Characterization of the bacterioplankton communities in the melt-water ponds of Bratina Island, Victoria Land, Antarctica

Antarctic ecosystems (such as the ponds by Bratina Island, Antarctica) provide an excellent opportunity to examine organisms that can live in one of the most extreme and geochemically varied environments in the world. These ponds are of interest as each one can vary greatly in size, depth, and age as well as profiles of dissolved oxygen, metal concentrations, pH and salinity. Even within ponds geochemically distinct stratified layers can form which can greatly influence their microbial communities. There are a number of studies which indicate that microbial populations found in Antarctic ponds will be highly diverse and variable due to the uniqueness of the environment. This study aims to increase our knowledge of microbial biodiversity and the environmental factors which structure them, in particular the stratification transition zones within ponds water columns. A thorough set of biological samples were taken from five selected ponds during mid-summer in the 09-10 season to complement those taken during the winter freeze-up in the 07-08 extended season by Hawes and co-workers. Oxygen concentration, pH, conductivity and temperature of each pond water sample were measured in the field and water samples were taken back to the University of Waikato for further analysis. This research primarily used the DNA fingerprinting technique ARISA, matched with geochemistry to identify and characterise the resident and functional members of the microbial community and understand how the community is structured in relation to environmental conditions. We found that the planktonic populations of the Bratina Island ponds do vary between ponds, that each pond has its own chemical signature and that populations do change with depth. One of the studied ponds, Egg, was found to have an extreme chemical stratification leading to significantly different populations at each depth. Data analysis using BEST analysis determined that the changes in the bacterial populations in Egg are primarily in relation to the pH and conductivity at each depth which changes dramatically in the lower depths

Geochemical, Spatial, and Temporal Drivers of Microbial Community Heterogeneity in the Meltwater Ponds of Antarctica

Antarctic meltwater ponds are an abundant, dynamic and sensitive yet poorly understood ecosystem. In this thesis, bacterial communities from surface waters, the water column and benthic zone in geochemically variable meltwater ponds in the Ross Sea Region of Antarctica were investigated. The primary objective of this research was to provide a detailed description of the community composition and to determine the temporal, geochemical and geomorphological drivers of community structure. A coordinated comparable analysis method was used for all samples so that, although separated into the previously mentioned zones, findings could be directly compared across studies. Bacterial community structure between samples was initially investigated by Automated Ribosomal Intergenic Spacer Analysis (ARISA) of the 16S rRNA gene which, combined with in-situ collected geochemistry data was used to identify trends requiring high throughput sequencing (454 pyrosequencing of the V5-V6 hypervariable region of the 16S rRNA gene) analysis coupled with nutrient and elemental data. A preliminary study in December 2009 compared the water columns of five geochemically distinct ponds. Communities between ponds were distinct, their structure driven primarily by pH and conductivity. One geochemically stratified pond formed distinct surface and bottom clusters with increasing diversity and changes to phyla structure with depth. Temporal and geomorphological (Bratina Island and Miers Valley) drivers of variation in the microbial community structure between the surface waters of 41 ponds were examined. Conductivity was identified as the most significant driver across all ponds for the dominant cosmopolitan community, however trace elements were more significant drivers of community structure for the unique community (those sequences absent in at least one pond). Pronounced variation was identified between December and January samples and although the bacterial components of the community were similar between January 2012 and 2013 the community structure varied significantly. Despite different environments, communities from the Miers Valley were not well differentiated from Bratina Island, suggesting biological exchange between locations. The stratified water column of six Bratina Island and two Miers Valley ponds was investigated. Strongly geochemically stratified ponds exhibited a heterogeneous vertical community structure related to conductivity and dissolved oxygen. Variation in community structure was primarily driven by the abundance of a small number of cosmopolitan OTUs that changed with depth. Although the biological constituents were the same, minor variation in community structure was identified within Huey pond between years (2012 and 2013). Variation between Huey pond (Bratina Island) and Morepork pond (Miers Valley) was correlated with variation of iron and mercury concentration. Lastly the benthic zone of six ponds from Bratina Island and six from the Miers Valley was examined. The community structure was highly heterogeneous and diverse with 21 phyla identified. No distinction was identified between the two locations with the majority of pyrosequencing reads shared. Potassium, sodium and cobalt were identified as the most significant explanatory variables to the cosmopolitan community and aluminium, uranium and magnesium to the unique community. This study has granted an unprecedented understanding of the bacterial communities in the meltwater ponds of the Ross Sea Region. Geochemical inter pond heterogeneity is matched with an equally heterogeneous bacterial communities, primarily driven by conductivity. Although harboring a complex and diverse community the majority is comprised of a small number of shared OTUs across spatial and temporal scales

Characterisation of bacterioplankton communities in the meltwater ponds of Bratina Island, Victoria Land, Antarctica

