Tracing post-domestication historical events and screening pre-breeding germplasm from large gene pools in wheat in the absence of phenotype data.

Wheat, particularly common wheat (Triticum aestivum L.), is a major crop accounting for 25% of the world cereal production and thriving in diverse ecogeographic regions. Its adaptation to diverse environments arises from its three distinct genomes adapted to different environments and post-domestication anthropogenic interventions.

Genome-wide association studies using multi-models and multi-SNP datasets provide new insights into pasmo resistance in flax.

Introduction: Flax ( L.) is an economically important crop due to its oil and fiber. However, it is prone to various diseases, including pasmo caused by the fungus .

Fully resolved assembly of Fusarium proliferatum DSM106835 genome.

In the United Arab Emirates, sudden decline syndrome (SDS) is a destructive disease of date palm caused by the soil-borne fungal pathogen Fusarium proliferatum (Fp) DSM106835. Here, a high-resolution genome assembly of Fp DSM106835 was generated using PacBio HiFi sequencing with Omni-C data to provide a high-quality chromatin-organised reference genome with 418 scaffolds, totalling 58,468,907 bp in length and an N50 value of 4,383,091 bp from which 15,580 genes and 16,321 transcripts were predicted. The assembly achieved a complete BUSCO score of 99.

Plant Genomics-Advancing Our Understanding of Plants.

Plant genomics has made significant progress in recent years, enabling researchers to identify genes and genomic regions responsible for plant growth, development, and stress response [...

Historical Selection, Adaptation Signatures, and Ambiguity of Introgressions in Wheat.

Wheat was one of the crops domesticated in the Fertile Crescent region approximately 10,000 years ago. Despite undergoing recent polyploidization, hull-to-free-thresh transition events, and domestication bottlenecks, wheat is now grown in over 130 countries and accounts for a quarter of the world's cereal production. The main reason for its widespread success is its broad genetic diversity that allows it to thrive in different environments.

Quantitative Trait Locus Mapping of Marsh Spot Disease Resistance in Cranberry Common Bean ( L.).

Common bean ( L.) is a food crop that is an important source of dietary proteins and carbohydrates. Marsh spot is a physiological disorder that diminishes seed quality in beans.

Insights into the Genetic Architecture and Genomic Prediction of Powdery Mildew Resistance in Flax ( L.).

Powdery mildew (PM), caused by the fungus in flax, can cause defoliation and reduce seed yield and quality. To date, one major dominant gene () and three quantitative trait loci (QTL) on chromosomes 1, 7 and 9 have been reported for PM resistance. To fully dissect the genetic architecture of PM resistance and identify QTL, a diverse flax core collection of 372 accessions augmented with an additional 75 breeding lines were sequenced, and PM resistance was evaluated in the field for eight years (2010-2017) in Morden, Manitoba, Canada.

Genome-wide signatures in flax pinpoint to adaptive evolution along its ecological gradient.

Background: Flax is one of the eight founder crops of agriculture. It is believed to have been domesticated as a long-day plant that has since spread to survive in a wide range of eco-geographic regions extending from the warm Indian subcontinent to the low latitude east African highlands and to the cool and high-latitude Eurasia. Understanding the genetic basis underlying its adaptation and selection events throughout its dispersion is essential to develop cultivars adapted to local environmental conditions.

Genome Assembly of the Canadian two-row Malting Barley cultivar AAC Synergy.

Barley (Hordeum vulgare L.) is one of the most important global crops. The six-row barley cultivar Morex reference genome has been used by the barley research community worldwide.

Identification of New Leaf Rust Resistance Loci in Wheat and Wild Relatives by Array-Based SNP Genotyping and Association Genetics.

Leaf rust caused by is the most widespread rust disease of wheat. As pathogen populations are constantly evolving, identification of novel sources of resistance is necessary to maintain disease resistance and stay ahead of this plant-pathogen evolutionary arms race. The wild genepool of wheat is a rich source of genetic diversity, accounting for 44% of the genes identified.

Genome-wide identification of ATP binding cassette (ABC) transporter and heavy metal associated (HMA) gene families in flax (Linum usitatissimum L.).

Background: The recent release of the reference genome sequence assembly of flax, a self-pollinated crop with 15 chromosome pairs, into chromosome-scale pseudomolecules enables the characterization of gene families. The ABC transporter and HMA gene families are important in the control of cadmium (Cd) accumulation in crops. To date, the genome-wide analysis of these two gene families has been successfully conducted in some plant species, but no systematic evolutionary analysis is available for the flax genome.

Loci harboring genes with important role in drought and related abiotic stress responses in flax revealed by multiple GWAS models.

QTNs associated with drought tolerance traits and indices were identified in a flax mini-core collection through multiple GWAS models and phenotyping at multiple locations under irrigated and non-irrigated field conditions. Drought is a critical phenomenon challenging today's agricultural sector. Crop varieties adapted to moisture deficit are becoming vital.

Evaluation of variant calling tools for large plant genome re-sequencing.

Background: Discovering single nucleotide polymorphisms (SNPs) from agriculture crop genome sequences has been a widely used strategy for developing genetic markers for several applications including marker-assisted breeding, population diversity studies for eco-geographical adaption, genotyping crop germplasm collections, and others. Accurately detecting SNPs from large polyploid crop genomes such as wheat is crucial and challenging. A few variant calling methods have been previously developed but they show a low concordance between their variant calls.

A phenylpropanoid diglyceride associates with the leaf rust resistance Lr34res gene in wheat.

The gene Lr34res is one of the most long-lasting sources of quantitative fungal resistance in wheat. It is shown to be effective against leaf, stem, and stripe rusts, as well as powdery mildew and spot blotch. Recent biochemical characterizations of the encoded ABC transporter have outlined a number of allocrites, including phospholipids and abscisic acid, consistent with the established general promiscuity of ABC transporters, but ultimately leaving its mechanism of rust resistance unclear.

Mapping Quantitative Trait Loci onto Chromosome-Scale Pseudomolecules in Flax.

Quantitative trait loci (QTL) are genomic regions associated with phenotype variation of quantitative traits. To date, a total of 313 QTL for 31 quantitative traits have been reported in 14 studies on flax. Of these, 200 QTL from 12 studies were identified based on genetic maps, the scaffold sequences, or the pre-released chromosome-scale pseudomolecules.

Genomic Prediction Accuracy of Seven Breeding Selection Traits Improved by QTL Identification in Flax.

Molecular markers are one of the major factors affecting genomic prediction accuracy and the cost of genomic selection (GS). Previous studies have indicated that the use of quantitative trait loci (QTL) as markers in GS significantly increases prediction accuracy compared with genome-wide random single nucleotide polymorphism (SNP) markers. To optimize the selection of QTL markers in GS, a set of 260 lines from bi-parental populations with 17,277 genome-wide SNPs were used to evaluate the prediction accuracy for seed yield (YLD), days to maturity (DTM), iodine value (IOD), protein (PRO), oil (OIL), linoleic acid (LIO), and linolenic acid (LIN) contents.

Genome-wide introgression from a bread wheat × Lophopyrum elongatum amphiploid into wheat.

We introgressed wheatgrass germplasm from the octoploid amphiploid Triticum aestivum× Lophopyrum elongatum into wheat by manipulating the wheat Ph1 gene and discovered and characterized 130 introgression lines harboring single or, in various combinations, complete and recombined L. elongatum chromosomes. Diploid wheatgrass Lophopyrum elongatum (genomes EE) possesses valuable traits for wheat genetics and breeding.

The Complex Genetic Architecture of Early Root and Shoot Traits in Flax Revealed by Genome-Wide Association Analyses.

Roots are fundamental organs for water and nutrient uptake as well as for signal transduction in response to biotic and abiotic stresses. Flax has a shallow tap root system that relies mostly on top soil nutrient and moisture resources. The crop can easily be outcompeted by weeds or other crops in intercropping systems, especially in moisture deficit conditions.

Dominant inhibition of awn development by a putative zinc-finger transcriptional repressor expressed at the B1 locus in wheat.

Awns, bristle-like structures extending from grass lemmas, provide protection against predators, contribute to photosynthesis and aid in grain dispersal. In wheat, selection of awns with minimal extension, termed awnletted, has occurred during domestication by way of loci that dominantly inhibit awn development, such as Tipped1 (B1), Tipped2 (B2), and Hooded (Hd). Here we identify and characterize the B1 gene.

The genetic structure of flax illustrates environmental and anthropogenic selections that gave rise to its eco-geographical adaptation.

Flax, one of the eight founder crops of agriculture, has been cultivated for its oil and/or fiber for millennia. Understanding genetic divergence and geographic origins of germplasm in line with their cultivation history and ecological adaptation are essential for conservation and breeding. Here we performed a genome-wide assessment based on more than 51,000 single nucleotide polymorphic sites defining 383 flax accessions from a core collection representing 37 flax growing countries.

Sequencing a × hybrid yields high-quality genome assemblies of parental species.

Members of the genus are monecious wind-pollinated trees in the family Juglandaceae with highly heterozygous genomes, which greatly complicates genome sequence assembly. The genomes of interspecific hybrids are usually comprised of haploid genomes of parental species. We exploited this attribute of interspecific hybrids to avoid heterozygosity and sequenced an interspecific hybrid  ×  using a novel combination of single-molecule sequencing and optical genome mapping technologies.

Genome-Wide Association Studies for Pasmo Resistance in Flax (.).

Pasmo is one of the most widespread diseases threatening flax production. To identify genetic regions associated with pasmo resistance (PR), a genome-wide association study was performed on 370 accessions from the flax core collection. Evaluation of pasmo severity was performed in the field from 2012 to 2016 in Morden, MB, Canada.

Evaluation of Genomic Prediction for Pasmo Resistance in Flax.

Pasmo () is a fungal disease causing major losses in seed yield and quality and stem fibre quality in flax. Pasmo resistance (PR) is quantitative and has low heritability. To improve PR breeding efficiency, the accuracy of genomic prediction (GP) was evaluated using a diverse worldwide core collection of 370 accessions.

Genome-wide regulatory gene-derived SSRs reveal genetic differentiation and population structure in fiber flax genotypes.

We designed a set of 580 simple sequence repeat markers; 506 from transcription factor-coding genes, and 74 from long non-coding RNAs and designated them as regulatory gene-derived simple sequence repeat (ReG-SSR) markers. From this set, we could anchor 559 ReG-SSR markers on 15 flax chromosomes with an average marker distance of 0.56 Mb.