Asymptomatic bacteriuria in sickle cell disease: a cross-sectional study

BACKGROUND: It is known that there is significant morbidity associated with urinary tract infection and with renal dysfunction in sickle cell disease (SCD). However, it is not known if there are potential adverse outcomes associated with asymptomatic bacteriuria (ASB) infections in sickle cell disease if left untreated. This study was undertaken to determine the prevalence of ASB, in a cohort of patients with SCD. METHODS: This is a cross-sectional study of patients in the Jamaican Sickle Cell Cohort. Aseptically collected mid-stream urine (MSU) samples were obtained from 266 patients for urinalysis, culture and sensitivity analysis. Proteinuria was measured by urine dipsticks. Individuals with abnormal urine culture results had repeat urine culture. Serum creatinine was measured and steady state haematology and uric acid concentrations were obtained from clinical records. This was completed at a primary care health clinic dedicated to sickle cell diseases in Kingston, Jamaica. There were 133 males and 133 females in the sample studied. The mean age (mean ± sd) of participants was 26.6 ± 2.5 years. The main outcome measures were the culture of ≥ 10(5 )colony forming units of a urinary tract pathogen per milliliter of urine from a MSU specimen on a single occasion (probable ASB) or on consecutive occasions (confirmed ASB). RESULTS: Of the 266 urines collected, 234 were sterile and 29 had significant bacteriuria yielding a prevalence of probable ASB of 10.9% (29/266). Fourteen patients had confirmed ASB (prevalence 5.3%) of which 13 had pyuria. Controlling for genotype, females were 14.7 times more likely to have confirmed ASB compared to males (95%CI 1.8 to 121.0). The number of recorded visits for symptomatic UTI was increased by a factor of 2.5 (95% CI 1.4 to 4.5, p < 0.005) but serum creatinine, uric acid and haematology values were not different in patients with confirmed ASB compared with those with sterile urine. There was no association with history of gram negative sepsis. CONCLUSION: ASB is a significant problem in individuals with SCD and may be the source of pathogens in UTI. However, further research is needed to determine the clinical significance of ASB in SCD

Approaches to sequence the HTT CAG repeat expansion and quantify repeat length variation

Background: Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder caused by the expansion of the HTT CAG repeat. Affected individuals inherit ≥36 repeats and longer alleles cause earlier onset, greater disease severity and faster disease progression. The HTT CAG repeat is genetically unstable in the soma in a process that preferentially generates somatic expansions, the proportion of which is associated with disease onset, severity and progression. Somatic mosaicism of the HTT CAG repeat has traditionally been assessed by semi-quantitative PCR-electrophoresis approaches that have limitations (e.g., no information about sequence variants). Genotyping-by-sequencing could allow for some of these limitations to be overcome. Objective: To investigate the utility of PCR sequencing to genotype large (&gt;50 CAGs) HD alleles and to quantify the associated somatic mosaicism. Methods: We have applied MiSeq and PacBio sequencing to PCR products of the HTT CAG repeat in transgenic R6/2 mice carrying ∼55, ∼110, ∼255 and ∼470 CAGs. For each of these alleles, we compared the repeat length distributions generated for different tissues at two ages. Results: We were able to sequence the CAG repeat full length in all samples. However, the repeat length distributions for samples with ∼470 CAGs were biased towards shorter repeat lengths. Conclusion: PCR sequencing can be used to sequence all the HD alleles considered, but this approach cannot be used to estimate modal allele size or quantify somatic expansions for alleles ⪢250 CAGs. We review the limitations of PCR sequencing and alternative approaches that may allow the quantification of somatic contractions and very large somatic expansions

