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Ascochyta lentis, the causal organism of ascochyta blight of lentil (Lens culinaris L.), has been shown to produce an avirulence effector protein that mediates ascochyta blight (AB) resistance in certain lentil cultivars. The two known forms of the effector protein were identified from a biparental mapping population between isolates that have reciprocal virulence on PBA Hurricane XT and Nipper. The effector AlAvr1–1 was described for the PBA Hurricane XT–avirulent isolate P94–24 and AlAvr1–2 characterised in the PBA Hurricane XT-virulent isolate AlKewell. Here, we performed a genome-wide association study (GWAS) to identify other loci associated with AB for a differential set of lentil cultivars from a diverse panel of isolates collected in the Australian lentil growing regions from 2013 to 2020. The chromosome 3 AlAvr1 locus was strongly associated with the PBA Hurricane XT, Indianhead and Nipper disease responses but one other genomic region on chromosome 11 was also associated with the Nipper disease trait. Our results corroborate the earlier work that identified the AlAvr1 locus, for field-collected isolates that span the period prior to release and after widespread adoption of PBA Hurricane XT. A multiplex PCR assay was developed to differentiate the respective genes AlAvr1–1 and AlAvr1–2, to predict PBA Hurricane XT avirulence and pathotype designation in the diversity panel. Increasing numbers of the PBA Hurricane XT–virulent pathotype 2 isolates across that time indicates strong selection for isolates with the AlAvr1–2 allele. Furthermore, one other region of the A. lentis genome may contribute to the pathogen-host interaction for lentil AB.

Lentil (Lens culinaris Medik.) is a self-pollinating, diploid, annual, cool-season, food legume crop that is cultivated throughout the world. Ascochyta blight (AB), caused by Ascochyta lentis Vassilievsky, is an economically important and widespread disease of lentil. Development of cultivars with high levels of durable resistance provides an environmentally acceptable and economically feasible method for AB control. A detailed understanding of the genetic basis of AB resistance is hence highly desirable, in order to obtain insight into the number and influence of resistance genes. Genetic linkage maps based on single nucleotide polymorphisms (SNP) and simple sequence repeat (SSR) markers have been developed from three recombinant inbred line (RIL) populations. The IH × NF map contained 460 loci across 1461.6 cM, while the IH × DIG map contained 329 loci across 1302.5 cM and the third map, NF × DIG contained 330 loci across 1914.1 cM. Data from these maps were combined with a map from a previously published study through use of bridging markers to generate a consensus linkage map containing 689 loci distributed across seven linkage groups (LGs), with a cumulative length of 2429.61 cM at an average density of one marker per 3.5 cM. Trait dissection of AB resistance was performed for the RIL populations, identifying totals of two and three quantitative trait loci (QTLs) explaining 52 and 69% of phenotypic variation for resistance to infection in the IH × DIG and IH × NF populations, respectively. Presence of common markers in the vicinity of the AB_IH1- and AB_IH2.1/AB_IH2.2-containing regions on both maps supports the inference that a common genomic region is responsible for conferring resistance and is associated with the resistant parent, Indianhead. The third QTL was derived from Northfield. Evaluation of markers associated with AB resistance across a diverse lentil germplasm panel revealed that the identity of alleles associated with AB_IH1 predicted the phenotypic responses with high levels of accuracy (~86%), and therefore have the potential to be widely adopted in lentil breeding programs. The availability of RIL-based maps, a consensus map, and validated markers linked to AB resistance provide important resources for lentil improvement.

Johnson is not commonly thought of as a historian, partly because his affinities led him to reject the secular and skeptical precepts of Enlightenment historiography. This chapter shows how historical thinking pervades Johnson’s writing, tracing concerns and beliefs about history that include the following: the relationship between oral and written testimony; the nature of historical evidence, including material evidence; and the value of considering history and life-writing, in the absence of written sources, as akin to ethnography. Drawing extensively on the Journey to the Western Islands of Scotland for Johnson’s most explicit reflections on historiography, all colored by a profound sense of loss, the chapter turns in conclusion to Johnson’s three major histories of language and literature: the Dictionary, the Shakespeare edition, and the Lives of the Poets.

Ascochyta blight disease, caused by the necrotrophic fungus Ascochyta rabiei, is a major biotic constraint to chickpea production in Australia and worldwide. Detailed knowledge of the structure of the pathogen population and its potential to adapt to our farming practices is key to informing optimal management of the disease. This includes understanding the molecular diversity among isolates and the frequency and distribution of the isolates that have adapted to overcome host resistance across agroecologically distinct regions. Thanks to continuous monitoring efforts over the past 6 years, a comprehensive collection of A. rabiei isolates was collated from the major Australian chickpea production regions. To determine the molecular structure of the entire population, representative isolates from each collection year and growing region have been genetically characterized using a DArTseq genotyping-by-sequencing approach. The genotyped isolates were further phenotyped to determine their pathogenicity levels against a differential set of chickpea cultivars and genotype-phenotype associations were inferred. Overall, the Australian A. rabiei population displayed a far lower genetic diversity (average Nei’s gene diversity of 0.047) than detected in other populations worldwide. This may be explained by the presence of a single mating-type in Australia, MAT1-2, limiting its reproduction to a clonal mode. Despite the low detected molecular diversity, clonal selection appears to have given rise to a subset of adapted isolates that are highly pathogenic on commonly employed resistance sources, and that are occurring at an increasing frequency. Among these, a cluster of genetically similar isolates was identified, with a higher proportion of highly aggressive isolates than in the general population. The discovery of distinct genetic clusters associated with high and low isolate pathogenicity forms the foundation for the development of a molecular pathotyping tool for the Australian A. rabiei population. Application of such a tool, along with continuous monitoring of the genetic structure of the population will provide crucial information for the screening of breeding material and integrated disease management packages.

Ascochyta blight disease, caused by the necrotrophic fungusAscochyta rabiei, is a major biotic constraint to chickpea production in Australia and worldwide. Detailed knowledge of the structure of the pathogen population and its potential to adapt to our farming practices is key to informing optimal management of the disease. This includes understanding the molecular diversity among isolates and the frequency and distribution of the isolates that have adapted to overcome host resistance across agro-geographically distinct regions.Thanks to continuous monitoring efforts over the past six years, a comprehensive collection ofA. rabieiisolates was collated from the major Australian production regions. To determine the molecular structure of the entire population, representative isolates from each collection year and growing region have been genetically characterised using a DArTseq™ genotyping-by-sequencing approach. The genotyped isolates were further phenotyped to determine their pathogenicity levels against a differential set of chickpea cultivars and genotype-phenotype associations were inferred.Overall, the AustralianA. rabieipopulation displayed a far lower genetic diversity (average Nei’s gene diversity of 0.047) than detected in other populations worldwide. This may be explained by the presence of a single mating-type in Australia, MAT1-2, limiting its reproduction to a clonal mode. Despite the low detected molecular diversity, clonal selection appears to have given rise to a subset of adapted isolates that are highly pathogenic on commonly employed resistance sources, and that are occurring at an increasing frequency.To better understand the mechanisms and patterns of the pathogen adaptation, multi-locus genotype analysis was performed and two hypotheses were proposed on how new genotypes emerge. These were: 1) In a local, within-region evolutionary pathway; or 2) Through inter-region dispersal, most likely due to human activities. Furthermore, a cluster of genetically similar isolates was identified, with a higher proportion of highly aggressive isolates than in the general population, indicating the adaptive evolution of a sub-set of isolates that pose a greater risk to the chickpea industry.The discovery of distinct genetic clusters associated with high and low isolate pathogenicity forms the foundation for the development of a molecular pathotyping tool for the AustralianA. rabieipopulation. Application of such a tool, along with continuous monitoring of the genetic structure of the population will provide crucial information for the screening of breeding material and integrated disease management packages.Data SummaryAn online dataset containing all supporting genotyping and phenotyping data and the code required to reproduce the results, summary tables and plots found in this publication, is publicly available at Zenodo via the following links:https://zenodo.org/record/4311477; DOI:10.5281/zenodo.4311477(1).

An assessment of recent scholarly work treating the literature of the Restoration and Eighteenth Century and some general observations on the state of the profession. A full bibliography and price list of works received by SEL for consideration follow.

This chapter explores the broad cultural transition from drama to novel during the Restoration period, which triggered one of the most productive periods in the history of the London stage. However, when it comes to the eighteenth century proper, the novel is more likely to be identified as the century's most significant and appealing popular genre. The chapter considers why the novel has largely superseded drama as the literary form to which ambitious and imaginative literary types without a strong affinity for verse writing would by default have turned their attention and energies by the middle of the eighteenth century. Something important may have been lost in the broad cultural transition from drama to novel. This chapter, however, contends that many things were preserved: that the novel was able to absorb many of the functions and techniques not just of Restoration comedy but of the theatre more generally.

For the first time, Cucumber mosaic virus (CMV), Pea seed-borne mosaic virus (PSbMV) and Turnip yellows virus (TuYV) were detected in a naturally infected fenugreek (Trigonella foenum-graecum) crop in Australia. The level of infection reached an alarming 90%, 75% and 20% respectively for CMV, TuYV and PSbMV, resulting in total crop loss. Both CMV and TuYV were detected in non-symptomatic fenugreek plants while PSbMV was not. Seed lots from the crop in question were established, planted in the glasshouse and tested for a range of seed-borne viruses, none of which were detected. Additionally, fenugreek seedlings grown from the seeds in the glasshouse were found to be readily infected with a TuYV isolate from canola when inoculated using viruliferous Myzus persicae.

This essay considers the interdependence of formal and ethical questions about the appropriate use of particular detail by juxtaposing eighteenth-century fiction to contemporary practices of life-writing, especially the use of detail by Johnson in his Lives of the Poets and Boswell in his Life of Johnson . After laying out some premises about what constitutes novelistic detail during this period, the essay explores a productive tension between an ethical argument against “being particular” when writing about real historical figures and an increasingly strong preference for specificity in both fiction and nonfiction.

Ascochyta blight (AB) is a fungal disease that can significantly reduce chickpea production in Australia and other regions of the world. In this study, 69 chickpea genotypes were sequenced using whole genome re-sequencing (WGRS) methods. They included 48 Australian varieties differing in their resistance ranking to AB, 16 advanced breeding lines from the Australian chickpea breeding program, four landraces, and one accession representing the wild chickpea species Cicer reticulatum. More than 800,000 single nucleotide polymorphisms (SNPs) were identified. Population structure analysis revealed relatively narrow genetic diversity amongst recently released Australian varieties and two groups of varieties separated by the level of AB resistance. Several regions of the chickpea genome were under positive selection based on Tajima’s D test. Both Fst genome- scan and genome-wide association studies (GWAS) identified a 100 kb region (AB4.1) on chromosome 4 that was significantly associated with AB resistance. The AB4.1 region co-located to a large QTL interval of 7 Mb∼30 Mb identified previously in three different mapping populations which were genotyped at relatively low density with SSR or SNP markers. The AB4.1 region was validated by GWAS in an additional collection of 132 advanced breeding lines from the Australian chickpea breeding program, genotyped with approximately 144,000 SNPs. The reduced level of nucleotide diversity and long extent of linkage disequilibrium also suggested the AB4.1 region may have gone through selective sweeps probably caused by selection of the AB resistance trait in breeding. In total, 12 predicted genes were located in the AB4.1 QTL region, including those annotated as: NBS-LRR receptor-like kinase, wall-associated kinase, zinc finger protein, and serine/threonine protein kinases. One significant SNP located in the conserved catalytic domain of a NBS-LRR receptor-like kinase led to amino acid substitution. Transcriptional analysis using qPCR showed that some predicted genes were significantly induced in resistant lines after inoculation compared to non-inoculated plants. This study demonstrates the power of combining WGRS data with relatively simple traits to rapidly develop “functional makers” for marker-assisted selection and genomic selection.

© 2016 by Emerald Group Publishing Limited. Purpose - Public entrepreneurship is increasingly being propounded as a key means of ‘doing more with less’ during the tough times associated with successive rounds of neoliberal restructuring and austerity. The primary aim of this chapter is to provide a critical-exploratory review of sponsorship - a disruptive interjection or particular form of public entrepreneurship. Methodology/approach - Public entrepreneurship provides a useful theoretical frame for exploring some emergent ways of delivering public services in a post-Credit Crunch global operating environment. Empirical insights are derived from a single local authority in the United Kingdom. Findings - There is a widespread concern that straitened economic conditions can engender the prevalence of short-term financial considerations at the expense of other objectives. Sponsorship, as a discrete form of public entrepreneurship in some circumstances has the potential to achieve multiple objectives, enriching public value. However, this is contingent of specific contextual factors. Practical implications - By identifying some risks associated with disruptive interjections intended to open new paths for the sponsorship of public services as well as indicating some opportunities for risk reduction, it is hoped that our analysis may benefit public authorities when they are exploring or evaluating sponsorship ‘opportunities’. Originality/value - Examining sponsorship through a public entrepreneurship conceptual frame has received limited research attention. Whether sponsorship is a ‘winning solution’ is contingent on the particular form of sponsorship as well as the specific time and place.

Chemotaxonomy and the comparative analysis of metabolic features of fungi have the potential to provide valuable information relating to ecology and evolution, but have not been fully explored in fungal biology. Here, we investigated the chemical diversity of legume-associated Ascochyta and Phoma species and the possible use of a metabolomics approach using liquid chromatography-mass spectrometry for their classification. The metabolic features of 45 strains including 11 known species isolated from various legumes were extracted and the datasets were analyzed using chemometrics methods such as principal component and hierarchical clustering analyses. We found a high degree of intra-species consistency in metabolic profiles, but inter-species diversity was high. Molecular phylogenies of the legume-associated Ascochyta/Phoma species were estimated using sequence data from three protein-coding genes and the five major chemical groups that were detected in the hierarchical clustering analysis were mapped to the phylogeny. Clusters based on similarity of metabolic features were largely congruent with the species phylogeny. These results indicated that evolutionarily distinct fungal lineages have diversified their metabolic capacities as they have evolved independently. This whole metabolomics approach may be an effective tool for chemotaxonomy of fungal taxa lacking information on their metabolic content.

International audience; Necrotrophic pathogens of the cool season food legumes (pea, lentil, chickpea, faba bean and lupin) cause wide spread disease and severe crop losses throughout the world. Environmental conditions play an important role in the development and spread of these diseases. Form of inoculum, inoculum concentration and physiological plant growth stage all affect the degree of infection and the amount of crop loss. Measures to control these diseases have relied on identification of resistant germplasm and development of resistant varieties through screening in the field and in controlled environments. Procedures for screening and scoring germplasm and breeding lines for resistance have lacked uniformity among the various programs worldwide. However, this review highlights the most consistent screening and scoring procedures that are simple to use and provide reliable results. Sources of resistance to the major necrotrophic fungi are summarized for each of the cool season food legumes. Marker-assisted selection is underway for Ascochyta blight of pea, lentil and chickpea, and Phomopsis blight of lupin. Other measures such as fungicidal control and cultural control are also reviewed. The emerging genomic information on the model legume, Medicago truncatula, which has various degrees of genetic synteny with the cool season food legumes, has promise for identification of closely linked markers for resistance genes and possibly for eventual map-based cloning of resistance genes. Durable resistance to the necrotrophic pathogens is a common goal of cool season food legume breeders