmykia, Crimea; Krasnodar Territory, Astrakhan, Volgograd and Rostov regions. Barley is the main grain forage crop in terms of sown area. Don farmers have long shown interest in this valuable, diverse crop, very unpretentious to the cultivation conditions. Barley breeding work began in our institution in 1932 and is still ongoing, with short interruptions, to the present. Research was carried out in various areas: breeding of winter, spring and facultative barley, seed production and technology of their cultivation. In the XXI-st century, the researchers of the barley department developed new innovative directions in barley breeding, there were developed two-row brewing varieties with high malting rates (the variety ‘Randevu’) in winter barley breeding and in spring barley breeding there were developed fodder barley (green fodder) varieties (the variety ‘Novik’), which were previously absent in the State List of the Russian Federation. In 2014 there were opened new directions in the department, namely the development of hulles spring barley varieties and awnless winter barley varieties. Since 2016, there has been carried out an active work to identify winter barley lines that are genetically resistant to net blotch. Together with the All-Russian Research Institute of Radiology and Agroecology, there was carried out an estimation of the radiosensitivity of winter and spring barley varieties to identify varieties being resistant to the environmental stress factors. Based on research materials, there were successfully defended 11 candidate and two doctoral dissertations, there were published eight monographs and more than 400 scientific articles.

Fine mapping of a Fusarium crown rot resistant locus on chromosome arm 6HL in barley by exploiting near isogenic lines, transcriptome profiling, and a large near isogenic line-derived population

Key messageThis study reported validation and fine mapping of a Fusarium crown rot resistant locus on chromosome arm 6HL in barley using near isogenic lines, transcriptome sequences, and a large near isogenic line-derived population.Fusarium crown rot (FCR), caused by Fusarium pseudograminearum, is a chronic and serious disease affecting cereal production in semi-arid regions globally. The increasing prevalence of this disease in recent years is attributed to the widespread adoption of minimum tillage and stubble retention practices. In the study reported here, we generated eight pairs of near isogenic lines (NILs) targeting a putative QTL (Qcrs.caf-6H) conferring FCR resistance in barley. Assessing the NILs confirmed the large effect of this locus. Aimed to develop markers that can be reliably used in incorporating this resistant allele into breeding programs and identify candidate genes, transcriptomic analyses were conducted against three of the NIL pairs and a large NIL-derived population consisting of 1085 F7 recombinant inbred lines generated. By analyzing the transcriptomic data and the fine mapping population, Qcrs.caf-6H was delineated into an interval of 0.9 cM covering a physical distance of ~ 547 kb. Six markers co-segregating with this locus were developed. Based on differential gene expression and SNP variations between the two isolines among the three NIL pairs, candidate genes underlying the resistance at this locus were detected. These results would improve the efficiency of incorporating the targeted locus into barley breeding programs and facilitate the cloning of causal gene(s) responsible for the resistance.

Remotely Sensed Phenotypic Traits for Heritability Estimates and Grain Yield Prediction of Barley Using Multispectral Imaging from UAVs.

This study tested the potential of parametric and nonparametric regression modeling utilizing multispectral data from two different unoccupied aerial vehicles (UAVs) as a tool for the prediction of and indirect selection of grain yield (GY) in barley breeding experiments. The coefficient of determination (R2) of the nonparametric models for GY prediction ranged between 0.33 and 0.61 depending on the UAV and flight date, where the highest value was achieved with the DJI Phantom 4 Multispectral (P4M) image from 26 May (milk ripening). The parametric models performed worse than the nonparametric ones for GY prediction. Independent of the retrieval method and UAV, GY retrieval was more accurate in milk ripening than dough ripening. The leaf area index (LAI), fraction of absorbed photosynthetically active radiation (fAPAR), fraction vegetation cover (fCover), and leaf chlorophyll content (LCC) were modeled at milk ripening using nonparametric models with the P4M images. A significant effect of the genotype was found for the estimated biophysical variables, which was referred to as remotely sensed phenotypic traits (RSPTs). Measured GY heritability was lower, with a few exceptions, compared to the RSPTs, indicating that GY was more environmentally influenced than the RSPTs. The moderate to strong genetic correlation of the RSPTs to GY in the present study indicated their potential utility as an indirect selection approach to identify high-yield genotypes of winter barley.

Molecular insights into the responses of barley to yellow mosaic disease through transcriptome analysis

BackgroundBarley (Hordeum vulgare L.) represents the fourth most essential cereal crop in the world, vulnerable to barley yellow mosaic virus (BaYMV) and/or barley mild mosaic virus (BaMMV), leading to the significant yield reduction. To gain a better understanding of the mechanisms regarding barley crop tolerance to virus infection, we employed a transcriptome sequencing approach and investigated global gene expression among three barley varieties under both infected and control conditions. ResultsHigh-throughput sequencing outputs revealed massive genetic responses, reflected by the barley transcriptome after BaYMV and/or BaMMV infection. Significant enrichments in peptidase complex and protein processing in endoplasmic reticulum were clustered through Gene ontology and KEGG analysis. Many genes were identified as transcription factors, antioxidants, disease resistance genes and plant hormones and differentially expressed between infected and uninfected barley varieties. Importantly, general response genes, variety-specific and infection-specific genes were also discovered. Our results provide useful information for future barley breeding to resist BaYMV and BaMMV.ConclusionsOur study elucidates transcriptomic adaptations in barley response to BaYMV/BaMMV infection through high-throughput sequencing technique. The analysis outcome from GO and KEGG pathways suggests that BaYMV disease induced regulations in multiple molecular-biology processes and signalling pathways. Moreover, critical DEGs involved in defence and stress tolerance mechanisms were displayed. Further functional investigations focusing on these DEGs contributes to understanding the molecular mechanisms of plant response to BaYMV disease infection, thereby offering precious genetic resources for breeding barley varieties resistant to BaYMV disease.

Genomic prediction of agronomic and malting quality traits in six-rowed winter barley

While two-rowed barley is usually preferred for malting and beer-making, six-rowed malting barley varieties appeared in Europe around 30 years ago, and several breeders have dedicated improvement programs on this specific germplasm. In this study, we evaluated the feasibility of genomic prediction for yield and malting related traits using 679 breeding lines from two French barley breeders, as well as a set of recently registered varieties. These lines were evaluated in five locations and two harvest years in an unbalanced design. Although the germplasm from the two breeders does show some trend towards differentiation, globally the whole panel did not show a clear-cut genetic structure. Predictive ability of GBLUP was evaluated through random cross-validation within and across breeder sets, and using cross-prediction between breeder sets. Results show moderate to high predictive ability (PA), particularly for malt friability and β-glucan content, for which predictive ability of 0.8 was obtained with training populations as small as 105 registered varieties and across breeding sets. The long range of useful linkage disequilibrium in this particular germplasm allows using as few as 2000 to 5000 markers to obtain high PA. Other prediction methods such as Bayesian LASSO, Bayes Cpi or EGBLUP did not improve predictive ability. These results are very encouraging for implementing genomic prediction of malting quality traits in applied breeding programs.