Crop Updates 2000 - Weeds

This session covers thirty six papers from different authors: INTRODUCTION, Vanessa Stewart Agriculture Western Australia INTEGRATED WEED MANAGEMENT Effect of seeding density, row spacing and Trifluralin on the competitive ability of Annual Ryegrass in a minimum tillage system, David Minkey, Abul Hashem, Glen Riethmuller and Martin Harries, Agriculture Western Australia High wheat seeding rates coupled with narrow row spacing increases yield and suppresses grass, Peter Newman1 and Cameron Weeks2,1Agronomist, Elders Limited 2Mingenew/Irwin Group Resistant ryegrass management in a wheat – lupin rotation, Abul Hashem, Harmohinder S. Dhammu, Aik Cheam, David Bowran and Terry Piper, Agriculture Western Australia Integrated weed management – Will it work with my rotation? Alexandra Wallace, Agriculture Western Australia Long term herbicide resistance trial – Mingenew, Peter Newman Elders, Cameron Weeks Mingenew-Irwin Group Is two years enough? Bill Roy, Agricultural Consulting and Research Services The fate of ryegrass seed when sheep graze chaff cart heaps, Keith L. Devenish1 and Lisa J. Leaver2 1 Agriculture Western Australia, 2Curtin University of Technology, Muresk Institute of Agriculture Can blanket wiping and crop topping prevent seed set of resistant wild radish and mustard? StAbul Hashem, Harmohinder Dhammu, Vanessa Stewart, Brad Rayner and Mike Collins, Agriculture Western Australia The value of green manuring in the integrated management of ryegrass, Marta Monjardino1,2, David Pannell2, Stephen Powles1 ,1Western Australia Herbicide Resistance Initiative, 2Agricultural and Resource Economics, University of Western Australia Some ways of increasing wheat competitiveness against ryegrass,, Mike Collins Centre for Cropping Systems, Agriculture Western Australia WEED BIOLOGY Understanding and driving weed seed banks to very low levels, Sally Peltzer, Agriculture Western Australi HERBICIDE RESISTANCE Cross resistance of chlorsulfuron-resistant wild radish to imidazolinones, Abul Hashem, Harmohinder Dhammu and David Bowran, Agriculture Western Australia Investigation of suspected triazine resistant ryegrass populations for cross-resistance and multiple resistance to herbicides, Michael Walsh, Charles Boyle and Stephen Powles, Western Australian Herbicide Resistance Initiative, University of Western Australia Genetics and fitness of glyphosate resistant ryegrass, S. Powles1, P. Neve1, D. Lorraine-Colwill2, C. Preston2 ,1WAHRI, University of Western Australia 2 CRC Weed Management Systems, University of Adelaide Managing herbicide resistance – the effect of local extinction of resistance genes, Art Diggle1, Paul B. Neve2, Stephen B. Powles2 ,1Agriculture Western Australia, 2WAHRI, Faculty of Agriculture, University of Western Australia The double knock - the best strategy for conserving glyphosate susceptibility? Paul B. Neve1, Art Diggle2, Stephen B. Powles1,1WAHRI, Faculty of Agriculture, University of Western Australia, 2Agriculture Western Australia Wild radish had evolved resistance to triazines, Abul Hashem, Harmohinder S. Dhammu, David Bowran and Aik Cheam, Agriculture Western Australia Ryegrass resistance in Western Australia – where and how much? Rick Llewellyn and Stephen Powles, Western Australian Herbicide Resistance Initiative, Faculty of Agriculture, University of Western Australia Wild radish herbicide resistance survey, Michael Walsh, Ryan Duane and Stephen Powles, Western Australian Herbicide Resistance Initiative, University of Western Australia Knockdown resistance in the Western Australian wheatbelt – a proposed survey, Paul B. Neve1, Abul Hashem2, Stephen B. Powles1,1Western Australian Herbicide Resistance Initiative, University of Western Australia, 2Agriculture Western Australia Diflufenican resistant wild radish, Aik Cheam, Siew Lee, David Bowran, David Nicholson and Abul Hashem, Agriculture Western Australi Multiple resistance to triazines and diflufenican further complicates wild radish control, Aik Cheam, Siew Lee, David Bowran, David Nicholson and Abul Hashem, Agriculture Western Australia HERBICIDE TOLERANCE 25. Herbicide tolerance of lupins, Terry Piper, Weed Science Group, Agriculture Western Australia 26. Tanjil lupins will tolerate metribuzin under the right conditions, Peter Newman, Agronomist Elders Limited and Cameron Weeks, Mingenew/Irwin Group 27. Herbicide damage does not mean lower yield in Lupins, Peter Carlton, Trials Coordinator, Elders Limited 28. Herbicide tolerance of new pea varieties, Dr Terry Piper, Agriculture Western Australia 29. Herbicide tolerance of (waterlogged) wheat, Dr Terry Piper, Agriculture Western Australia 30. Wheat tolerance trials – Mingenew 1999, Peter Newman1, Cameron Weeks2 and Stewart Smith3,1Elders, Mingenew, 2Mingenew-Irwin Group,3Agriculture Western Australia ISSUES OF TRIFLURALIN USE 31. Trifluralin works better on ryegrass when no-tilling into thick wheat stubbles as granules, or mixed with limesand, Bill Crabtree, WANTFA Scientific Officer 32. Increasing trifluralin rate did not compensate for delaying incorporation, Bill Crabtree, WANTFA Scientific Officer 33. Poor emergence survey, 1999, Terry Piper, Weed Science Group, Agriculture Western Australia HERBICIDES – ISSUES AND OPTIONS 34. AFFINITY 400DF – A new herbicide with a new mode of action (Group G) for Broadleaf Weed Control in Cereals, Gordon Cumming, Technical Officer, Crop Care Australasia 35 Herbicide screening for Marshmallow, David Minkey1 and David Cameron2,1Agriculture Western Australia, 2Elders Ltd, Merredin 36. The control of Capeweed in Clearfield Production System for Canola, Mike Jackson and Scott Paton, Cyanamid Agriculture Pty Ltd 37.Effect of herbicides Tordonä 75D and Lontrelä,used for eradication of Skeleton Weed, on production of Lupins I the following seasons, John R. Peirce and Brad J. Rayner, Agriculture Western Australia INDUSTRY PROTECTION 38. Graingaurd – Opportunities for agribusiness to help protect the West Australian grains industry, Greg Shea, Executive Officer, GrainGuard Agriculture Western Australi

