New loci and candidate genes in spring two-rowed barley detected through meta-analysis of a field trial European network.

A dense genome-wide meta-analysis provides new QTLs, reveals breeding history trends and identifies new candidate genes for yield, plant height, grain weight, and heading time of spring barley. This study contributes new knowledge on quantitative trait loci (QTLs) and candidate genes for adaptive traits and yield in two-rowed spring barley. A meta-analysis of a network of field trials, varying in latitude and sowing date, with 151 cultivars across several European countries, increased QTL detection power compared to single-trial analyses.

Structural variation in the pangenome of wild and domesticated barley.

Pangenomes are collections of annotated genome sequences of multiple individuals of a species. The structural variants uncovered by these datasets are a major asset to genetic analysis in crop plants. Here we report a pangenome of barley comprising long-read sequence assemblies of 76 wild and domesticated genomes and short-read sequence data of 1,315 genotypes.

A GDSL-motif Esterase/Lipase Affects Wax and Cutin Deposition and Controls Hull-Caryopsis Attachment in Barley.

The cuticle covering aerial organs of land plants is well known to protect against desiccation. Cuticles also play diverse and specialized functions, including organ separation, depending on plant and tissue. Barley shows a distinctive cuticular wax bloom enriched in β-diketones on leaf sheaths, stem nodes and internodes and inflorescences.

Unlocking the genetic diversity and population structure of the newly introduced two-row spring European HerItage Barley collecTion (ExHIBiT).

In the last century, breeding programs have traditionally favoured yield-related traits, grown under high-input conditions, resulting in a loss of genetic diversity and an increased susceptibility to stresses in crops. Thus, exploiting understudied genetic resources, that potentially harbour tolerance genes, is vital for sustainable agriculture. Northern European barley germplasm has been relatively understudied despite its key role within the malting industry.

Measuring the frequency and distribution of meiotic crossovers in homozygous barley inbred lines.

We report a novel approach for establishing the number and position of CO events in individual homozygous inbred plants by combining low level EMS mutagenesis, speed breeding, whole genome shotgun sequencing and sliding window analysis of the induced molecular variant data. We demonstrate the approach by exploring CO frequency and distribution in self-fertilised progeny of the inbred barley cultivar Bowman and compare these observations to similar data obtained from a Bowman nearly isogenic line (BW230 containing a mutation in the DNA mismatch repair gene We have previously shown that decreases both plant fertility and recombination by ~50%. We compare our results to those from previously published traditional genetic analysis of F3 families derived from multiple F2 lines containing WT or mutant alleles of revealing a high level of correspondence between analyses.

Active and adaptive plasticity in a changing climate.

Better understanding of the mechanistic basis of plant plasticity will enhance efforts to breed crops resilient to predicted climate change. However, complexity in plasticity's conceptualisation and measurement may hinder fruitful crossover of concepts between disciplines that would enable such advances. We argue active adaptive plasticity is particularly important in shaping the fitness of wild plants, representing the first line of a plant's defence to environmental change.

An Induced Mutation in Increases the Overall Recombination and Restores Fertility in a Barley Mutant Background.

Plant breeding relies on the meiotic recombination or crossing over to generate the new combinations of the alleles along and among the chromosomes. However, crossing over is constrained in the crops such as barley by a combination of the low frequency and biased distribution. In this study, we attempted to identify the genes that limit the recombination by performing a suppressor screen for the restoration of fertility to the semi-fertile barley mutant (), carrying a mutation in the barley ortholog of (), a member of the MutL-homolog (MLH) family of DNA mismatch repair genes.

Trends of genetic changes uncovered by Env- and Eigen-GWAS in wheat and barley.

Variety age and population structure detect novel QTL for yield and adaptation in wheat and barley without the need to phenotype. The process of crop breeding over the last century has delivered new varieties with increased genetic gains, resulting in higher crop performance and yield. However, in many cases, the alleles and genomic regions underpinning this success remain unknown.

The proteome of developing barley anthers during meiotic prophase I.

Flowering plants reproduce sexually by combining a haploid male and female gametophyte during fertilization. Male gametophytes are localized in the anthers, each containing reproductive (meiocyte) and non-reproductive tissue necessary for anther development and maturation. Meiosis, where chromosomes pair and exchange their genetic material during a process called recombination, is one of the most important and sensitive stages in breeding, ensuring genetic diversity.

Downregulation of Barley Alters the Distribution of Meiotic Crossovers.

Programmed meiotic DNA double-strand breaks (DSBs), necessary for proper chromosomal segregation and viable gamete formation, are repaired by homologous recombination (HR) as crossovers (COs) or non-crossovers (NCOs). The mechanisms regulating the number and distribution of COs are still poorly understood. The regulator of telomere elongation helicase 1 (RTEL1) DNA helicase was previously shown to enforce the number of meiotic COs in but its function in plants has been studied only in the vegetative phase.

Overcoming barriers to the registration of new plant varieties under the DUS system.

Distinctness, Uniformity and Stability (DUS) is an intellectual property system introduced in 1961 by the International Union for the Protection of New Varieties of Plants (UPOV) for safeguarding the investment and rewarding innovation in developing new plant varieties. Despite the rapid advancement in our understanding of crop biology over the past 60 years, the DUS system has changed little and is still largely dependent upon a set of morphological traits for testing candidate varieties. As the demand for more plant varieties increases, the barriers to registration of new varieties become more acute and thus require urgent review to the system.

