Assessment of Wild Mustard (Sinapis arvensis L.) Resistance to ALS-inhibiting Herbicides

There is an urgent need for rapid, accurate, and economical screening tests that can determine if weeds surviving a herbicide application are resistant. This chapter describes development and application of a simple root length bioassay technique for detection of wild mustard (Sinapis arvensis L.) resistance to ALS-inhibiting herbicides. This bioassay was performed in 2-oz WhirlPak® bags filled with 50 g of soil wetted to 100% moisture content at field capacity. Wild mustard seeds were pre-germinated in darkness in Petri dishes lined with moist filter paper for 2 days. Six seeds with well-developed radicles were planted in the non-treated soil and in soil with added herbicide, and plants were grown in a laboratory under fluorescent lights. After 4 days of growth, WhirlPak® bags were cut open, soil was washed away, intact plants were removed, and root length was measured with a ruler. The concentration of each herbicide in soil at which a significant root inhibition of susceptible biotype, but no root inhibition of a resistant biotype occurred was selected. Susceptibility/resistance of wild mustard populations was estimated by calculating the percentage of uninhibited roots of plants grown in the herbicide-treated soil as compared to the plants grown in the non-treated soil

Agricultural Weed Assessment Calculator: An Australian Evaluation

Weed risk assessment systems are used to estimate the potential weediness or invasiveness of introduced species in non-agricultural habitats. However, an equivalent system has not been developed for weed species that occur in agronomic cropland. Therefore, the Agricultural Weed Assessment Calculator (AWAC) was developed to quantify the present and potential future adverse impact of a weed species on crop production and profitability (threat analysis), thereby informing or directing research, development, and extension (RDE) investments or activities. AWAC comprises 10 questions related primarily to a weed’s abundance and economic impact. Twenty weed species from across Australia were evaluated by AWAC using existing information and expert opinion, and rated as high, medium, or low for RDE prioritization based on total scores of 70 to 100, 40 to <70, or <40, respectively. Five species were rated as high (e.g., Lolium rigidum Gaud.), eight were rated as medium (e.g., Conyza spp.), and seven were rated as low (e.g., Rapistrum rugosum L.). Scores were consistent with the current state of knowledge of the species’ impact on grain crop production in Australia. AWAC estimated the economic or agronomic threat of 20 major or minor agricultural weeds from across Australia. The next phase of development is the testing of AWAC by weed practitioners (e.g., agronomists, consultants, farmers) to verify its utility and robustness in accurately assessing these and additional weed species

Weed seedbank management and the infuence of seed predators

Non-Peer ReviewedIncreasing herbicide resistance has led weed scientists to focus on managing the weed seedbank. Indeed, seedbank management is critical and should be a priority for annual weeds. Post-emergence weed control should be seen as a rescue treatment and not as a first line of defence. But which weeds do we prioritize and what tactics can we use to manage the seedbank? This talk will shed light on weed species of priority for seedbank management, criteria to implement for managing the seedbank, and novel methods of seedbank management with a major emphasis on seed predators. Regardless of how producers try to manage weed seed shed, seeds will fall to the ground and thus we must develop ways to manage these seeds. Seed predators represent a major opportunity to help exhaust weed seeds from the seedbank

Herbicide-resistant weeds : from research and knowledge to future needs

Synthetic herbicides have been used globally to control weeds in major field crops. This has imposed a strong selection for any trait that enables plant populations to survive and reproduce in the presence of the herbicide. Herbicide resistance in weeds must be minimized because it is a major limiting factor to food security in global agriculture. This represents a huge challenge that will require great research efforts to develop control strategies as alternatives to the dominant and almost exclusive practice of weed control by herbicides. Weed scientists, plant ecologists and evolutionary biologists should join forces and work towards an improved and more integrated understanding of resistance across all scales. This approach will likely facilitate the design of innovative solutions to the global herbicide resistance challenge

Simulation models on the ecology and management of arableweeds: Structure, quantitative insights, and applications

In weed science and management, models are important and can be used to better understand what has occurred in management scenarios, to predict what will happen and to evaluate the outcomes of control methods. To-date, perspectives on and the understanding of weed models have been disjointed, especially in terms of how they have been applied to advance weed science and management. This paper presents a general overview of the nature and application of a full range of simulation models on the ecology, biology, and management of arable weeds, and how they have been used to provide insights and directions for decision making when long-term weed population trajectories are impractical to be determined using field experimentation. While research on weed biology and ecology has gained momentum over the past four decades, especially for species with high risk for herbicide resistance evolution, knowledge gaps still exist for several life cycle parameters for many agriculturally important weed species. More research efforts should be invested in filling these knowledge gaps, which will lead to better models and ultimately better inform weed management decision making.Fil: Bagavathiannan, Muthukumar V.. Texas A&M University; Estados UnidosFil: Beckie, Hugh J.. University of Western Australia; AustraliaFil: Chantre Balacca, Guillermo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: González Andujar, José L.. Consejo Superior de Investigaciones Científicas; EspañaFil: Leon, Ramon G.. North Carolina State University; Estados UnidosFil: Neve, Paul. Agriculture & Horticulture Development Board; Reino UnidoFil: Poggio, Santiago Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Schutte, Brian J.. New Mexico State University.; Estados UnidosFil: Somerville, Gayle J.. Sustainable Agriculture Sciences; Reino UnidoFil: Werle, Rodrigo. University of Wisconsin; Estados UnidosFil: Acker, Rene Van. University of Guelph; Canad

Considering weed management as a social dilemma bridges individual and collective interests

Weeds pose severe threats to agricultural and natural landscapes worldwide. One major reason for the failure to effectively manage weeds at landscape scales is that current Best Management Practice guidelines, and research on how to improve such guidelines, focus too narrowly on property-level management decisions. Insufficiently considered are the aggregate effects of individual actions to determine landscape-scale outcomes, or whether there are collective practices that would improve weed management outcomes. Here, we frame landscape-scale weed management as a social dilemma, where trade-offs occur between individual and collective interests. We apply a transdisciplinary system approach—integrating the perspectives of ecologists, evolutionary biologists and agronomists into a social science theory of social dilemmas—to four landscape-scale weed management challenges: (i) achieving plant biosecurity, (ii) preventing weed seed contamination, (iii) maintaining herbicide susceptibility and (iv) sustainably using biological control. We describe how these four challenges exhibit characteristics of ‘public good problems’, wherein effective weed management requires the active contributions of multiple actors, while benefits are not restricted to these contributors. Adequate solutions to address these public good challenges often involve a subset of the eight design principles developed by Elinor Ostrom for ‘common pool social dilemmas’, together with design principles that reflect the public good nature of the problems. This paper is a call to action for scholars and practitioners to broaden our conceptualization and approaches to weed management problems. Such progress begins by evaluating the public good characteristics of specific weed management challenges and applying context-specific design principles to realize successful and sustainable weed management

Crop Updates 2010 - Crop Specific

This session covers twenty four papers from different authors: PLENARY 1. Challenges facing western Canadian cropping over the next 10 years, Hugh J Beckie, Research Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan CROP SPECIFIC Breeding 2. The challenge of breeding canola hybrids – new opportunities for WA growers, Wallace Cowling, Research Director, Canola Breeders Western Australia Pty Ltd 3. Chickpea 2009 crop variety testing of germplasm developed by DAFWA/CLIMA/ICRISAT/COGGO alliance. Khan, TN1,3, Adhikari, K1,3, Siddique, K2, Garlinge, J1, Smith, L1, Morgan, S1 and Boyd, C1 1Department of Agriculture and Food, Western Australia (DAFWA), 2Insititute of Agriculture, The University of Western Australia (UWA), 3Centre for Legumes in Mediterranean Agriculture (CLIMA), The University of Western Australia 4. PBA Pulse Breeding Australia – 2009 Field Pea Results, Ian Pritchard1, Chris Veitch1, Colin Boyd1, Stuart Morgan1, Alan Harris1 and Tony Leonforte2, 1Department of Agriculture and Food, Western Australia, 2Department of Primary Industries, Victoria 5. PBA Pulse Breeding Australia – 2009 Chickpea Results, Ian Pritchard1, Chris Veitch1, Colin Boyd1, Murray Blyth1, Shari Dougal1 and Kristy Hobson2 1Department of Agriculture and Food, Western Australia, 2Department of Primary Industries, Victoria Decision Support 6. A tool for identifying problems in wheat paddocks, Ben Curtis and Doug Sawkins, Department of Agriculture and Food 7. DAFWA Seasonal Forecast for 2010, Stephens, D, Department of Agriculture and Food, Western Australian, Climate and Modelling Group Disease 8. Enhancement of black spot resistance in field pea, Kedar Adhikari, T Khan, S Morgan and C Boyd, Department of Agriculture and Food, 9. fungicide management of yellow spot in wheat, Ciara Beard, Kith Jayasena, Kazue Tanaka and Anne Smith, Department of Agriculture and Food 10. Resistance to infection by Beet western yellows virus in four Australian canola varieties, Brenda Coutts and Roger Jones, Department of Agriculture and Food 11. Yellow spot carryover risk from stubble in wheat-on-wheat rotations, Jean Galloway, Pip Payne and Tess Humphreys, Department of Agriculture and Food 12. Fungicides for the future: Management of Barley Powdery Mildew and Leaf Rust, Kith Jayasena, Kazue Tanaka and William MacLeod, Department of Agriculture and Food 13. 2009 canola disease survey and management options for blackleg and Sclerotinia in 2010, Ravjit Khangura, WJ MacLeod, M Aberra and H Mian, Department of Agriculture and Food 14. Impact of variety and fungicide on carryover of stubble borne inoculum and yellow spot severity in continuous wheat cropping, Geoff Thomas, Pip Payne, Tess Humphreys and Anne Smith, Department of Agriculture and Food 15. Limitations to the spread of Wheat streak mosaic virus by the Wheat curl mite in WA during 2009, Dusty Severtson, Peter Mangano, Brenda Coutts, Monica Kehoe and Roger Jones, Department of Agriculture and Food 16. Viable solutions for barley powdery mildew, Madeline A. Tucker, Australian Centre for Necrotrophic Fungal Pathogens, Murdoch University Marketing 17. The importance of varietal accreditation in a post-deregulation barley marketing environment, Neil Barker, Barley Australia 18. Can Australia wheat meet requirements for a new middle east market? Robert Loughman, Larisa Cato, Department of Agriculture and Food, and Ken Quail, BRI Australia VARIETY PERFORMANCE 19. Sowing rate and time for hybrid vs open-pollinated canola, Mohammad Amjad and Mark Seymour, Department of Agriculture and Food 20. HYOLA® National Hybrid vs OP Canola Hybrid F1 vs Retained Seed Generation Trial Results and recommendations for growers, Justin Kudnig, Mark Thompson, Anton Mannes, Michael Uttley, Chris Fletcher, Andrew Etherton, Nick Joyce and Kate Light, Pacific Seeds Australia 21. HYOLA® National Hybrid vs OP Canola Sowing Rate Trial Results and plant population recommendations for Australian growers, Justin Kudnig, Mark Thompson, Anton Mannes, Michael Uttley, Andrew Etherton, Chris Fletcher, Nick Joyce and Kate Light, Pacific Seeds Australia; Peter Hamblin, Agritech Research Young, NSW, Michael Lamond, Agrisearch, York, Western Australia 22. Desi chickpea agronomy for 2010, Alan Meldrum, Pulse Australia and Wayne Parker, Department of Agriculture and Food 23. New wheat varieties – exploit the benefits and avoid the pitfalls, Steve Penny, Sarah Ellis, Brenda Shackley, Christine Zaicou, Shahajahan Miyan, Darshan Sharma and Ben Curtis, Department of Agriculture and Food 24. The influence of genetics and environment on the level of seed alkaloid in narrow-leafed lupins, Greg Shea1, Bevan Buirchell1, David Harris2 and Bob French1, 1Department of Agriculture and Food, 2ChemCentr

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Bi-allelic Loss-of-Function CACNA1B Mutations in Progressive Epilepsy-Dyskinesia.

The occurrence of non-epileptic hyperkinetic movements in the context of developmental epileptic encephalopathies is an increasingly recognized phenomenon. Identification of causative mutations provides an important insight into common pathogenic mechanisms that cause both seizures and abnormal motor control. We report bi-allelic loss-of-function CACNA1B variants in six children from three unrelated families whose affected members present with a complex and progressive neurological syndrome. All affected individuals presented with epileptic encephalopathy, severe neurodevelopmental delay (often with regression), and a hyperkinetic movement disorder. Additional neurological features included postnatal microcephaly and hypotonia. Five children died in childhood or adolescence (mean age of death: 9 years), mainly as a result of secondary respiratory complications. CACNA1B encodes the pore-forming subunit of the pre-synaptic neuronal voltage-gated calcium channel Cav2.2/N-type, crucial for SNARE-mediated neurotransmission, particularly in the early postnatal period. Bi-allelic loss-of-function variants in CACNA1B are predicted to cause disruption of Ca2+ influx, leading to impaired synaptic neurotransmission. The resultant effect on neuronal function is likely to be important in the development of involuntary movements and epilepsy. Overall, our findings provide further evidence for the key role of Cav2.2 in normal human neurodevelopment.MAK is funded by an NIHR Research Professorship and receives funding from the Wellcome Trust, Great Ormond Street Children's Hospital Charity, and Rosetrees Trust. E.M. received funding from the Rosetrees Trust (CD-A53) and Great Ormond Street Hospital Children's Charity. K.G. received funding from Temple Street Foundation. A.M. is funded by Great Ormond Street Hospital, the National Institute for Health Research (NIHR), and Biomedical Research Centre. F.L.R. and D.G. are funded by Cambridge Biomedical Research Centre. K.C. and A.S.J. are funded by NIHR Bioresource for Rare Diseases. The DDD Study presents independent research commissioned by the Health Innovation Challenge Fund (grant number HICF-1009-003), a parallel funding partnership between the Wellcome Trust and the Department of Health, and the Wellcome Trust Sanger Institute (grant number WT098051). We acknowledge support from the UK Department of Health via the NIHR comprehensive Biomedical Research Centre award to Guy's and St. Thomas' National Health Service (NHS) Foundation Trust in partnership with King's College London. This research was also supported by the NIHR Great Ormond Street Hospital Biomedical Research Centre. J.H.C. is in receipt of an NIHR Senior Investigator Award. The research team acknowledges the support of the NIHR through the Comprehensive Clinical Research Network. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, Department of Health, or Wellcome Trust. E.R.M. acknowledges support from NIHR Cambridge Biomedical Research Centre, an NIHR Senior Investigator Award, and the University of Cambridge has received salary support in respect of E.R.M. from the NHS in the East of England through the Clinical Academic Reserve. I.E.S. is supported by the National Health and Medical Research Council of Australia (Program Grant and Practitioner Fellowship)

Herbicide-Resistant Crop Management: A Canadian Perspective

The Canadian perspective is focused on the comprehensive approaches to weed resistance in Canada for GE canola, corn, and soybeans, including reporting requirements, BMPs to minimize resistance, and systematic monitoring for herbicide-resistant weeds. Resistance management plans have been required to deregulate herbicide-resistant crops for more than a decade in Canada. Following deregulation, a framework that incorporates weed surveys was developed to facilitate the early identification of herbicide-resistant weeds through environmental monitoring of released GE crops