Crop Updates 2001 - Weeds

This session covers forty six papers from different authors: 1. INTRODUCTION, Vanessa Stewart, Agriculture Western Australia PLENARY 2. Wild radish – the implications for our rotations, David Bowran, Centre for Cropping Systems INTEGRATED WEED MANAGEMENT IWM system studies/demonstration sites 3. Integrated weed management: Cadoux, Alexandra Wallace, Agriculture Western Australia 4. A system approach to managing resistant ryegrass, Bill Roy, Agricultural Consulting and Research Services Pty Ltd, York 5. Long term herbicide resistance demonstration, Peter Newman, Agriculture Western Australia, Cameron Weeks, Tony Blake and Dave Nicholson 6. Integrated weed management: Katanning, Alexandra Wallace, Agriculture Western Australia 7. Integrated weed management: Merredin, Vanessa Stewart, Agriculture Western Australia 8. Short term pasture phases for weed control, Clinton Revell and Candy Hudson, Agriculture Western Australia Weed biology – implications for IWM 9. Competitivness of wild radish in a wheat-lupin rotation , Abul Hashem, Nerys Wilkins, and Terry Piper, Agriculture Western Australia 10. Population explosion and persistence of wild radish in a wheat-lupin rotation, Abul Hashem, Nerys Wilkins, Aik Cheam and Terry Piper , Agriculture Western Australia 11. Variation is seed dormancy and management of annual ryegrass, Amanda Ellery and Ross Chapman, CSIRO 12. Can we eradicate barley grass, Sally Peltzer, Agriculture Western Australia Adoption and modelling 13. Where to with RIM? Vanessa Stewart1 and Robert Barrett-Lennard2, 1Agriculture Western Australia, 2Western Australian Herbicide Resistance Initiative (WAHRI) 14. Multi-species RIM model, Marta Monjardino1,2, David Pannell2 and Stephen Powles1 1Western Australian Herbicide Resistance Initiative (WAHRI), 2ARE, University of Western Australia 15. What causes WA grain growers to adopt IWM practices? Rick Llewellyn, WAHRI/ARE, Faculty of Agriculture, University of WA New options for IWM? 16. Fuzzy tramlines for more yield and less weeds, Paul Blackwell Agriculture Western Australia, and Maurice Black, Harbour Lights Estate, Geraldton 17. Inter-row knockdowns for profitable lupins, Paul Blackwell, Agriculture Western Australia and Miles Obst, Farmer Mingenew 18. Row cropping and weed control in lupins, Mike Collins and Julie Roche, Agriculture Western Australia 19. Cross seedimg suppresses annual ryegrass and increases wheat yield, Abul Hashem, Dave Nicholson and Nerys Wilkins Agriculture Western Australia 20. Weed control by chaff burial, Mike Collins, Agriculture Western Australia HERBICIDE RESISTANCE 21. Resistance in wild oats to Fop and Dim herbicides in Western Australia, Abul Hashem and Harmohinder Dhammu, Agriculture Western Australia 22. Triazine and diflufenican resistance in wild radish: what it means to the lupin industry, Aik Cheam, Siew Lee, David Nicholson and Peter Newman, Agriculture Western Australia 23. Comparison if in situ v seed testing for determining herbicide resistance, Bill Roy, Agricultural Consulting and Research Services Pty Ltd, York HERBICIDE TOLERANCE 24. Phenoxy herbicide tolerance of wheat, Peter Newman and Dave Nicholson, Agriculture Western Australia 25. Tolerance of wheat to phenoxy herbicides, Harmohinder