Barley Anther and Meiocyte Transcriptome Dynamics in Meiotic Prophase I.

In flowering plants, successful germinal cell development and meiotic recombination depend upon a combination of environmental and genetic factors. To gain insights into this specialized reproductive development program we used short- and long-read RNA-sequencing (RNA-seq) to study the temporal dynamics of transcript abundance in immuno-cytologically staged barley () anthers and meiocytes. We show that the most significant transcriptional changes in anthers occur at the transition from pre-meiosis to leptotene-zygotene, which is followed by increasingly stable transcript abundance throughout prophase I into metaphase I-tetrad.

The effect of heat stress on sugar beet recombination.

Meiotic recombination plays a crucial role in plant breeding through the creation of new allelic combinations. Therefore, lack of recombination in some genomic regions constitutes a constraint for breeding programmes. In sugar beet, one of the major crops in Europe, recombination occurs mainly in the distal portions of the chromosomes, and so the development of simple approaches to change this pattern is of considerable interest for future breeding and genetics.

Association mapping of malting quality traits in UK spring and winter barley cultivar collections.

Historical malting quality data was collated from UK national and recommended list trial data and used in a GWAS. 25 QTL were identified, with the majority from spring barley cultivar sets. In Europe, the most economically significant use of barley is the production of malt for use in the brewing and distilling industries.

A Modular Tray Growth System for Barley.

Determining when a barley plant starts and finishes meiosis is not trivial as when the spikelets undergo meiosis, the spike is not visible as it is still well within the leaf sheath on the developing tiller. This is a general constraint for any experiment involving meiosis, such as cytology, RNA extractions, or abiotic stress treatments aiming to target such a developmental stage. The lack of synchronicity between barley tillers within the same plant exacerbates the difficulty to determine the overall meiotic stage of a plant at a certain time.

Following the Formation of Synaptonemal Complex Formation in Wheat and Barley by High-Resolution Microscopy.

Wheat and barley have large genomes of 15 Gb and 5.1 Gb, respectively, which is much larger than the human genome (3.3 Gb).

A highly mutagenised barley ( Golden Promise) TILLING population coupled with strategies for screening-by-sequencing.

Background: We developed and characterised a highly mutagenised TILLING population of the barley () cultivar Golden Promise. Golden Promise is the 'reference' genotype for barley transformation and a primary objective of using this cultivar was to be able to genetically complement observed mutations directly in order to prove gene function. Importantly, a reference genome assembly of Golden Promise has also recently been developed.

Development and Quality of Barley Husk Adhesion Correlates With Changes in Caryopsis Cuticle Biosynthesis and Composition.

The caryopses of barley become firmly adhered to the husk during grain development through a cuticular cementing layer on the caryopsis surface. The degree of this attachment varies among cultivars, with poor quality adhesion causing "skinning", an economically significant grain quality defect for the malting industry. Malting cultivars encompassing a range of husk adhesion qualities were grown under a misting treatment known to induce skinning.

desynaptic5 carries a spontaneous semi-dominant mutation affecting Disrupted Meiotic cDNA 1 in barley.

Despite conservation of the process of meiosis, recombination landscapes vary between species, with large genome grasses such as barley (Hordeum vulgare L.) exhibiting a pattern of recombination that is very heavily skewed to the ends of chromosomes. We have been using a collection of semi-sterile desynaptic meiotic mutant lines to help elucidate how recombination is controlled in barley and the role of the corresponding wild-type (WT) meiotic genes within this process.

Characterisation of barley resistance to rhynchosporium on chromosome 6HS.

Major resistance gene to rhynchosporium, Rrs18, maps close to the telomere on the short arm of chromosome 6H in barley. Rhynchosporium or barley scald caused by a fungal pathogen Rhynchosporium commune is one of the most destructive and economically important diseases of barley in the world. Testing of Steptoe × Morex and CIho 3515 × Alexis doubled haploid populations has revealed a large effect QTL for resistance to R.

Preparation of Barley Pollen Mother Cells for Confocal and Super Resolution Microscopy.

Recombination (crossover) drives the release of genetic diversity in plant breeding programs. However, in barley, recombination is skewed toward the telomeric ends of its seven chromosomes, restricting the re-assortment of about 30% of the genes located in the centromeric regions of its large 5.1 Gb genome.

Development and Evaluation of a Barley 50k iSelect SNP Array.

High-throughput genotyping arrays continue to be an attractive, cost-effective alternative to sequencing based approaches. We have developed a new 50k Illumina Infinium iSelect genotyping array for barley, a cereal crop species of major international importance. The majority of SNPs on the array have been extracted from variants called in exome capture data of a wide range of European barley germplasm.

Association Mapping of Diastatic Power in UK Winter and Spring Barley by Exome Sequencing of Phenotypically Contrasting Variety Sets.

Diastatic Power (DP) is an important quality trait for malt used in adjunct brewing and distilling. Substantial genetic variation for DP exists within UK elite barley cultivars, but breeding progress has been slow due to the limited demand, compared to the overall barley market, and difficulties in assessing DP. Estimates of DP (taken from recommended and national list trials between 1994 and 2012) from a collection of UK elite winter and spring varieties were used to identify contrasting sets of high and low DP varieties.