Barley heads east: Genetic analyses reveal routes of spread through diverse Eurasian landscapes

One of the world’s most important crops, barley, was domesticated in the Near East around 11,000 years ago. Barley is a highly resilient crop, able to grown in varied and marginal environments, such as in regions of high altitude and latitude. Archaeobotanical evidence shows that barley had spread throughout Eurasia by 2,000 BC. To further elucidate the routes by which barley cultivation was spread through Eurasia, simple sequence repeat (SSR) analysis was used to determine genetic diversity and population structure in three extant barley taxa: domesticated barley (Hordeum vulgare L. subsp. vulgare), wild barley (H. vulgare subsp. spontaneum) and a six-rowed brittle rachis form (H. vulgare subsp. vulgare f. agriocrithon (Åberg) Bowd.). Analysis of data using the Bayesian clustering algorithm InStruct suggests a model with three ancestral genepools, which captures a major split in the data, with substantial additional resolution provided under a model with eight genepools. Our results indicate that H. vulgare subsp. vulgare f. agriocrithon accessions and Tibetan Plateau H. vulgare subsp. spontaneum are closely related to the H. vulgare subsp. vulgare in their vicinity, and are therefore likely to be feral derivatives of H. vulgare subsp. vulgare. Under the eight genepool model, cultivated barley is split into six ancestral genepools, each of which has a distinct distribution through Eurasia, along with distinct morphological features and flowering time phenotypes. The distribution of these genepools and their phenotypic characteristics is discussed together with archaeological evidence for the spread of barley eastwards across Eurasia

Genetic dissection of photoperiod response based on GWAS of pre-anthesis phase duration in spring barley

Heading time is a complex trait, and natural variation in photoperiod responses is a major factor controlling time to heading, adaptation and grain yield. In barley, previous heading time studies have been mainly conducted under field conditions to measure total days to heading. We followed a novel approach and studied the natural variation of time to heading in a world-wide spring barley collection (218 accessions), comprising of 95 photoperiod-sensitive (Ppd-H1) and 123 accessions with reduced photoperiod sensitivity (ppd-H1) to long-day (LD) through dissecting pre-anthesis development into four major stages and sub-phases. The study was conducted under greenhouse (GH) conditions (LD; 16/8 h; ∼20/∼16°C day/night). Genotyping was performed using a genome-wide high density 9K single nucleotide polymorphisms (SNPs) chip which assayed 7842 SNPs. We used the barley physical map to identify candidate genes underlying genome-wide association scans (GWAS). GWAS for pre-anthesis stages/sub-phases in each photoperiod group provided great power for partitioning genetic effects on floral initiation and heading time. In addition to major genes known to regulate heading time under field conditions, several novel QTL with medium to high effects, including new QTL having major effects on developmental stages/sub-phases were found to be associated in this study. For example, highly associated SNPs tagged the physical regions around HvCO1 (barley CONSTANS1) and BFL (BARLEY FLORICAULA/LEAFY) genes. Based upon our GWAS analysis, we propose a new genetic network model for each photoperiod group, which includes several newly identified genes, such as several HvCO-like genes, belonging to different heading time pathways in barley

In Situ Small-Angle X-ray Scattering Studies During Reversible Addition–Fragmentation Chain Transfer Aqueous Emulsion Polymerization

Polymerization-induced self-assembly (PISA) is a powerful platform technology for the rational and efficient synthesis of a wide range of block copolymer nano-objects (e.g., spheres, worms or vesicles) in various media. In situ small-angle X-ray scattering (SAXS) studies of reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization have previously provided detailed structural information during self-assembly (see M. J. Derry et al., Chem. Sci. 2016, 7, 5078–5090). However, conducting the analogous in situ SAXS studies during RAFT aqueous emulsion polymerizations poses a formidable technical challenge because the inherently heterogeneous nature of such PISA formulations requires efficient stirring to generate sufficiently small monomer droplets. In the present study, the RAFT aqueous emulsion polymerization of 2-methoxyethyl methacrylate (MOEMA) has been explored for the first time. Chain extension of a relatively short non-ionic poly(glycerol monomethacrylate) (PGMA) precursor block leads to the formation of sterically-stabilized PGMA-PMOEMA spheres, worms or vesicles, depending on the precise reaction conditions. Construction of a suitable phase diagram enables each of these three morphologies to be reproducibly targeted at copolymer concentrations ranging from 10 to 30% w/w solids. High MOEMA conversions are achieved within 2 h at 70 °C, which makes this new PISA formulation well-suited for in situ SAXS studies using a new reaction cell. This bespoke cell enables efficient stirring and hence allows in situ monitoring during RAFT emulsion polymerization for the first time. For example, the onset of micellization and subsequent evolution in particle size can be studied when preparing PGMA29-PMOEMA30 spheres at 10% w/w solids. When targeting PGMA29-PMOEMA70 vesicles under the same conditions, both the micellar nucleation event and the subsequent evolution in the diblock copolymer morphology from spheres to worms to vesicles are observed. These new insights significantly enhance our understanding of the PISA mechanism during RAFT aqueous emulsion polymerization

Dissecting the genetic basis of wheat blast resistance in the Brazilian wheat cultivar BR 18-Terena.