S. Dhammu, Terry Piper and Mario F. D\u27Antuono, Agriculture Western Australia 26. Herbicide tolerance of new wheats, Harmohinder S. Dhammu, Terry Piper and David F. Nicholson, Agriculture Western Australia 27. Herbicide tolerance of durum wheats, Harmohinder S. Dhammu, Terry Piper and David F. Nicholson, Agriculture Western Australia 28. Herbicide tolerance of new field pea varieties, Harmohinder S. Dhammu, Terry Piper, David F. Nicholson, and Mario F. D\u27Antuono, Agriculture Western Australia 29. Herbicide tolerance of Cooke field peas on marginal soil, Harmohinder S. Dhammu, Terry Piper, David F. Nicholson, and Mario F. D\u27Antuono, Agriculture Western Australia 30. Herbicide tolerance of some annual pasture legumes adapted to coarse textured sandy soils, Clinton Revell and Ian Rose, Agriculture Western Australia 31 Herbicide tolerance of some annual pasture legumes adapted to fine textured clay soils, Clinton Revell and Ian Rose, Agriculture Western Australia WEED CONTROL IN LUCERNE 32. Management of weeds for Lucerne establishment, Diana Fedorenko, Clayton Butterly, Stuart McAlpine, Terry Piper and David Bowran, Centre for Cropping Systems, Agriculture Western Australia 33. Management of weeds in the second year of Lucerne, Diana Fedorenko, Clayton Butterly, Stuart McAlpine, Terry Piper and David Bowran, Centre for Cropping Systems, Agriculture Western Australia 34. Residual effects of weed management in the third year of Lucerne, Diana Fedorenko, Clayton Butterly, Stuart McAlpine, Terry Piper and David Bowran, Centre for Cropping Systems, Agriculture Western Australia 35. Herbicide tolerance and weed control in Lucerne, Peter Newman, Dave Nicholson and Keith Devenish Agriculture Western Australia HERBICIDES – NEW PRODUCTS/PRODUCE USES; USE New products or product use 36. New herbicide options for canola, John Moore and Paul Matson, Agriculture Western Australia 37. Chemical broadleaf weed management in Peaola, Shannon Barraclough and Lionel Martin, Muresk Institute of Agriculture, Curtin University of Technology 38. Balance® - a new broad leaf herbicide for the chickpea industry, Mike Clarke, Jonas Hodgson and Lawrence Price, Aventis CropScience 39. Marshmallow – robust herbicide strategies, Craig Brown, IAMA Agribusiness 40. Affinity DF – a prospective option for selective in-crop marshmallow control, Gordon Cumming, Technical Officer, Crop Care Australasia 41. A new formulation of Carfentrazone-ethyl for pre-seeding knockdown control of broadleaved weeds including Marshmallow, Gordon Cumming, Technical Officer, Crop Care Australasia Herbicide use 42. Autumn applied trifluralin can be effective! Bill Crabtree, Scientific Officer, Western Australian No-Tillage Farmers Association 43. Which knockdown herbicide for small ryegrass? Peter Newman and Dave Nicholson, Agriculture Western Australia 44. Poor radish control with Group D herbicides in lupins, Peter Newman and Dave Nicholson, Agriculture Western Australia WEED ISSUES 45. Distribution and incidence of aphids and barley yellow dwarf virus in over-summering grasses in the WA wheatbelt, Jenny Hawkes and Roger Jones, CLIMA and Agriculture Western Australia 46. e-weed, Vanessa Stewart, Agriculture Western Australia CONTRIBUTING AUTHOR CONTACT DETAIL

Crop Updates 2002 - Weeds

This session covers fifty eight papers from different authors: 1. INTRODUCTION Vanessa Stewart, DEPARTMENT OF AGRICULTURE INTEGRATED WEED MANAGEMENT IWM system studies / demonstration sites 2. Major outcomes from IWM demonstration sites, Alexandra Douglas Department of Agriculture 3. Integrated weed management: Katanning, Alexandra Douglas Department of Agriculture 4. Integrated weed management: Merredin, Vanessa Stewart Department of Agriculture 5. Long term resistance site: Get ryegrass numbers low and keep them low! Peter Newman and Glen Adams Department of Agriculture 6. Using pastures to manage ryegrass populations, Andrew Blake and Natalie Lauritsen Department of Agriculture Weed biology and competition 7. Understanding the weed seed bank life if important agricultural weeds, Sally Peltzer and Paul Matson Department of Agriculture 8. Consequence of radish competition on lupin nutrients in wheat-lupin rotation, Abul Hashem and Nerys Wilkins Department of Agriculture 9. Consequence of ryegrass competition on lupin nutrients in a wheat-lupin rotation, Abul Hashem and Nerys Wilkins Department of Agriculture 10. Brome grass too competitive for early sown wheat in a dry year at Mullewa, Peter Newman and Glenn Adam Department of Agriculture Crop establishment and weed management 11. Seeding rate, row spacing and herbicides for weed control, David Minkey Department of Agriculture 12. Effect of different seeding methods on wheat and ryegrass, Abul Hashem, Glen Riethmuller and Nerys Wilkins Department of Agriculture 13. Role of tillage implements and trifluralin on the effectiveness of the autumn tickle for stimulating annual ryegrass emergence, Tim Cusack1, Kathryn Steadman1 and Abul Hashem2,1Western Australia Herbicide Resistance Initiative, UWA; 2Department of Agriculture, 14. Timing of autumn tickle in important for non-wetting soils, Pippa Michael1, Peter Newman2 and Kathryn Steadman 2, 1Western Australia Herbicide Resistance Initiative, UWA, 2Department of Agriculture 15. Early investigation into weed seed burial by mouldboard plough, Sally Peltzer and Alex Douglas Department of Agriculture 16. Rolling post-emergent lupins to improve weed emergence and control on loamy sand, Paul Blackwell, Department of Agriculture and Dave Brindal, Strawberry via Mingenew IWM tools 17. Crop topping in 2001: How did we do? Peter Newman and Glenn Adam Department of Agriculture 18. Wickwipers work! Peter Newman and Glenn Adam Department of Agriculture 19. Wild radish and ryegrass seed collection at harvest: Chaff carts and other devices, Michael Walsh Western Australia Herbicide Resistance Initiative, UWA and Wayne Parker Department of Agriculture 20. Improving weed control in grazed pastures using legumes with low palatability, Clinton Revell, Giles Glasson Department of Agriculture, and Dean Thomas Faculty of Agriculture, University of Western Australia Adoption and modelling 21. Grower weed survey, Peter Newman and Glenn Adam Department of Agriculture 22. Agronomist survey, Peter Newman and Glenn Adam Department of Agriculture 23. Ryegrass RIM model stands the test of IWM field trial data, Alister Draper Western Australia Herbicide Resistance Initiative, UWA and Bill Roy, Western Australia Herbicide Resistance Initiative, UWA Agricultural Consulting and Research Services 24. Multi-species RIM: An update, Marta Monjardin1,2, David Pannell2 and Stephen Powles 1, 1Western Australia Herbicide Resistance Initiative, UWA, 2 ARE, University of Western Australia 25. RIM survey feedback, Robert Barrett-Lennard and Alister Draper Western Australia Herbicide Resistance Initiative, UWA 26. Effect of historic input and product prices on choice of ryegrass management strategies, Alister Draper1 and Martin Bent2, 1Western Australia Herbicide Resistance Initiative, UWA, 2Muresk Institute of Agriculture 27. Living with ryegrass – trading off weed control and economic performance, Martin Bent1 and Alister Draper2 , 1Muresk Institute of Agriculture, Curtin University, 2Western Australia Herbicide Resistance Initiative, UWA HERBICIDE RESISTANCE 28. Glyphosate resistance in WA and Australia: Where are we at? Paul Neve1, Art Diggle2, Patrick Smith3, Mechelle Owen1, Abul Hashem2, Christopher Preston4and Stephen Powles1,1Western Australian Herbicide Resistance Initiative, University of Western Australia, 2Department of Agriculture, 3CSIRO Sustainable Ecosystems, 4CRC for Australian Weed Management and Department of Applied and Molecular Ecology, Waite Campus, University of Adelaide 29. We need you weeds: A survey of knockdown resistance in the WA wheatbelt, Paul Neve1, Mechelle Owen1, Abul Hashem2 and Stephen Powles1 1Western Australian Herbicide Resistance Initiative, University of Western Australia, 2Department of Agriculture 30. A test for resistance testing, Mechelle Owen, Tracey Gillam, Rick Llewellyn and Steve Powles,Western Australia Herbicide Resistance Initiative, University of Western Australia 31. In field testing for herbicide resistance, a purpose built multi-treatment spray boom with results from 2001, Richard Quinlan, Elders Ltd 32. Advantages and limitations of a purpose built multi-treatment spray boom, Richard Quinlan, Elders Ltd 33. Group F resistant wild radish: What’s new? Aik Cheam, Siew Lee Department of Agriculture, and Mike Clarke Aventis Crop Science 34. Cross resistance of Brodal® resistant wild radish to Sniper®, Aik Cheam and Siew Lee, Department of Agriculture 35. Managing a biotype of wild radish with Group F and Group C resistance, Aik Cheam, Siew Lee, David Nicholson, Peter Newman Department of Agriculture and Mike Clarke, Aventis Crop Science HERBICIDE TOLERANCE 36. Herbicide tolerance of new wheat varieties, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Agriculture Western Australia 37. Response of barley varieties to herbicides, Harmohinder S. Dhammu, Terry Piper, Department of Agriculture 38. Tolerance of barley to phenoxy herbicides, Harmohinder S. Dhammu, Terry Piper, Department of Agriculture and Chad Sayer, Nufarm Australia Limited 39. Response of Durum wheats to herbicides, Harmohinder S. Dhammu, Terry Piper, Department of Agriculture 40. Response of new field pea varieties to herbicides, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Department of Agriculture 41. Herbicide tolerance of Desi chickpeas on marginal soil, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Department of Agriculture 42. Herbicide tolerance of newer lupin varieties, Terry Piper, Harmohinder Dhammu and David Nicholson, Department of Agriculture 43. Herbicide tolerance of some annual pasture legumes, Clinton Revell and Ian Rose, Department of Agriculture 44. Herbicide tolerance of pasture legumes, Andrew Blake, Department of Agriculture HERBICIDES – NEW PRODUCTS/PRODUCT USES; USE 45. Knockdown herbicides do not reliably kill small grass weeds, Peter Newman and Glenn Adam, Department of Agriculture 46. ‘Hair Cutting’ wheat with Spray.Seed®: Does it work? Peter Newman and Glenn Adam, Department of Agriculture 47. ‘Haircutting’: Does the number one cut work? Robert