A unique collection of Antarctic aquatic environments (meltwater ponds) lies in close proximity on the rock and sediment-covered undulating surface of the McMurdo Ice Shelf, near Bratina Island (Victoria Land, Antarctica). During the 2009–10 mid-austral summer, sets of discrete water samples were collected across the vertical geochemical gradients of five meltwater ponds (Egg, P70E, Legin, Salt and Orange) for geochemical and microbial community structure analysis. Bacterial DNA fingerprints (using Automated Ribosomal Intergenic Spacer Analysis) statistically clustered communities within ponds based on ANOSIM (R = 0.766, P = 0.001); however, one highly stratified pond (Egg) had two distinct depth-related bacterial communities (R = 0.975, P = 0.008). 454 pyrosequencing at three depths within Egg also identified phylum level shifts and increased diversity with depth, Bacteroidetes being the dominant phyla in the surface sample and Proteobacteria being dominant in the bottom two depths. BEST analysis, which attempts to link community structure and the geochemistry of a pond, identified conductivity and pH individually, and to a lesser extent Ag109, NO2 and V51 as dominant influences to the microbial community structure in these ponds. Increasing abundances of major halo-tolerant OTUs across the strong conductivity gradient reinforce it as the primary driver of community structure in this stud

Benthic microbial communities of coastal terrestrial and ice shelf Antarctic meltwater ponds.

The numerous perennial meltwater ponds distributed throughout Antarctica represent diverse and productive ecosystems central to the ecological functioning of the surrounding ultra oligotrophic environment. The dominant taxa in the pond benthic communities have been well described however, little is known regarding their regional dispersal and local drivers to community structure. The benthic microbial communities of 12 meltwater ponds in the McMurdo Sound of Antarctica were investigated to examine variation between pond microbial communities and their biogeography. Geochemically comparable but geomorphologically distinct ponds were selected from Bratina Island (ice shelf) and Miers Valley (terrestrial) (<40 km between study sites), and community structure within ponds was compared using DNA fingerprinting and pyrosequencing of 16S rRNA gene amplicons. More than 85% of total sequence reads were shared between pooled benthic communities at different locations (OTU0.05), which in combination with favorable prevailing winds suggests aeolian regional distribution. Consistent with previous findings Proteobacteria and Bacteroidetes were the dominant phyla representing over 50% of total sequences; however, a large number of other phyla (21) were also detected in this ecosystem. Although dominant Bacteria were ubiquitous between ponds, site and local selection resulted in heterogeneous community structures and with more than 45% of diversity being pond specific. Potassium was identified as the most significant contributing factor to the cosmopolitan community structure and aluminum to the location unique community based on a BEST analysis (Spearman's correlation coefficient of 0.632 and 0.806, respectively). These results indicate that the microbial communities in meltwater ponds are easily dispersed regionally and that the local geochemical environment drives the ponds community structure

