Investigating the host range and origins of Phoma koolunga (Ascochyta blight of field pea)

Ascochyta blight (synonym: blackspot) is a serious, globally distributed, primarily foliar disease of Pisum sativum L. (field pea). It is typically caused by a combination of three or four fungal species that can exist independently of each other, called a complex. Phoma koolunga, identified in 2009 in South Australia, is the most recent addition in the Ascochyta complex. Despite multiple international studies on Ascochyta blight of field pea, P. koolunga has not been reported anywhere else in the world and the origins of the pathogen, and if it occurs on other legume species remain unknown. This study provides new information on the host range of P. koolunga on leguminous plants in controlled growth room conditions. To establish a host range, disease incidence and severity were assessed on 41 legume species comprising Australian native, weed, crop, pasture legumes and wild type Pisum, Lathyrus and Vicia species, following inoculation using two isolates of P. koolunga. All legumes tested, except Cicer arietinum (chickpea), developed leaf lesions and some also had stem and tendril lesions. Incidence and severity differed significantly among species but not consistently between isolates. The ability of the P. koolunga isolates to cause lesions on a wide range of legumes, including natives, in controlled environment conditions, suggests that it has a broad host range in humid and mild temperature conditions conducive for disease. Although all 17 native species developed some degree of leaf spotting, seven were considered susceptible because disease incidence was greater than 55 percent. This research also details the isolation, identification and classification of Didymellaceae fungi causing leaf spots, collected from legumes during field studies undertaken to investigate a possible native origin of P. koolunga. Samples from plants with leaf spots were collected from field pea growing regions throughout New South Wales, South Australia and Victoria taken back to the laboratory and cultured. The resultant fungal isolates were identified based on both morphology and phylogenetic analyses of the internal transcribed spacer region and part of the RNA polymerase II subunit B gene region. P. koolunga was not detected on native, weed or pasture legumes that had leaf spot symptoms in any of the regions visited, and only one isolate was recovered from field pea in the entire 2-year collection period. However, six novel species from the family Didymellaceae were isolated from Australian native legumes, five were from South Australia and one from New South Wales. The locations are represented by four different Australian Indigenous Peoples native language groups. Representatives of those groups were approached to request permission to use a suitable Aboriginal word for species epithet and permissions granted. These fungi are described here as Didymella djirangnandiri from Swainsona galegifolia, Didymella kaurna from Gastrolobium celsianum, Neodidymelliopsis tinkyukuku from Hardenbergia violaceae, Nothophoma garlbiwalawarda from Senna artemisioides, Nothophoma naiawu, and Nothophoma ngayawang also from S. artemisioides. Additional findings from the field collections were the identification of three new host-pathogen associations for Australia. Didymella pinodes, the primary pathogen responsible for Ascochyta blight of field pea, was isolated from leaf spots on naturalised species Vicia cracca (tufted vetch) in New South Wales and on Senna artemisioides from five different locations across South Australia. The discovery that these legumes may serve as an inoculum reservoir hosts for D. pinodes has implications for epidemiology and management of Ascochyta blight of field pea because both commonly occur in field pea growing regions throughout South Australia. Didymella lethalis was isolated from naturalised species, Lathyrus tingitanus (tangier pea), growing in a creek bed located in a well-used recreation area in Adelaide, South Australia. Phylogenetic analyses indicated that P. koolunga has a close relationship with the recently named species Ascochyta boeremae and supports the re-naming of P. koolunga as Ascochyta. Confirmation of the correction in nomenclature to Ascochyta koolunga comb. nov. was achieved with PCR followed by sequencing at two additional loci, the partial gene regions of ß-tubulin and the partial large subunit nrDNA (LSU). In summary, the controlled growth room results revealing a wide legume host range, and field collection results yielding no isolations from legumes other than field pea, suggest that P. koolunga is unlikely to have originated as a pathogen of Australian native legumes and provides no evidence regarding possible origins.Thesis (MPhil) -- University of Adelaide, School of Agriculture, Food and Wine, 202

Large-sample hydrology: recent progress, guidelines for new datasets and grand challenges

Large-sample hydrology (LSH) relies on data from large sets (tens to thousands) of catchments to go beyond individual case studies and derive robust conclusions on hydrological processes and models. Numerous LSH datasets have recently been released, covering a wide range of regions and relying on increasingly diverse data sources to characterize catchment behaviour. These datasets offer novel opportunities, yet they are also limited by their lack of comparability, uncertainty estimates and characterization of human impacts. This article (i) underscores the key role of LSH datasets in hydrological studies, (ii) provides a review of currently available LSH datasets, (iii) highlights current limitations of LSH datasets and (iv) proposes guidelines and coordinated actions to overcome these limitations. These guidelines and actions aim to standardize and automatize the creation of LSH datasets worldwide, and to enhance the reproducibility and comparability of hydrological studies

Note and Comment

The Tight of a Trade Union to Enforce a Boycott; Criminal Responsibility of Husband for Maliciously Slandering His Wife; The Bulk Sales Laws; The Police Power and Liberty of Contract; The Obligations Resulting from an Indorsement, In Blank, Before Delivery, of a Negotiable Instrumen

Cryptic diversity found in Didymellaceae from Australian native legumes

Ascochyta koolunga (Didymellaceae, Pleosporales) was first described in 2009 (as Phoma koolunga) and identified as the causal agent of Ascochyta blight of Pisum sativum (field pea) in South Australia. Since then A. koolunga has not been reported anywhere else in the world, and its origins and occurrence on other legume (Fabaceae) species remains unknown. Blight and leaf spot diseases of Australian native, pasture and naturalised legumes were studied to investigate a possible native origin of A. koolunga. Ascochyta koolunga was not detected on native, naturalised or pasture legumes that had leaf spot symptoms, in any of the studied regions in southern Australia, and only one isolate was recovered from P. sativum. However, we isolated five novel species in the Didymellaceae from leaf spots of Australian native legumes from commercial field pea regions throughout southern Australia. The novel species were classified on the basis of morphology and phylogenetic analyses of the internal transcribed spacer region and part of the RNA polymerase II subunit B gene region. Three of these species, Nothophoma garlbiwalawarda sp. nov., Nothophoma naiawu sp. nov. and Nothophoma ngayawang sp. nov., were isolated from Senna artemisioides. The other species described here are Epicoccum djirangnandiri sp. nov. from Swainsona galegifolia and Neodidymelliopsis tinkyukuku sp. nov. from Hardenbergia violacea. In addition, we report three new host-pathogen associations in Australia, namely Didymella pinodes on S. artemisioides and Vicia cracca, and D. lethalis on Lathyrus tingitanus. This is also the first report of Didymella prosopidis in Australi

Retinal Expression of Wnt-Pathway Mediated Genes in Low-Density Lipoprotein Receptor-Related Protein 5 (Lrp5) Knockout Mice

Mutations in low-density lipoprotein receptor-related protein 5 (Lrp5) impair retinal angiogenesis in patients with familial exudative vitreoretinopathy (FEVR), a rare type of blinding vascular eye disease. The defective retinal vasculature phenotype in human FEVR patients is recapitulated in Lrp5 knockout $(Lrp5^{-/-})$ mouse with delayed and incomplete development of retinal vessels. In this study we examined gene expression changes in the developing $Lrp5^{−/−}$ mouse retina to gain insight into the molecular mechanisms that underlie the pathology of FEVR in humans. Gene expression levels were assessed with an Illumina microarray on total RNA from $Lrp5^{−/−}$ and WT retinas isolated on postnatal day (P) 8. Regulated genes were confirmed using RT-qPCR analysis. Consistent with a role in vascular development, we identified expression changes in genes involved in cell-cell adhesion, blood vessel morphogenesis and membrane transport in $Lrp5^{−/−}$ retina compared to WT retina. In particular, tight junction protein claudin5 and amino acid transporter slc38a5 are both highly down-regulated in $Lrp5^{−/−}$ retina. Similarly, several Wnt ligands including Wnt7b show decreased expression levels. Plasmalemma vesicle associated protein (plvap), an endothelial permeability marker, in contrast, is up-regulated consistent with increased permeability in $Lrp5^{−/−}$ retinas. Together these data suggest that Lrp5 regulates multiple groups of genes that influence retinal angiogenesis and may contribute to the pathogenesis of FEVR

Modular Assessment of Rainfall-Runoff Models Toolbox (MARRMoT) v1.2:an open-source, extendable framework providing implementations of 46 conceptual hydrologic models as continuous state-space formulations

This paper presents the Modular Assessment of Rainfall-Runoff Models Toolbox (MARRMoT): A modular open-source toolbox containing documentation and model code based on 46 existing conceptual hydrologic models. The toolbox is developed in MATLAB and works with Octave. MARRMoT models are based solely on traceable published material and model documentation, not on already-existing computer code. Models are implemented following several good practices of model development: The definition of model equations (the mathematical model) is kept separate from the numerical methods used to solve these equations (the numerical model) to generate clean code that is easy to adjust and debug; the implicit Euler time-stepping scheme is provided as the default option to numerically approximate each model's ordinary differential equations in a more robust way than (common) explicit schemes would; threshold equations are smoothed to avoid discontinuities in the model's objective function space; and the model equations are solved simultaneously, avoiding the physically unrealistic sequential solving of fluxes. Generalized parameter ranges are provided to assist with model inter-comparison studies. In addition to this paper and its Supplement, a user manual is provided together with several workflow scripts that show basic example applications of the toolbox. The toolbox and user manual are available from span classCombining double low line"uri"https://github.com/wknoben/MARRMoT/span (last access: 30 May 2019; a hrefCombining double low line"https://doi.org/10.5281/zenodo.3235664"https://doi.org/10.5281/zenodo.3235664). Our main scientific objective in developing this toolbox is to facilitate the inter-comparison of conceptual hydrological model structures which are in widespread use in order to ultimately reduce the uncertainty in model structure selection

Simulating Runoff Under Changing Climatic Conditions:A Framework for Model Improvement

Rainfall-runoff models are often deficient under changing climatic conditions, yet almost no recent studies propose new or improved model structures, instead focusing on model intercomparison, input sensitivity, and/or quantification of uncertainty. This paucity of progress in model development is (in part) due to the difficulty of distinguishing which cases of model failure are truly caused by structural inadequacy. Here we propose a new framework to diagnose the salient cause of poor model performance in changing climate conditions, be it structural inadequacy, poor parameterization, or data errors. The framework can be applied to a single catchment, although larger samples of catchments are helpful to generalize and/or cross-check results. To generate a diagnosis, multiple historic periods with contrasting climate are defined, and the limits of model robustness and flexibility are explored over each period separately and for all periods together. Numerous data-based checks also supplement the results. Using a case study catchment from Australia, improved inference of structural failure and clearer evaluation of model structural improvements are demonstrated. This framework enables future studies to (i) identify cases where poor simulations are due to poor calibration methods or data errors, remediating these cases without recourse to structural changes; and (ii) use the remaining cases to gain greater clarity into what structural changes are needed to improve model performance in changing climate

How Irish design consultancies align with Ireland’s Innovation 2020 priorities: a preliminary study

peer-reviewedThe Government of Ireland has positioned design as integral to the innovation landscape. In particular, it encourages innovations from designers that align with six thematic areas identified in the Innovation 2020 report. Those areas are health & medical, information & technology communications (ITC), food, energy, manufacturing & materials and service & business processes. However, research is yet to show the current contribution of design consultancies and their project outcomes categorised within these six priority thematic areas. This paper presents empirical findings on a review of 571 projects advertised on the websites of 26 design consultancies in Ireland. It shows that just under half of the reviewed design projects fall within the thematic project areas. Furthermore, this paper shows the differences between three design disciplines (product design, user-experience design and branding design) and their contribution of projects to each thematic area. The results of this empirical study are relevant and of use to design practitioners, clients and policy makers. For designers, this research identifies opportunities for new business and innovation within the Government of Ireland key thematic areas. For design clients, this research offers opportunities to seek input from relevant design disciplines according to the thematic alignment of their project. For policy makers, this research offers context of the six key thematic areas within the design disciplines in Ireland. Lastly, the results of this research suggest that across the disciplines of product, user-experience and branding design, preferred priority themes are evident

Australian non-perennial rivers: Global lessons and research opportunities

Non-perennial rivers are valuable water resources that support millions of humans globally, as well as unique riparian ecosystems. In Australia, the Earth’s driest inhabited continent, over 70% of rivers are non-perennial due to a combination of ancient landscape, dry climates, highly variable rainfall regimes, and human interventions that have altered riverine environments. Here, we review Australian non-perennial river research incorporating geomorphology, hydrology, biogeochemistry, ecology, and Indigenous knowledges. The dominant research themes in Australia were drought, floods, salinity, dryland ecology, and water management. Future research will likely follow these themes but must address emerging threats to river systems due to climate change and other anthropogenic impacts. Four high level opportunities for future research are identified, namely: (1) integrating Indigenous and western scientific knowledge; (2) quantifying climate change impacts on hydrological and biological function; (3) clarifying the meaning and measurement of “restoration” of non-perennial systems; and (4) understanding the role of groundwater. These challenges will require inter- and multi-disciplinary efforts supported by technological advances. The evolving body of knowledge about Australian rivers provides a foundation for comparison with other dryland areas globally where recognition of the importance of non-perennial rivers is expanding