Background: Wheat blast, caused by Magnaporthe oryzae Triticum (MoT) pathotype, is a global threat to wheat (Triticum aestivum L.) production. Few blast resistance (R) genes have been identified to date, therefore assessing potential sources of resistance in wheat is important. The Brazilian wheat cultivar BR 18-Terena is considered one of the best sources of resistance to blast and has been widely used in Brazilian breeding programmes, however the underlying genetics of this resistance are unknown. Results: BR 18-Terena was used as the common parent in the development of two recombinant inbred line (RIL) F6 populations with the Brazilian cultivars Anahuac 75 and BRS 179. Populations were phenotyped for resistance at the seedling and heading stage using the sequenced MoT isolate BR32, with transgressive segregation being observed. Genetic maps containing 1779 and 1318 markers, were produced for the Anahuac 75 × BR 18-Terena and BR 18- Terena × BRS 179 populations, respectively. Five quantitative trait loci (QTL) associated with seedling resistance, on chromosomes 2B, 4B (2 QTL), 5A and 6A, were identified, as were four QTL associated with heading stage resistance (1A, 2B, 4A and 5A). Seedling and heading stage QTL did not co-locate, despite a significant positive correlation between these traits, indicating that resistance at these developmental stages is likely to be controlled by different genes. BR 18-Terena provided the resistant allele for six QTL, at both developmental stages, with the largest phenotypic effect conferred by a QTL being 24.8% suggesting that BR 18-Terena possesses quantitative resistance. Haplotype analysis of 100 Brazilian wheat cultivars indicates that 11.0% of cultivars already possess a BR 18-Terenalike haplotype for more than one of the identified heading stage QTL. Conclusions: This study suggests that BR 18-Terena possesses quantitative resistance to wheat blast, with nine QTL associated with resistance at either the seedling or heading stage being detected. Wheat blast resistance is also largely tissue-specific. Identification of durable quantitative resistances which can be combined with race-specific R gene-mediated resistance is critical to effectively control wheat blast. Collectively, this work facilitates markerassisted selection to develop new varieties for cultivation in regions at risk from this emerging disease

Relationship between psychological and biological factors and physical activity and exercise behaviour in Filipino students

The aim of the present study was threefold. Firstly, it investigated whether a general measure or specific measure of motivational orientation was better in describing the relationship between motivation and exercise behaviour. Secondly, it examined the relationship between the four most popular indirect methods of body composition assessment and physical activity and exercise patterns. Thirdly, the interaction between motivation and body composition on physical activity and exercise behaviour was explored in a sample of 275 Filipino male and female students. Males were found to have higher levels of exercise whereas females had higher levels of physical activity. Furthermore, general self-motivation together with body weight and percentage body fat were found to be the best predictor of exercise behaviour whereas the tension/pressure subscale of the ‘Intrinsic Motivation Inventory’ (IMI) was the best predictor of levels of physical activity. However, significant gender differences were observed. That is, for the males only self-motivation and for the females only body weight and BMI predicted exercise behaviour. Also, tension/pressure predicted physical activity levels for the females but not the males. No inverse relationship was found between the four body composition measures and exercise and physical activity behaviour. The results support the notion that the psychobiological approach might be particularly relevant for high intensity exercise situations but also highlights some important gender differences. Finally, the results of this study emphasise the need for more cross-cultural research

The trans-Eurasian crop exchange in prehistory: Discerning pathways from barley phylogeography

A number of crops that are of global importance today, including wheat (Triticum spp) and barley (Hordeum vulgare), were domesticated in Southwest Asia between 10,000 and 11,000 years ago and subsequently spread through the Old World, into Europe, North Africa and eastwards across Eurasia. Their routes of expansion have been a focus of debate and are increasingly being revealed by widespread dating of archaeobotanical remains from across Eurasia. Of particular interest is work by Zhao (2009) who proposed three routes for the spread of wheat into China: firstly, across the Eurasian Steppe, second by sea from India to the east coast of Eurasia and third, along the Hexi Corridor, which forms part of the Silk Road in western China. Molecular genetic analysis of cereal landraces have also elucidated routes of expansion of cereal cultivation and, in addition, have revealed how crops adapted to changing environments as they moved away from their centres of domestication. Genes involved in flowering time genes have been a particular focus of these studies, including the photoperiod response gene Ppd-H1 in barley, which controls flowering in response to increasing day-lengths in the spring. In this paper we present a phylogeographic analysis of Old World landrace and wild barley, through the analysis of a portion of the Ppd-H1 DNA sequence. We discuss the geographic distribution of different haplotypes of this gene across Eurasia in the light of Zhao (2009)'s three routes and what it potentially reveals about trans-Eurasian pathways of contact between early farming communities.This research was conducted under the auspices of the ‘Food Globalization in Prehistory’ (FOGLIP, ERC grant number 249642) and ‘Origins and Spread of Agriculture in the South West Mediterranean Region’ (AgriWestMed, ERC Grant Number 230561) research projects, both funded by the European Research Council

Hidden Voices: Disabled Women's Experiences of Violence and Support Over the Life Course

Violence against women is a worldwide social and human rights problem that cuts across cultural, geographic, religious, social, and economic boundaries. It affects women in countries around the world, regardless of class, religion, disability, age, or sexual identity. International evidence shows that approximately three in five women experienced physical and/or sexual violence by an intimate partner. However, across the globe, women and girls with impairments or life-limiting illnesses are more susceptible to different forms of violence across a range of environments and by different perpetrators including professionals and family members as well as partners. However, they are likely to be seriously disadvantaged in gaining information and support to escape the abusive relationships. This article stems from the United Kingdom part of a comparative study with three other countries (Austria, Germany, and Iceland) funded by the European Commission (EC; 2013-2015). It presents preliminary findings, generated from life history interviews, about disabled women's experiences of violence and access to support (both formal and informal) over their life course and their aspirations for the prevention of violence in the future. The article includes examples of impairment-specific violence that non-disabled women do not experience. By bringing the voices of disabled women into the public domain, the article will facilitate a historically marginalized group to contribute to the debate about disability, violence, and support

A roadmap for gene functional characterisation in wheat

To adapt to the challenges of climate change and the growing world population, it is vital to increase global crop production. Understanding the function of genes within staple crops will accelerate crop improvement by allowing targeted breeding approaches. Despite the importance of wheat, which provides 20 % of the calories consumed by humankind, a lack of genomic information and resources has hindered the functional characterisation of genes in this species. The recent release of a high-quality reference sequence for wheat underpins a suite of genetic and genomic resources that support basic research and breeding. These include accurate gene model annotations, gene expression atlases and gene networks that provide background information about putative gene function. In parallel, sequenced mutation populations, improved transformation protocols and structured natural populations provide rapid methods to study gene function directly. We highlight a case study exemplifying how to integrate these resources to study gene function in wheat and thereby accelerate improvement in this important crop. We hope that this review provides a helpful guide for plant scientists, especially those expanding into wheat research for the first time, to capitalise on the discoveries made in Arabidopsis and other plants. This will accelerate the improvement of wheat, a complex polyploid crop, of vital importance for food and nutrition security

Evolutionary relationships among barley and <i>Arabidopsis</i> core circadian clock and clock-associated genes

The circadian clock regulates a multitude of plant developmental and metabolic processes. In crop species, it contributes significantly to plant performance and productivity and to the adaptation and geographical range over which crops can be grown. To understand the clock in barley and how it relates to the components in the Arabidopsis thaliana clock, we have performed a systematic analysis of core circadian clock and clock-associated genes in barley, Arabidopsis and another eight species including tomato, potato, a range of monocotyledonous species and the moss, Physcomitrella patens. We have identified orthologues and paralogues of Arabidopsis genes which are conserved in all species, monocot/dicot differences, species-specific differences and variation in gene copy number (e.g. gene duplications among the various species). We propose that the common ancestor of barley and Arabidopsis had two-thirds of the key clock components identified in Arabidopsis prior to the separation of the monocot/dicot groups. After this separation, multiple independent gene duplication events took place in both monocot and dicot ancestors. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00239-015-9665-0) contains supplementary material, which is available to authorized users

Identification of Fusarium head blight resistance loci in two Brazilian wheat mapping populations.

Abstract Fusarium head blight (FHB) is a disease of wheat (Triticum aestivum L.) that causes major yield losses in South America, as well as many other wheat growing regions around the world. FHB results in low quality, contaminated grain due to the production of mycotoxins such as deoxynivalenol (DON). In Brazil, FHB outbreaks are increasing in frequency and are currently controlled by fungicides which are costly and potentially harmful to the wider environment. To identify the genetic basis of resistance to FHB in Brazilian wheat, two mapping populations (Anahuac 75 × BR 18-Terena and BR 18-Terena × BRS 179) segregating for FHB resistance were phenotyped and quantitative trait loci (QTL) analysis was undertaken to identify genomic regions associated with FHB-related traits. A total of 14 QTL associated with FHB visual symptoms were identified, each of which explained 3.7?17.3% of the phenotypic variance. Two of these QTL were stable across environments. This suggests FHB resistance in Anahuac 75, BR 18-Terena and BRS 179 is controlled by multiple genetic loci that confer relatively minor differences in resistance. A major, novel QTL associated with DON accumulation was also identified on chromosome 4B (17.8% of the phenotypic variance), as well as a major QTL associated with thousand-grain weight on chromosome 6B (16.8% phenotypic variance). These QTL could be useful breeding targets, when pyramided with major sources of resistance such as Fhb1, to improve grain quality and reduce the reliance on fungicides in Brazil and other countries affected by FHB