Barrett-Lennard1 and Jerome Critch2,1WA Herbicide Resistance Initiative, University of WA, 2Student, University of WA 48. Hammer EC (Carfentrazone-ethyl): A mixing partner for glyphosate to enhance the control of difficult broadleaf weeds, Gordon R. Cumming, Crop Care Australasia 49. Marshmallow control in reduced tillage systems, Sam Taylor, Wesfarmers Landmark 50. Herbicide options for summer germinating marshmallow, Vanessa Stewart, Department of Agriculture 51. Dual Gold® safe in a dry year at Coorow, Peter Newman and Glenn Adam, Department of Agriculture 52. The effect of glyphosate, paraquat and diquat as a crop topping application on the germination of barley, John Moore and Roslyn Jettner, Department of Agriculture 53. Herbicide options for melon control, Vanessa Stewart, Department of Agriculture 54. Herbicide options for the control of Chloris truncate (windmill grass) Vanessa Stewart, Department of Agriculture 55. Allelopathic effects of crop, pasture and weed residues on subsequent crop and pasture establishment, Stuart Bee1, Lionel Martin1, Keith Devenish2 and Terry Piper2, 1Muresk Institute of Agriculture, Curtin University of Technology, Northam, Western Australia, 2Centre for Cropping Systems, Department of Agriculture WEED ISSUES 56. Role of Roundup ReadyÒ canola in the farming system, Art Diggle1, Patrick Smith2, Paul Neve3, Felicity Flugge4, Amir Abadi5 and Stephen Powles3, 1Department of Agriculture; 2CSIRO, Sustainable Ecosystems; 3Western Australian Herbicide Resistance Initiative; 4Centre for Legumes in Mediterranean Agriculture; 5Touchstone Consulting 57. ’Weeds for Feed’ and livestock enterprise structures: A feasibility study and farmer survey in the north-easern wheatbelt, Duncan Peter and Stuart McAlpine, Department of Agriculture and Liebe Group, Buntine 58. e-weed, Vanessa Stewart, Agriculture Western Australi

The Southern African program on ecosystem change and society : an emergent community of practice

Sustainability-focused research networks and communities of practice have emerged as a key response and strategy to build capacity and knowledge to support transformation towards more sustainable, just and equitable futures. This paper synthesises insights from the development of a community of practice on social-ecological systems (SES) research in southern Africa over the past decade, linked to the international Programme on Ecosystem Change and Society (PECS). This community consists of a network of researchers who carry out placebased SES research in the southern African region. They interact through various cross-cutting working groups and also host a variety of public colloquia and student and practitioner training events. Known as the Southern African Program on Ecosystem Change and Society (SAPECS), its core objectives are to: (1) derive new approaches and empirical insights on SES dynamics in the southern African context; (2) have a tangible impact by mainstreaming knowledge into policy and practice; and (3) grow the community of practice engaged in SES research and governance, including researchers, students and practitioners. This paper reflects on experiences in building the SAPECS community, with the aim of supporting the development of similar networks elsewhere in the world, particularly in the Global South.https://www.tandfonline.com/journals/TBSMam2024Future AfricaSDG-11:Sustainable cities and communitie

Evenness mediates the global relationship between forest productivity and richness

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions