Bristling with potential: evaluating the effects of awns on yield under heat stress.

This article comments on: . 2023. Bearded or smooth? Awns improve yield when wheat experiences heat stress during grain fill in the southeastern United States.

The Triticum ispahanicum elongated glume locus P2 maps to chromosome 6A and is associated with the ectopic expression of SVP-A1.

We propose the MADS-box transcription factor SVP-A1 as a promising candidate gene for the elongated glume locus P2, which maps to chromosome 6A instead of the previously proposed chromosome 7B. In rice and wheat, glume and floral organ length are positively correlated with grain size, making them an important target to increase grain size and potentially yield. The wheat subspecies Triticum ispahanicum is known to develop elongated glumes and floral organs as well as long grains.

MicroRNA-resistant alleles of modify inflorescence branching and increase grain protein content of wheat.

Plant and inflorescence architecture determine the yield potential of crops. Breeders have harnessed natural diversity for inflorescence architecture to improve yields, and induced genetic variation could provide further gains. Wheat is a vital source of protein and calories; however, little is known about the genes that regulate the development of its inflorescence.

High expression of the MADS-box gene VRT2 increases the number of rudimentary basal spikelets in wheat.

Spikelets are the fundamental building blocks of Poaceae inflorescences, and their development and branching patterns determine the various inflorescence architectures and grain yield of grasses. In wheat (Triticum aestivum), the central spikelets produce the most and largest grains, while spikelet size gradually decreases acropetally and basipetally, giving rise to the characteristic lanceolate shape of wheat spikes. The acropetal gradient corresponds with the developmental age of spikelets; however, the basal spikelets are developed first, and the cause of their small size and rudimentary development is unclear.

A robust KASP marker for selection of four pairs of linked leaf rust and stripe rust resistance genes introgressed on chromosome arm 5DS from different wheat genomes.

Stripe rust and leaf rust are among the most devastating diseases of wheat, limiting its production globally. Wheat wild relatives harbour genetic diversity for new genes and alleles for all major wheat diseases. However, the use of this genetic variation from wild progenitor and non-progenitor species has been limited in the breeding programs.

Ectopic expression of Triticum polonicum VRT-A2 underlies elongated glumes and grains in hexaploid wheat in a dosage-dependent manner.

Flower development is an important determinant of grain yield in crops. In wheat (Triticum spp.), natural variation for the size of spikelet and floral organs is particularly evident in Triticum turgidum ssp.

A roadmap for gene functional characterisation in crops with large genomes: Lessons from polyploid wheat.

Understanding the function of genes within staple crops will accelerate crop improvement by allowing targeted breeding approaches. Despite their importance, a lack of genomic information and resources has hindered the functional characterisation of genes in major crops. The recent release of high-quality reference sequences for these crops underpins a suite of genetic and genomic resources that support basic research and breeding.

Aegilops umbellulata introgression carrying leaf rust and stripe rust resistance genes Lr76 and Yr70 located to 9.47-Mb region on 5DS telomeric end through a combination of chromosome sorting and sequencing.

Lr76 and Yr70 have been fine mapped using the sequence of flow-sorted recombinant 5D chromosome from wheat-Ae. umbellulata introgression line. The alien introgression has been delineated to 9.

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.

controls developmental responses of winter wheat under high ambient temperatures.

Low temperatures are required to regulate the transition from vegetative to reproductive growth via a pathway called vernalization. In wheat, vernalization predominantly involves the cold upregulation of the floral activator (). Here, we have used an extreme vernalization response, identified through studying ambient temperature responses, to reveal the complexity of temperature inputs into , with allelic inter-copy variation at a gene expansion of modulating these effects.

BED-domain-containing immune receptors confer diverse resistance spectra to yellow rust.

Crop diseases reduce wheat yields by ~25% globally and thus pose a major threat to global food security. Genetic resistance can reduce crop losses in the field and can be selected through the use of molecular markers. However, genetic resistance often breaks down following changes in pathogen virulence, as experienced with the wheat yellow (stripe) rust fungus Puccinia striiformis f.

Speed breeding is a powerful tool to accelerate crop research and breeding.

The growing human population and a changing environment have raised significant concern for global food security, with the current improvement rate of several important crops inadequate to meet future demand . This slow improvement rate is attributed partly to the long generation times of crop plants. Here, we present a method called 'speed breeding', which greatly shortens generation time and accelerates breeding and research programmes.

Transfer of a starch phenotype from wild wheat to bread wheat by deletion of a locus controlling B-type starch granule content.

Our previous genetic analysis of a tetraploid wild wheat species, Aegilops peregrina, predicted that a single gene per haploid genome, Bgc-1, controls B-type starch granule content in the grain. To test whether bread wheat (Triticum aestivum L.) has orthologous Bgc-1 loci, we screened a population of γ-irradiated bread wheat cv.

A Metabolic Gene Cluster in the Wheat W1 and the Barley Cer-cqu Loci Determines β-Diketone Biosynthesis and Glaucousness.

The glaucous appearance of wheat (Triticum aestivum) and barley (Hordeum vulgare) plants, that is the light bluish-gray look of flag leaf, stem, and spike surfaces, results from deposition of cuticular β-diketone wax on their surfaces; this phenotype is associated with high yield, especially under drought conditions. Despite extensive genetic and biochemical characterization, the molecular genetic basis underlying the biosynthesis of β-diketones remains unclear. Here, we discovered that the wheat W1 locus contains a metabolic gene cluster mediating β-diketone biosynthesis.

The Cer-cqu gene cluster determines three key players in a β-diketone synthase polyketide pathway synthesizing aliphatics in epicuticular waxes.

Aliphatic compounds on plant surfaces, called epicuticular waxes, are the first line of defense against pathogens and pests, contribute to reducing water loss and determine other important phenotypes. Aliphatics can form crystals affecting light refraction, resulting in a color change and allowing identification of mutants in their synthesis or transport. The present study discloses three such Eceriferum (cer) genes in barley - Cer-c, Cer-q and Cer-u - known to be tightly linked and functioning in a biochemical pathway forming dominating amounts of β-diketone and hydroxy-β-diketones plus some esterified alkan-2-ols.

Accession-specific modifiers act with ZWILLE/ARGONAUTE10 to maintain shoot meristem stem cells during embryogenesis in Arabidopsis.

Background: Stem cells located in the centre of the shoot apical meristem are required for the repetitive formation of new organs such as leaves, branches and flowers. In Arabidopsis thaliana, the ZWILLE/PINHEAD/AGO10 (ZLL) gene encodes a member of the ARGONAUTE (AGO) protein family and is required to maintain shoot meristem stem cells during embryogenesis. In the Landsberg erecta (Ler) acession, ZLL is essential for stem cell maintenance, whereas in the Columbia (Col) accession its requirement appears masked by genetic modifiers.

The inhibitor of wax 1 locus (Iw1) prevents formation of β- and OH-β-diketones in wheat cuticular waxes and maps to a sub-cM interval on chromosome arm 2BS.

Glaucousness is described as the scattering effect of visible light from wax deposited on the cuticle of plant aerial organs. In wheat, two dominant genes lead to non-glaucous phenotypes: Inhibitor of wax 1 (Iw1) and Iw2. The molecular mechanisms and the exact extent (beyond visual assessment) by which these genes affect the composition and quantity of cuticular wax is unclear.

Combining SNP discovery from next-generation sequencing data with bulked segregant analysis (BSA) to fine-map genes in polyploid wheat.

Background: Next generation sequencing (NGS) technologies are providing new ways to accelerate fine-mapping and gene isolation in many species. To date, the majority of these efforts have focused on diploid organisms with readily available whole genome sequence information. In this study, as a proof of concept, we tested the use of NGS for SNP discovery in tetraploid wheat lines differing for the previously cloned grain protein content (GPC) gene GPC-B1.

KLUH/CYP78A5 promotes organ growth without affecting the size of the early primordium.

Mobile signals play a key role in controlling the growth of organisms. In Arabidopsis, the cytochrome P450 CYP78A5/KLUH (KLU) non-cell autonomously stimulates cell proliferation in developing organs. In a recent study, we determined the range of KLU action, using a widely applicable system to generate predictable chimaeric plants.

KLUH/CYP78A5-dependent growth signaling coordinates floral organ growth in Arabidopsis.

Growth control in animals and plants involves mobile signals. Depending on their range of action, these signals coordinate the growth of cells within an organ or the growth of different organs in a larger, functionally integrated structure. In plants, flowers are such integrated structures, yet it remains poorly understood how growth of the constituent organs is coordinated to ensure their correct relative sizes.

Local maternal control of seed size by KLUH/CYP78A5-dependent growth signaling.

Seed development in plants involves the coordinated growth of the embryo, endosperm, and maternal tissue. Several genes have been identified that influence seed size by acting maternally, such as AUXIN RESPONSE FACTOR2, APETALA2, and DA1. However, given the lack of gain-of-function effects of these genes on seed size, it is unclear whether their activity levels are limiting in WT plants and whether they could thus be used to regulate seed size in development or evolution.