Crop Updates - 2003 Weeds

This session covers Thirty four papers from different authors INTRODUCTION INTEGRATED WEED MANAGEMENT IWM system studies/demonstration sites Six years of IWM investigation – what does it tell us? Bill Roy, Agricultural Consulting and Research Services Pty Ltd Long term herbicide resistance site, the final chapter, Peter Newman and Glen Adam, Department of Agriculture Management of skeleton weed (chondrilla juncea) in a cropping rotation in Western Australia, J. R. Peirce and B. J. Rayner, Department of Agriculture WEED BIOLOGY AND COMPETITION Annual ryegrass seedbanks: The good, the bad and the ugly, Kathryn J. Steadman1, Amanda J. Ellery2 and Sally C. Peltzer3 , 1WA Herbicide Resistance Initiative, UWA, 2CSIRO Plant Industry, 3 Department of Agriculture Annual ryegrass seeds after-ripen faster during a hot summer, Kathryn J. Steadman1, Gavin P. Bignell1 and Amanda J. Ellery2, 1WA Herbicide Resistance Initiative, UWA, 2CSIRO Plant Industry Predicting annual ryegrass dormancy from climatic variables, Amanda Ellery, Andrew Moore, Sandy Nedelkos, Ross Chapman, CSIRO Plant Industry Removing dormancy in annual ryegrass seeds for early herbicide resistance testing, Kathryn J. Steadman and Mechelle J. Owen, WA Herbicide Resistance Initiative, UWA Annual ryegrass germination responds to nitrogen, Amanda Ellery1, Simone Dudley1 and Robert Gallagher2, 1CSIRO Plant Industry, 2Washington State University The agro-ecology of Malva parviflora (small flowered mallow), Pippa J. Michael, Kathryn J. Steadman and Julie A. Plummer, Western Australia Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia The looming threat of wild radish, Peter Newman, Department of Agriculture IWM TOOLS Double knock, how close can we go? Peter Newman and Glen Adam, Department of Agriculture Double knock herbicide effect on annual ryegrass, Catherine Borger, Abul Hashem and Nerys Wilkins, Department of Agriculture Tactical techniques for managing Annual Ryegrass, Sally Peltzer1, Alex Douglas1, Fran Hoyle1, Paul Matson1 and Michael Walsh2 Department of Agriculture and 2Western Australian Herbicide Resistance Initiative. Weed control through soil inversion, Sally Peltzer, Alex Douglas and Paul Matson, Department of Agriculture The burning issues of annual ryegrass seed control, Darren Chitty and Michael Walsh, Western Australian Herbicide Resistance Initiative, UWA No sign of chaff-cart resistant ryegrass! David Ferris, WA Herbicide Resistance Initiative UWA PACKAGES AND MODELLING Conserving glyphosate susceptibility – modelling past, present and future us. Paul Neve1, Art Diggle2, Patrick Smith3 and Stephen Powles1 ,1Western Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, 2Department of Agriculture, 3CSIRO Sustainable Ecosystems WEEDEM: A program for predicting weed emergence in Western Australia, Michael Walsh,1 David Archer2, James Eklund2 and Frank Forcella2, 1Western Australia Herbicide Resistance Initiative, UWA, 2USDA-Agricultural Research Service, 803 Iowa Avenue, Morris, MN 56267, USA Weed and herbicide management for long term profit: A workshop, Alister Draper1 and Rick Llewellyn12, 1WA Herbicide Resistance Initiative, 2School of Agricultural and Resource Economics, University of Western Australia HERBICIDE RESISTANCE Alternative herbicides for control of triazine and diflufenican multiple resistant wild radish, Aik Cheam1, Siew Lee1, David Nicholson1 and Mike Clarke2 1Department of Agriculture, Western Australia, 2Bayer CropScience Resistance of wild mustard biotype to ALS-inhibiting herbicides in WA Wheatbelt, Abul Hashem, Department of Agriculture Glyphosate-resistant ryegrass biotypes in the WA wheatbelt, Abul Hashem, Catherine Borger and Nerys Wilkins, Department of Agriculture Implications of herbicide rates for resistance management, Paul Neve, Western Australian Herbicide Resistance Initiative, University of Western Australia Putting a price on herbicide resistance, Rick Llewellyn, School of Agricultural and Resource Economics/WA Herbicide Resistance Initiative, University of Western Australia Herbicide resistance from over the fence: Mobility and management, Debbie Allena, Rick Llewellynb, aUniversity of Western Australia, 4th year student, 2002. Mingenew-Irwin Group, bSchool of Agricultural and Resource Economics/Western Australia Herbicide Resistance Initiative, University of Western Australia HERBICIDE TOLERANCE Herbicide tolerance of new barley varieties, Harmohinder S. Dhammu and Terry Piper, Department of Agriculture Herbicide tolerance of new lupins, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Department of Agriculture Herbicide tolerance of new field pea varieties, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Department of Agriculture Herbicide tolerance of new lentil varieties, H.S. Dhammu, T.J. Piper and L.E. Young, Department of Agriculture HERBICIDES – NEW PRODUCTS/PRODUCT USES; USE Kill half leaf ryegrass with Spray.Seed® at night, Peter Newman and Glenn Adam, Department of Agriculture CLEARFIELD™ wheat to control hard-to-kill weeds, Abul Hashem, Catherine Borger and Nerys Wilkins, Department of Agriculture Diuron, a possible alternative to simazine pre-emergent in lupins, Peter Newman and Glenn Adam, Department of Agriculture Dual Gold® soft on barley, soft on weeds in dry conditions, Peter Newman and Glenn Adam, Department of Agriculture Dual Gold® soft on lupins, soft on ryegrass in dry conditions, Peter Newman and Glenn Adam, Department of Agricultur

Sequencing of \u3ci\u3eAspergillus nidulans\u3c/i\u3e and comparative analysis with \u3ci\u3eA. fumigatus\u3c/i\u3e and \u3ci\u3eA. oryzae\u3c/i\u3e

The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso, and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation. Document includes all supplementary information (820 pages). Supplementary files are also attached below as Related files. THERE IS NO SUPPLEMENTARY FILE #7. PDF file size (with supplementary files included) is 10 Mbytes. An optimized version of the ARTICLE ONLY is attached as a Related File and is 1.9 Mbytes

Sequencing of \u3ci\u3eAspergillus nidulans\u3c/i\u3e and comparative analysis with \u3ci\u3eA. fumigatus\u3c/i\u3e and \u3ci\u3eA. oryzae\u3c/i\u3e

The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso, and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation. Document includes all supplementary information (820 pages). Supplementary files are also attached below as Related files. THERE IS NO SUPPLEMENTARY FILE #7. PDF file size (with supplementary files included) is 10 Mbytes. An optimized version of the ARTICLE ONLY is attached as a Related File and is 1.9 Mbytes

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist