ISSN: 0815-2195 |
Published by RMIT Publishing
No Issue Number
- Volume 26 Issue 3 - Weed Psychology and the War on Weeds
What part do emotions play in our dealings with weeds, including our decisions about waging war on weeds, and which plants to regard as the enemy? How did fear and loathing become so widespread as the typical response to weeds?
- Volume 26 Issue 3 - Changing of the Guard: Moving from a War on Weeds to an Outcome-orientated Weed Management System
Downey, Paul O
Weed management has been likened to a war - the war on weeds. Whilst the concept of a war has created a sense of unity, supported by 'propaganda' and emotive language, the campaign has been far from a success. In fact it has actually hampered weed management by maintaining a deep-seated emphasis on the act of killing weeds, rather than on the outcome of that killing - an example of an outcome might be the response of native species that are threatened by a particular weed. In order to increase the effectiveness of weed management I argue that it is time for a changing of the guard or a transition from this so-called 'war on weeds' to a new approach: one that is focused on the outcome, which is not a war. Whilst an outcome-orientated weed management system is not new, i.e. it has already been used in a few specific cases, it is distinctly different from the concept of a war, and more in line with the broader objectives of many weed management programs. In order to transition to an outcome-orientated weed management system several challenges need to be overcome, specifically around establishing appropriate goals and monitoring weed management programs. In addition we need to ensure policy is aligned with management and research. Lastly, some deeply entrenched individual and institutional views on weed management need to be overcome. None of the challenges outlined pose a significant barrier to a transition to an outcome-orientated approach. Given the failure of the war on weeds it is now time to make such a transition.
- Volume 26 Issue 3 - Coastal Plants: A Guide to the Identification and Restoration of Plants of the Perth Region [Book Review]
- Volume 26 Issue 3 - Diseases of Vegetable Crops in Australia [Book Review]
- Volume 26 Issue 3 - Herbicide Resistance in Wild Oats ('Avena' Spp.) in Southern New South Wales
Broster, JC; Koetz, EA; Wu, H
A random survey across the southern cereal cropping zone of New South Wales was conducted in 2007 to determine the extent of herbicide resistance in wild oat populations. In total, 113 samples were collected from the 181 properties visited. These samples were screened against the herbicide Groups (A, B, J, M and Z) commonly used for wild oat control in Australia. Resistance was present to Group A 'fop' (38%) and Group Z (10%) herbicides, increasing from 5% and 0% respectively in previous surveys (1991 and 1994). No samples were found to be resistant to clethodim, mesosulfuron, triallate or glyphosate. The significant increase in the incidence of resistance to Group A 'fop' and Z herbicides, combined with a high level of resistance in annual ryegrass from these sites, highlights the importance of adopting an integrated approach to weed management. Such an approach is also necessary for maintaining a nil or low level of resistance in Groups B, J and M, and extending the commercial life of these effective chemicals.
- Volume 26 Issue 3 - Weeds or Wild Nature: A Permaculture Perspective
Land design and management informed by permaculture principles tends to regard naturalized species of plants as assets that should be managed to stabilize water and soil, build biomass, fix nutrients, ameliorate microclimate and provide habitat, fodder, fuel and food in the early stages of system development. While naturalized species may be given a lower value in permaculture design than species regarded as indigenous to the site and region, the typical designation of naturalized species as 'invasive species' or 'environmental weeds' is typically rejected as anti-ecological thinking. The background and basis for this positive view of naturalized plants is not well understood, and has led to strong and persistent criticism of permaculture by those promoting the orthodox view of naturalized species as invasives. This has itself influenced the practices and teaching of many permaculturists to moderate or compromise the permaculture approach to naturalized species. Consequently the 'weeds or wild nature' controversy is alive and well within the permaculture movement. As one of the co-originators of the permaculture concept I am in a position to provide a unique perspective on the evolution of this debate and its connection to wider debate on this issue in conservation and land management networks. Inevitably this story is partly an historical and personal one rather than a review of scientific literature on the subject.
- Volume 26 Issue 3 - Agricultural Bioenergy Cropping in Victoria - Balancing the Issues
Shelley, Bruce; Rogers, Mary-Jane; Allinson, Graeme; Day, Nathan
There has been considerable interest in biofuels and bioenergy production (the generation of energy from biomass), as alternative agricultural industries for the future. High oil prices, diminishing total oil supply, the energy security debate, growing environmental awareness and the need to develop sustainable regional agricultural industries under climate change, are issues that are driving this interest. The Victorian Government, through its Agriculture and Fisheries Four Year Strategy, recognizes the benefits of developing a sustainable bioenergy industry, particularly using second generation biofuels. The development of a sustainable biofuel industry in Victoria may have a major impact on the Victorian economy by potentially: lessening the dependence on fossil fuels; enabling new markets and alternative income streams for farmers to be developed; developing new industries for regional Victoria; assisting in the reduction of greenhouse gas emissions; developing land management systems which provide efficient, low emissions energy sources, while reducing greenhouse gas (GHG) emissions. However, while bioenergy offers potential for significant benefits, it is critical that the economic, environmental (including weed risk, lifecycle GHG emissions and energy balance) and social values of any potential biofuel crop be fully assessed before its introduction and promotion.
- Volume 26 Issue 3 - Contentious Perspectives on Weeds: Nettle, Dock, Dandelion and Wild Fennel - Environmental Weeds or Environmental Belonging'
In an essay on the practice of exotic mushroom foraging by the Polish community, Max Kwiatkowski argues for a deeper understanding of what he terms 'ethnoscape', the ethnic-specific interaction with landscape, its values and cultural returns. The act of foraging has been exercised by indigenous and nonindigenous people alike, the latter usually focusing on non-indigenous flora. With this paper I will present the need to acknowledge the social imperative of environmental belonging, a necessary aspect to consider when fostering care and kinship in these times of disconnection and alienation. I argue that the process of simplistic labelling of spontaneous exotic species - as good or bad - needs to address the reality of the Australian social and ecological make-up. Tim Low in his book Feral Future presents the Australian landscape, as defined in the media and politics, as a cultural construct, a subjective interpretation, and used in a too-generic sense to outline a unified national identity. As I speak, people from various cultures gather for road trips to the edges of cities to pursue a practice of environmental belonging: foraging for weeds.
- Volume 26 Issue 3 - 'Carpe Diem' - Seizing the Day. Successful Engagement in a Changing Society
Johnson, Stephen B
Society is constantly changing. The people we seek to engage are no different. Successful engagement in a changing society requires continual assessment of our communication techniques. This will mean examining time worn methods to ensure we continue to be successful. One way to continue to successfully engage others is to understand their basic values and key drivers. Many of these are influenced by society. Examining current societal values can help us do this, as can critical analysis about how society may change in the future. This paper describes five key societal changes since at least the 1980s: the increased busyness of people and the world; the workplace gender revolution; the decrease in public investment in education; the demographic shift in the workforce/community; and the information technology revolution. It describes how these changes are impacting in our society and poses ideas about how we can continue to successfully engage people in a changing society.
- Volume 26 Issue 1 - The Biology of Australian Weeds 57. 'Sclerolaena birchii' (F.Muell.) Domin
Auld, Bruce A; Johnson, Stephen B
Explained in its simplest sense, if farmers fail to control weeds on their farms, then the risk of infestation increases to surrounding farms. In the case of native species, it is difficult to argue that there is a liability for allowing its spread onto land where it naturally occurs, whether presently or historically.
- Volume 26 Issue 2 - Weed Control and Wheat Cultivars ('Triticum aestivum' L.) Responses to Metribuzin Application Rate and Timing in Iran
Zand, Eskandar; Baghestani, Mohammad Ali; Mesgaran, Mohsen B; Pourazr, Reza; Sarani, Mansour; Younes-Abadi, Masoumeh; Mansourian, Sahar
Field experiments were established at four locations in Iran to evaluate the efficacy of metribuzin in controlling weeds in winter wheat. Metribuzin was applied either post-emergence (POST) or pre-emergence (PRE) at 0, 0.35, 0.52 and 0.70 g a.i. ha-1. At each location three conventionally planted wheat cultivars were tested. In most cases weed control increased with metribuzin rate following a linear or curvilinear trend with an application rate of 0.5 kg ha−1 a.i. providing an acceptable level of control. PRE applied metribuzin resulted in better control of weeds at Ahvaz while POST treatments were more effective at Karaj with no differences between PRE and POST treatments at two other locations (Zabol and Gorgan). Wheat yields increased with metribuzin rate at two locations (Ahvaz and Zabol) or showed minor (Karaj) to no changes (Gorgan) across application rates. Wheat yields were higher in PRE treated plots than in POST at Ahvaz, but lower at Karaj and did not vary at Zabol (with one exception) or Gorgan. Wheat cultivars also varied in their responses to metribuzin application rate or timing. Finally, metribuzin could be applied at 0.5 kg ha-1 a.i. (regardless of application timing) but not at higher rates at Ahvaz and Karaj, although higher rates at Zabol and Gorgan could provide both an acceptable level of weed control and wheat yield gain as well.
- Volume 26 Issue 1 - Diversity and Integrated Management of Weeds in Highland Wheat of Northern Ethiopia
Asres, Bekele; Das, TK
In a survey of wheat fields in northern Ethiopia, of 24 weed species observed nine were monocotyledons and 15 dicotyledons. Dicotyledonous weeds made up 62.5% of the individual weed species and 83.1% of the total weed population, while monocotyledonous weeds were 37.5% and 16.9% respectively. Chrysanthemum segetum L. (corn marigold), Polygonum nepalense Meisn. (smartweed), Galium spurium L. (false cleavers), Spergula arvensis L. (corn spurrey) and Phalaris paradoxa L. (bristle-spiked canary grass), were the more important weeds with a frequency >30% and a dominance >5%. Polygonum nepalense and Spergula arvensis were dominant in the experimental wheat field. In an experimental field use of clean wheat seed gave a significant reduction in the total weed population (P less or equal 0.05) and an increase in wheat height, tiller and ear-bearing tiller numbers and seed yield over plots sown to contaminated seed. Clean seed + 2,4-D, or a tank-mix of 2,4-D and fenoxaprop-p-ethyl, applied at 25 days after emergence (DAE) plus hand weeding (HW) at 45 DAE resulted in a significant reduction in weed population at 70 DAE (P less or equal 0.05). These treatments, and treatments in which two hand weedings were employed at 25 and 45 DAE, gave higher wheat yield and net benefit and were comparable with the weed free check. Clean seed + 0.72 kg ha-1 2,4-D + HW at 45 DAE, however, resulted in the highest benefit: cost ratio.
- Volume 26 Issue 1 - A Case Study of Feral Olive ('Olea europaea') Dispersal in Northern Victoria. Part I: Plant Age and Growth Habit Characteristics
Hamilton, SD; Minotti, T; O'Dwyer, C; Brodie, G
European olive (Olea europaea L.) has successfully invaded several regions in Australia including the district surrounding Dookie College in northern Victoria. Feral populations of olives have spread from abandoned groves established in the late 1870s but due to a revitalization of the olive industry in the 1990s there is concern about increase in feral olives from this new source. Feral olives do not produce fruit until they are 10 years old so using techniques that can accurately age feral olive trees such as stem diameters or plant height will enable land managers to prioritize the control of reproductive individuals. This study evaluated ring counting of the stems on European olive trees and it proved to be a successful means of estimating the age of stems, with the estimated age of the widest stem the best estimator of plant age. Significant relationships between estimated stem ages, stem diameter, plant height and width were also established. The relationship between the diameter of the widest stem and estimated age will prove invaluable in developing a broad age structure profile of the feral European olive plants of the district.
- Volume 26 Issue 1 - Herbicide Resistance Levels in Annual Ryegrass ('Lolium rigidum' Gaud.) in Southern New South Wales
Broster, JC; Koetz, EA; Wu, H
In 2007 a random survey was conducted across the cereal cropping zone of southern New South Wales to determine the level of herbicide resistance in annual ryegrass populations. In total, 181 paddocks were visited resulting in 137 samples of annual ryegrass seed collected for testing. These samples were then screened to the commonly used herbicide groups (A, B, C, D and M) for annual ryegrass control in Australia. The majority of samples were resistant to Group A 'fop' (81%) and Group B 'SU' (70%) and 'Imi' (65%) herbicides. These represented increases from the 10-14% experienced in the previous survey in 1991. Seventy six percent of the 117 samples tested to five herbicide Groups (A 'fop, A 'dim, B, C or D) were resistant to two or more of the herbicide groups tested and only 9% were susceptible to all herbicides. Of particular interest is the minimal increase in resistance to simazine and trifluralin in the 16 years since the last survey, and only low incidence of glyphosate resistance was identified in this survey. The rapid increase in the incidence of herbicide resistance in annual ryegrass, particularly in Group A and Group B herbicides, highlights the importance of adopting an integrated approach in weed management. This integrated approach is also necessary for maintaining the low level of resistance in Groups C, D and M, and extending the commercial life of these effective chemicals.
- Volume 26 Issue 1 - Comparing the Outputs of Five Weed Risk Assessment Models Implemented in Australia: Are There Consistencies across Models'
Stone, Lynley M; Byrne, Margaret
Weed Risk Assessment models are increasingly used as decision support tools to prioritize weed species for management. Several models are implemented in Australia, but have not previously been compared for consistency of outputs. This study aims to determine if the outputs of four post-border models are comparable with each other and with the predictive outputs of a Border model. Each post-border model determines weed risk by combining three assessment criteria: Invasiveness, Impacts and Distribution. A common set of 24 species were assessed for weed risk to natural ecosystems through four post-border weed risk assessment models and the Australian Border model. Test species were ranked from highest to lowest weed risk to enable a comparison of model outputs. Pearson's correlation co-efficient and the co-efficient of variation were calculated for all outputs. Significant positive correlations were observed between the overall outputs of the post-border models. When compared individually, the outputs from the Invasiveness and Impacts criteria also showed significant positive correlations. The distribution criterion was a source of great variability in outputs, producing negative correlations. Outputs from the post-border models also showed significant positive correlations with those from the Border model. The area in greatest need of further development is determining the potential distribution of a species.
- Volume 26 Issue 1 - Temperate Woodland Conservation and Management [Book Review]
- Volume 26 Issue 1 - Australian Palms, Biogeography, Ecology and Systematics [Book Review]
- Volume 26 Issue 1 - Determining Best Control Methods for the National Environmental Alert List Species, 'Retama raetam (Forssk.) Webb (White Weeping Broom) in Western Australia
Bettink, KA; Brown, KL
Field experiments were conducted in Perth, Western Australia between 2006 and 2007 to assess the efficacy of various methods in controlling the National Environmental Alert List species Retama raetam (Forssk.) Webb (white weeping broom). Native to the Mediterranean region, this species is naturalized in Western Australia in relatively low numbers and mainly restricted to disturbed sites on the western edge of the Swan Coastal Plain. Hand removal and herbicide treatment are known effective methods of controlling seedlings, however a preferred method of treating mature plants has not yet been developed. This study tested a range of physical and chemical treatments, with results indicating that two treatments were highly effective on mature plants. Both the cut and paint method with 50% glyphosate and basal bark with triclopyr at 1.25 L 60 L-1 resulted in 100% mortality 12 months after application. Basal bark with tricoplyr and picloram (1.25 L 60 L-1) was less effective than triclopyr on its own, achieving only 70% mortality. Less effective again was the felling method, resulting in mortality in 50% of plants, the remaining 50% vigorously resprouting within five months. Foliar spraying with triclopyr (17 mL 10 L-1) and stem-injection with 50% glyphosate were less effective again, resulting in 40% and 50% mortality respectively 12 months after treatment.
- Volume 25 Issue 4 - Coolatai Grass ('Hyparrhenia hirta') Control at Cobbler Creek Recreation Park
The key aspects and features of the methods followed for the control of Coolatai grass (Hyparrhenia hirta) at Cobbler Creek Recreation (CRC) Park are discussed. The main recommendations listed for hygiene by the CRC Weed Management Guide are highlighted.
- Volume 25 Issue 4 - Annual Index 2010
- Volume 25 Issue 4 - Perceptions of Weeds in Changing Contexts. Land-Use Change, Landscape Value Change and Climate Change in South-Eastern Australia: Adaptation to Change in the Third Century of the Timeless Land
To perceive a weed is to ascribe meaning to the landscape where it occurs and ecosystem services required from that landscape. These perceptions change over time. In Australia, native vegetation has been transformed from something to be cleared to something of intrinsic value, and landscapes from bare palettes for new agronomy species to landscapes needing strict continental quarantine. We can now conceive of environmental weeds. Amidst these trends, the effects of global warming provide novel, all pervasive, pressures of environmental change at the continental scale. Under global climate change, southeastern Australia faces a warmer, drier, extreme-weather-event punctuated (e.g. fire and flood) future, whilst inhabitants face a socio-ecological-economic future that is both water and carbon-constrained and landscapes with profound legacies. Biophysical environments and related processes are changing, and will continue to change, including abundances and distributions of biota, including weeds. Prospective biological responses of weedy species provide part of our understanding, however, socio-ecological landscape changes, frequently ignored, are vital for a more complete appreciation of appropriate long-term responses. In the context of multiple uncertainties, adaptation to climate change, including land-use and management, is an increasing societal focus. Adaptation to climate change is vital for long-term sustainability and intergenerational landscape equity and includes the resilience of agricultural and post agricultural landscapes. Perceptions of assets and ecosystem services that we value and obtain from landscapes are changing trajectories of land-use, and response to climate change may accelerate these processes (e.g. carbonsequestration). Adaptation and mitigation (of CO2 emission) strategies converge in landscapes as society seeks to increase its resilience to climate change impacts. This contribution examines the interaction of these major fluxes in relation to historic land use and our perception of weeds. Responses to climate change will accelerate Australian society's on-going re-evaluation of landscapes and services they provide, including reevaluation of 'weeds' and consequent management strategies.
- Volume 25 Issue 4 - Mathematical Modelling of a New Weed Incursion and Its Control in Large Area Cropping Systems
Jayasuriya, Rohan T; van de Ven, Remy; Jones, Randall E
A mathematical model incorporating weed growth, dispersal and control is developed to represent the spread of a weed from a point source in cropping fields. This model allows the simulation of theoretical rates of weed spread and the examination of spatial distribution of a new weed infestation on a large regional scale. The model is cellular in structure, dividing space into discrete units. The starting point is with an initial population at a point source, such as might arise with the arrival of a newly invading species, an emerging sleeper weed or the first herbicide-resistant plants in an arable field. The location of this point source is set in the centre of the hypothetical grid field. From this starting point, the spread of weeds is modelled at annual intervals. Risk is a critical issue to this modelling; the weed spread functions being stochastic (with different probability distributions incorporating rare events in the dispersal process), and the weed control effort decision being probabilistic. Six case study weed spread simulations were undertaken to demonstrate the model's applicability to different weed incursions with differences in weed biology, rates of spread and to demonstrate the effects of weed search and control effort. The simulated model results are discussed in relation to a case study of awnless barnyard grass (Echinochloa colona) spread and its control in northern New South Wales, Australia.
- Volume 25 Issue 4 - The Flowering of Australia's Rainforests [Book Review]
- Volume 25 Issue 4 - In 'Vitro' Evaluation of the Antifungal Activity of Some Essential Oils on Post-harvest Fungal Pathogens of Tropical Fruits
Chuah, TS; Tan, YY; Ismail, BS
Essential oils derived from Citrus aurantifolia Swingle, Citrus limon (L.) Burm.f., Cymbopogon citratus (DC.) Stapf, Cestrum nocturnum L., and Michelia champaca Linn. were incorporated into potato dextrose agar and evaluated in vitro for fungistatic and fungicidal activity against Fusarium oxysporum (Fo), Fusarium oxysporum (Fo2) and Glomerella cingulata (Gc) isolated from the snake fruit, papaya and wax apple, respectively. Cymbopogon citratus oil exhibited the most activity against the fungi tested with minimum inhibitory concentrations (MIC) of 1.2, 0.8 and 1.0 mu L mL-1 against Fo, Fo2 and Gc respectively. Essential oils from M. champaca and C. nocturnum were moderately effective with fungistatic and fungicidal concentrations ranging from 0.8 to 6.4 mu L mL-1. Both citrus oils were found to be the least effective with the MIC ranging from 6.4 to 38.4 mu L mL-1. This preliminary study has revealed the potential use of the essential oil from Cymbopogon citratus against post-harvest fungal pathogens F. oxysporum and G. cingulata.
- Volume 25 Issue 4 - The Biology of Australian Weeds 56. 'Hymenachne amplexicaulis' (Rudge) Nees
Wearne, Lynise J; Clarkson, John; Grice, Anthony C; van Klinken, Rieks D; Vitelli, Joseph S
The review and analysis of the Australian weed commonly known as 'Olive' or Hymenachne amplexicaulis (Rudge) Nees is discussed. Details of its history, taxonomy, distribution, habitat, growth and development and management are highlighted.
- Volume 26 Issue 2 - Phytophagous Organisms Associated with the Woody Shrub 'Polygala Myrtifolia' (Polygalaceae) and Their Potential for Classical Biological Control in Australia
Adair, Robin J; Neser, Stefan; Stajsic, Val
Coastal ecosystems in southern Australia have been invaded by the South African shrub Polygala myrtifolia L. (Polygalaceae), leading to ecological disruptions and loss of biodiversity. Expansion of P. myrtifolia populations is expected unless effective containment or suppression activities are implemented. Low herbivory pressure in Australia compared to the species' native range is likely to have contributed to the invasion success of P. myrtifolia. Twenty-eight phytophagous organisms are recorded from P. myrtifolia in South Africa and six have potential as classical biological control agents, but require formal host specificity and impact evaluation. Further understanding of seed-bank dynamics and recruitment patterns of P. myrtifolia in Australia would contribute to the selection of suitable biological control candidates. Seeddestroying agents were not found on P. myrtifolia in South Africa, but additional survey effort is warranted as seed-destroying agents could alleviate conflicts of interest between environmental protection and the ornamental garden trade.
- Volume 26 Issue 2 - Association between Environmental Factors and the Occurrence of Six Fumitory Species ('Fumaria' spp. L.) in Southern-Eastern Australia
Norton, Gertraud M; Lemerle, Deirdre; Pratley, James E; Norton, Mark R
The occurrence of Fumaria as a weed in south-eastern Australian cropping systems is believed to have increased substantially in recent decades. To study this, a survey was conducted in contrasting regions of this zone, viz. southern New South Wales, mid-north South Australia. The survey analysed the pattern of occurrence of each of the six naturalized species found (Fumaria bastardii, F. densiflora, F. muralis, F. officinalis, F. parviflora and F. capreolata) and the natural environmental factors associated with their distribution. While five species were primarily found in agricultural environments, F. capreolata occurred exclusively in non-agricultural situations characterized by the presence of high soil organic matter. F. densiflora and F. bastardii were the most widespread and abundant species. F. officinalis was the rarest.
- Volume 26 Issue 2 - Root Regenerative Ability of Silverleaf Nightshade ('Solanum elaeagnifolium' Cav.) in the Glasshouse
Stanton, Rex; Wu, Hanwen; Lemerle, Deirdre
Silverleaf nightshade is considered amongst the worst weeds of crop and pasture systems in Australia due to its extensive root system. Cultivation may exacerbate the problem due to the regenerative capacity of the root system. Glasshouse experiments were conducted to determine the importance of cultivation in the spread of silverleaf nightshade by investigating the regenerative abilities of various root fragment lengths (1, 2.5, 5 and 10 cm) buried at three soil depths of 2.5, 5 and 10 cm. Regeneration occurred from root fragments as short as 1 cm, with shoot production increasing with root fragment length. Optimum burial depth was 5 cm for 1 and 2.5 cm root fragments, while 5 and 10 cm root fragments were equally prolific at stem production from the 2.5 cm burial depth. High levels of fragment mortality occurred in 1 cm fragments, with mortality levels significantly declining as fragment length increased. This research suggests that minimum tillage techniques should be encouraged on areas with silverleaf nightshade infestations. Implements should be thoroughly cleaned before leaving the infested area, as even short root fragments adhered to machinery are capable of starting a new infestation in a clean field.
- Volume 26 Issue 2 - Economic and Environmental Assessment of the Performance of Reduced Rates of Two Post-emergence Herbicides in an Arid Irrigated Production System of Central Australia: A Pilot Study
Hidalgo, Martin; Oliver, Glen; Raghu, S
The use of herbicides can add considerable costs to production practices on marginal land, and increase risks to environmental and human health. The relative performance of label and sub-label rates of the post-emergence herbicides (Amitrole T and Basta) and label rates of Roundup was compared within a benefit-cost analysis framework, in an arid irrigated production system in central Australia. Sub-label rates of Amitrole T and Basta were as effective at weed suppression as their label rates (LR); approximately 50% reduction in weed cover was recorded across the trial with both label and sub-label rates for both herbicides. The sub-label rates of Amitrole T (75% LR and 65% LR) and Basta (75% LR) had a statistically similar economic benefit-cost ratio as their corresponding LRs, and the LR of Roundup. The equivalence of Basta's sub-label rate in terms of economic efficiency is even more noteworthy if one takes into account that significantly lower amounts of the herbicide needed to be applied to achieve the level of weed suppression obtained using the label rate of Roundup. Our results suggest ways to improve the economic and environmental efficiencies of herbicide use in the arid, irrigated production systems of central Australia.
- Volume 26 Issue 2 - Seed Dynamics of the Invasive Geophyte 'Lachenalia reflexa' Thunb. in South-West Australia
Brown, Kate; Paczkowska, Grazyna
Geophytes from South Africa's Cape Province are a particularly serious group of invasive plants in south-west Australia. They threaten natural biodiversity across the region, invading relatively undisturbed habitat and displacing native plant communities. Their success as invaders has been linked to rapid and profuse seedling germination, however studies on a number of species have documented short lived soil seed banks. This study investigates seed viability and soil seed bank persistence of the Cape geophyte, Lachenalia reflexa Thunb. where it is invading Banksia woodlands on the Swan Coastal Plain, Western Australia.
- Volume 26 Issue 2 - Predicting the Cost of Eradication for 41 Class 1 Declared Weeds in Queensland
Panetta, FDane; Csurhes, Steve; Markula, Anna; Hannan-Jones, Martin
The feasibility of state-wide eradication of 41 invasive plant taxa currently listed as 'Class 1 declared pests' under the Queensland Land Protection (Pest and Stock Route Management) Act 2002 was assessed using the predictive model 'WeedSearch'. Results indicated that all but one species (Alternanthera philoxeroides) could be eradicated, provided sufficient funding and labour were available.
- Volume 26 Issue 4 - The flowering of Australia's rainforests [Book Review]
Review(s) of: The flowering of Australia's rainforests, by Geoff Williams and Paul Adam, Published by CSIRO Publishing in 2010, ISBN 9780643097612, colour plates, 216 pages, hard cover. Price $A99.95.
- Volume 26 Issue 4 - Mistletoes of Southern Australia [Book Review]
Review(s) of: Mistletoes of Southern Australia, by David M. Watson, illustrations by Robyn Hulley, Published by CSIRO Publishing in 2011, ISBN 9780643095939, colour, 200 pages, soft cover. Price $A49.95.
- Volume 26 Issue 4 - Subject index
- Volume 26 Issue 4 - Planting for wildlife - a practical guide to restoring native woodlands [Book Review]
Review(s) of: Planting for wildlife - a practical guide to restoring native woodlands, by Nicola Munro and David Lindenmayer, Published by CSIRO Publishing in 2011, ISBN 9780643103122, colour, 96 pages, soft cover. Price $A39.95.
- Volume 26 Issue 4 - Author index
- Volume 26 Issue 4 - Wetland weeds - causes, cures and compromises [Book Review]
Review(s) of: Wetland weeds - causes, cures and compromises, by Nick Romanowski, Published by CSIRO Publishing in 2011, ISBN 9780643103955, colour, 184 pages, soft cover. Price $A49.95.
- Volume 26 Issue 4 - Australian weed societies - beyond the millennium
The second Council of Australian Weed Science Societies (CAWSS) Oration delivered by A. Nelson Johnston at the sixth Australian Weeds Conference in 1981 reviewed the history of Australian weed societies, outlined the challenges they faced and commended actions to the audience. Advances in technology and changes in social attitude during the intervening 30 years have created new challenges. Societies face the additional burden of their administrative committees relying on voluntary participation in an era where weeds workers are increasingly time poor as their workloads increase.
- Volume 26 Issue 4 - Review of the outbreak threshold for Queensland fruit fly ('Bactrocera tryoni' Froggatt)
Dominiak, Bernard C; Daniels, David; Mapson, Richard
Fruit flies cause losses in horticultural produce across the world and are a major quarantine concern for most countries. Queensland fruit fly (Qfly) is a native to Australia and is also present in a small number of Pacific Island countries. The detection of Qfly in recognized pest free areas triggers quarantine restrictions from domestic and international markets. In Australia, the detection of five male flies has been taken to indicate an outbreak (i.e. unacceptable risk). Matching the domestic standard, many countries have accepted the 5-fly limit as a quarantine threshold. But some other countries have set the detection of two male flies, or even a single fly, as the threshold for an outbreak. This different standard creates an administrative complexity for exporters and trade regulators. In this paper, we review the published science covering the impediments to pest establishment. Outbreak data from Victoria and New South Wales during 2007 and 2009 are reviewed in relation to the 2-fly and 5-fly thresholds. Large volumes of fruit have been traded within Australia and internationally based on the 5-fly threshold without incident and there is no evidence that the 2-fly threshold is more appropriate. While Qfly is recognized as being capable of longer distance dispersal than some other fruit fly species, it is also recognized as a poor colonizer. The 5-fly threshold is proposed as the most appropriate threshold for imposition of quarantine restrictions and is recommended as a universal standard for harmonization of quarantine regulations.
- Volume 26 Issue 4 - Efficacy of some botanical extracts against 'Callosobruchus maculatus' in cowpea seeds and an evaluation of their toxicity
Ahmed, SI; Gazzy, AA
Extracts of seven plant species were tested under laboratory conditions for their ability to protect cowpea seeds against the insect 'Callosobruchus maculatus'. The insect was reared and tested on whole cowpea seeds with respect to the adult's mortality, hatchability of laid eggs and emergence. Gas chromatography-mass spectrometry (GC-MS) analysis was carried to identify the chemical components of the most effective plant extracts against 'C. maculatus'. Furthermore, the safety of the most effective plant extracts was evaluated with respect to biochemical and histological changes in rats. The results revealed that 'Euonymus japonicus' and 'Cassia fistula' extracts were the most effective against 'C. maculatus' with respect to insect mortality and progeny relative to the control. The GCMS analysis of these extracts showed the presence of different bioactive compounds. These extracts also showed low toxicity on treated rats. The results suggest that these extracts may be a safe alternative to insecticides.
- Volume 26 Issue 4 - Scenario tree risk analysis of zero detections and the eradication of yellow crazy ant ('Anoplolepis gracilipes' (Smith)), in New South Wales, Australia
Dominiak, BC; Gott, K; McIver, D; Grant, T; Gillespie, PS; Worsley, P; Clift, A; Sergeant, ESG
Yellow crazy ant (YCA) Anoplolepis gracilipes (Smith) is ranked among the world's worst invasive species. Following the detection of this ant on Goodwood Island in northern New South Wales, Australia in 2004, an eradication program was initiated. The last detection was made in January 2006 and the declaration of freedom from the pest was made in January 2008, based on the traditional two-year period without a detection. However, although this eradication criteria is widely used, the two year timeframe is an arbitrary period with little or no scientific basis. Here, in addition to describing the eradication, we present a scenario tree analysis of zero detections to predict the level of confidence that the pest would have been detected if it was still present. Following a two year period with no detections, the scenario tree analysis indicated that there was a probability of absence of 0.999 998 under an assumed incursion pressure of one incursion every ten years. After eradication, the scenario tree analysis also indicated that as few as 20 randomly located visual inspections in the high risk area every three months was sufficient to maintain >0.95% probability of freedom. The analysis was also used to assess the merits of different surveillance techniques.
- Volume 26 Issue 4 - The biology of Australian weeds 58. 'Baccharis halimifolia' L.
Sims-Chilton, Nikki M; Panetta, FDane
Review(s) of: The genus name Baccharis is after the Greek bakkaris, an oil producing plant (later called 'Celtic valerian') (Parsons and Cuthbertson 1992). The species name halimifolia is derived from the Greek alimos meaning 'seas' and the Latin folium meaning 'leaf' (Parsons and Cuthbertson 1992). Baccharis halimifolia L. belongs to the family Asteraceae which is the largest family of flowering plants, comprised of over 1100 genera and 19 000 species (Zomlefer 1994). Baccharis is a large genus, comprised of over 400 species (Mahler and Waterfall 1964, Zomlefer 1994) distributed over seven geographical areas: Brazil, Andes Mountains, Andes-Patagonia, Guyanarum, south-eastern Brazil, Mexico (including western United States) and the Antilles (including the eastern United States) (Boldt 1989). In Australia, B. halimifolia is most commonly known as groundsel bush. 'Groundsel' refers to the groundsel-like flowering heads, as in plants in the Senecio genus (Parsons and Cuthbertson 1992). In its native region it is often referred to as saltbush (Stevenson 1969, Proffitt et al. 2005), groundsel tree (Altfeld and Stiling 2006), sea myrtle (Caccamise 1977, Dickens and Boldt 1985) and eastern baccharis (Adlerz 1980).
No Issue Number
- Volume 27 Issue 2 - Plant protection quarterly - publishing now and in the future
Johnson, Stephen B
- Volume 27 Issue 2 - The Biology of Australian weeds 60. 'Sagittaria platyphylla' (Engelmann) J.G. Smith and 'Sagittaria calycina' Engelmann
Adair, RJ; Keener, BR; Kwong, RM; Sagliocco, JL; Flower, GE
Sagittaria (Alismataceae) are aquatic herbs with 40 described species and eight infraspecific taxa. The genus has a natural distribution throughout North and South America, Europe, Africa and Asia, but species diversity is highest in the neotropics, temperate North America and eastern Asia. The name Sagittaria is derived from the Latin word sagitta, meaning 'arrow', which refers to the arrowhead shape of the emergent leaf blades produced by many species.
- Volume 27 Issue 2 - Effect of fungicides in vitro and on detached berries on control of coffee berry anthracnose caused by Colletotrichum Acutatum and C. Gloeosporioides
Kenny, MK; Galea, VJ; Price, TV
Potential fungicides for the control of coffee berry anthracnose in Papua New Guinea were identified. Sixteen fungicides were tested in vitro at 100 mug mL-1 a.i. for their inhibition of spore germination and mycelial growth of Colletotrichum acutatum Simmonds and C. gloeosporioides (Penz.) Penz. and Sacc. isolates from anthracnose infected coffee berries in Papua New Guinea. The most effective fungicides (triademorph, captan, thiram, propiconazole and copper oxychloride) were tested further at concentrations between 0-12800 mg L -1 a.i. Thiram at 200 mug mL-1 a.i. was the most effective fungicide followed by propiconazole. Detached coffee berries were not infected by C. acutatum and C. gloeosporioides when treated with suspensions of the five fungicides at the in vitro rates that totally inhibited spore germination and mycelial growth. The results showed that thiram at 200 mug mL-1 a.i. and propiconazole are the best fungicides for field testing of control of anthracnose on coffee in Papua New Guinea.
- Volume 27 Issue 2 - A preliminary report on the potential resistance of a soapbush ('Clidemia hirta' (L.) D. Don) biotype to metsulfuron-methyl in an oil palm plantation in Jerantut, Malaysia
Ramadzan, AMN; Ismail, BS; Chuah, TS
The present study was undertaken to confirm the presence of a metsulfuronmethyl resistant (R) biotype of Clidemia hirta (L.) D. Don in an oil palm plantation in Jerantut, compared to a susceptible (S) biotype found in Jengka, Pahang, Malaysia. The first study was conducted as an on-site field spraying experiment using several concentrations of metsulfuron- methyl, whereas the second was carried out in the laboratory using 10 mm diameter leaf discs immersed in several metsulfuron-methyl concentrations. The third study was done in a greenhouse where the growth of the R and S biotypes were observed under two different light intensities. For the on-site field experiment, spraying at the recommended dosage [30 g active ingredient (a.i.) haˉ ] gave 100% control of the S biotype, whereas the R biotype showed full recovery (0% control) 56 days after treatment with metsulfuronmethyl at levels as high as eight times (240 g a.i. haˉ ) the recommended rate. From the comparison of the ED50 of the leaf discs, the laboratory test showed that the resistant biotype was 16-times more resistant to metsulfuron-methyl than the susceptible biotype. The greenhouse experiment indicated that, relatively, the R biotype expressed slower growth in the upper part growth measurements in plant height, total leaf area, stem mass ratio and relative biomass growth ratio but in contrast, showed greater allocation to root mass compared to S biotype. Both biotypes of C. hirta planted under high light intensity showed slower growth in plant height, relative stem length growth rate, total leaf area, leaf area ratio, leaf mass ratio and stem mass ratio, but allocated more mass to root and relative biomass growth rate.
- Volume 27 Issue 2 - Control of alligator weed with herbicides: A review
Dugdale, Tony M; Champion, Paul D
Alligator weed (Alternanthera philoxeroides (Mart.) Griseb.) is a widespread weed that is difficult to control. Despite many published accounts relating to its control there is no published review on herbicide control of alligator weed. This paper describes the biology and impacts of alligator weed and the efficacy of herbicides and herbicide-based control programs used against it.
- Volume 27 Issue 2 - 'Mesembryanthemum guerichianum' pax (Aizoaceae): A weedy alien species new to Australia
Chinnock, RJ; Stajsic, V; Brodie, CJ
A newly discovered alien species of Mesembryanthemum, M. guerichianum Pax, is reported for Australia for the first time. It occurs in South Australia, New South Wales and Victoria. It has been overlooked in the past presumably having been mistaken for the widespread M. crystallinum L. which it is closely related to. A detailed account of the species based on Australian populations is given including a description, distribution, ecology, and a brief discussion is provided on current views on the generic limits of Mesembryanthemum. A key to the species of Mesembryanthemum in Australia is provided, and the species is compared with M. crystallinum.
- Volume 27 Issue 3 - Plant protection quarterly and the future of plant protection research in Australia
Johnson, Stephen B
- Volume 27 Issue 1 - Plant protection quarterly - our scope, audience, history and future
Johnson, Stephen B
- Volume 27 Issue 1 - The biology of Australia weeds 59. 'Clidemia hirta' (l.) D. Don.
Breaden, RC; Brooks, SJ; Murphy, HT
Clidemia hirta (L.) D. Don (syn. Melastoma hirta L.) is in the family Melastomataceae, tribe Miconieae. The Miconieae comprise approximately 1800 species in 19-23 genera and are exclusively neotropical (Michelangeli et al. 2008). The genus Clidemia, established by David Don in 1823, currently contains about 180 species (Gleason 1939, Manickam et al. 2000, Kriebel and Almeda 2009) with new species still being described, particularly from Costa Rica and Panama (Kriebel and Almeda 2009). The species name hirta is derived from the Latin word for 'hairy' or 'scrubby'.
- Volume 27 Issue 1 - Seasonal abundance of thrips (thysanoptera) in capsicum and chilli crops in South-East Queensland, Australia
Walsh, Bronwyn; Maltby, John E; Nolan, Brendan; Kay, Iain
Thrips can be important pests of capsicum and chilli crops, causing damage through their feeding and by vectoring viral diseases. As different species vary in their ability to transmit viruses and in their susceptibility to insecticides, it is important to know which species are present in a crop. The seasonal occurrence of thrips in capsicum and chilli crops in the Bundaberg district of south-east Queensland was investigated from July 2002 to June 2003. Fifty flowers were collected weekly from crops on seven farms and the adult thrips extracted and identified. Thrips palmi Karny and Frankliniella occidentalis (Pergande) were collected in the greatest numbers, with T. palmi predominant in autumn crops (March to July) and F. occidentalis predominant in spring crops (August to November). Pseudanaphothrips achaetus (Bagnall) was common, while Thrips tabaci Lindeman, Thrips imaginis Bagnall and Frankliniella schultzei (Trybom) were collected in low numbers.a
- Volume 27 Issue 1 - Changes in the distribution and density of bitou bush ('chrysanthemoides monilifera' subsp. 'rotundata' (DC.) T.Norl.) In eastern Australia
Hamilton, Mark; Winkler, Marion A; Cherry, Hillary; Downey, Paul O
Bitou bush (Chrysanthemoides monilifera subsp. rotundata (DC.) T.Norl.) is a South African shrub that has invaded large areas of coastal south-eastern Australia. It is widespread along the coast, where it negatively impacts native plants and ecological communities. Detailed spatial information is critical for making informed management decisions, particularly to assist in setting on-ground priorities and allocating resources, and to evaluate the effectiveness of weed management. The distribution of bitou bush was mapped previously in New South Wales; this paper presents an updated assessment of the distribution and density of bitou bush in Australia for 2008. The data were collated from a range of land managers and community groups, and analysed to determine area, density and spatial changes in bitou bush distribution. Mapping data were also analysed with respect to conservation areas in New South Wales, and national bitou bush containment lines, established to prevent northern and southern spread. The total area of bitou bush in Australia increased by 20% since 2001; 83% of the increase consisted of infestations with less than 10% cover. However, this spread has been offset by a 43% reduction in infestations with greater than 40% cover. Some of the overall increase in area may be attributed to a more comprehensive survey methodology, as this study may have captured sparse infestations that were not recorded in previous surveys. The distribution of bitou bush was found to be highly coastal, with 90.3% of bitou bush within 2.5 km of the coastline. The area of bitou bush in conservation areas in New South Wales decreased by 21%, including a 56% decrease in infestations with greater than 40% cover. Management in national containment zones has successfully restricted bitou bush spread and significantly reduced its density in these nationally significant areas. Continued support for strategic control programs will ensure the spread of bitou bush in Australia is contained.
- Volume 27 Issue 1 - Chemical analysis of male annihilation blocks used in the control of queensland fruit fly 'bactrocera tryoni' (froggatt) in New South Wales
Dominiak, Bernard C; Nicol, Helen I
The male annihilation technique (MAT) is a chemical control method designed to deplete the males available for mating in a population and thus break the reproductive cycle. In the New South Wales fruit fly control program, caneite has been used as a carrier for the lure and pesticide in MAT blocks for many years. In this paper, MAT blocks containing cuelure as an attractant and malathion as a toxicant were manufactured using two methods, namely bag immersion and roller painting, as part of the control program for Queensland fruit fly in New South Wales between September 1998 and June 2000. These blocks were sampled from storage and the field, along with historical blocks in the field deployed before the current study period. Chemical analyses of these three block types were conducted for malathion, cuelure, and raspberry ketone (a breakdown product of cuelure). There was significantly more cuelure and malathion in blocks made by the bag method than the roller method and in historical blocks. The bag method resulted in chemical concentrations closer to the desired standards. There were no significant differences between the three methods in block weight or in level of raspberry ketone. Cuelure levels declined more quickly than malathion although both chemicals were found in all blocks. For the analysis within samples, there were few significant correlations between raspberry ketone and other parameters, but there were many significant correlations between cuelure, malathion and the block weight.
- Volume 27 Issue 1 - Herbicide resistance frequencies in ryegrass ('Lolium' spp.) And other grass species in Tasmania
Broster, JC; Koetz, EA; Wu, H
In January 2010 a random survey was conducted to determine the frequency of herbicide resistance in populations of Lolium spp. (ryegrass), Avena spp. (wild oat), Bromus diandrus Roth. (brome grass) and Hordeum lepinorum Link (barley grass) across the cropping region of Tasmania, Australia. A total of 84 paddocks were surveyed with 80 containing the aforementioned weed species, resulting in the collection of 76 ryegrass, 16 wild oat, seven brome grass and five barley grass samples. These samples were then screened against the most commonly utilised herbicide groups for annual grass control in Australia. Ryegrass resistance frequencies were highest to aryloxyphenoxypropionate (18%) and sulfonylurea (24%) herbicides with lower incidences of resistance to cyclohexanedione (1%), imidazolinone (7%) and dinitroaniline (1%) herbicides. Sixty four percent of ryegrass samples tested against five herbicide groups (aryloxyphenoxypropionate, cyclohexanedione, sulfonylurea, triazine and dinitroaniline) were susceptible to all herbicides, 27% were resistant to one herbicide only, 7% to two herbicide groups and one sample was resistant to three herbicide groups. In the other species collected, resistance was found only to aryloxyphenoxypropionate herbicides with two wild oat and one barley grass samples exhibiting resistance to herbicides in this group. The frequency of resistance observed in screened populations in this survey is much lower than that found in recent surveys of southern Australian cropping regions. A lower frequency of observed herbicide resistance in Tasmania, combined with our ability to use the knowledge gained from 20 years of herbicide resistance management, should result in a predictably slower spread of herbicide resistant grass weeds than experienced in many other regions of Australia.
- Volume 27 Issue 1 - Biological control of weeds in Australia [Book Review]
Review(s) of: Biological control of weeds in Australia, edited by Mic Julien, Rachel McFadyen and Jim Cullen, ublished by CSIRO Publishing 2012, hardback, colour, 648 pages, price $180.00, ISBN 9780643099937.
- Volume 27 Issue 1 - Controlling invertebrate pests in agriculture [Book Review]
Review(s) of: Controlling invertebrate pests in agriculture, by Jessica Page and Paul Horne, Published by CSIRO Publishing 2012, paperback, black and white, 128.
- Volume 27 Issue 1 - Reducing the impacts of development on wildlife [Book Review]
Review(s) of: Reducing the impacts of development on wildlife, by James Gleeson and Deborah Gleeson, Published by CSIRO Publishing 2012, paperback, colour, 248 pages price $89.95, ISBN 9780643100329.
- Volume 27 Issue 3 - Cabbage-centre grub, 'hellula hydralis guenee', not resident in Tasmania
This paper collates information about cabbage-centre grub, Hellula hydralis Guen e (Lepidoptera: Pyralidae) to indicate that this pest is not established in Tasmania despite frequent immigration from mainland Australia and the presence of suitable host plants in Tasmania. Light trap data demonstrates the erratic but frequent occurrence of cabbage-centre grub adults at Devonport, Tasmania. Examples of several probable migrations are illustrated by back air trajectory analysis coinciding with several large catches in one permanent light trap at Devonport. Substantial inspection of crops by many entomologists and agronomists over decades has never detected immature stages of this pest in Tasmania. A day-degree development model for this pest is not available so that the suitability of the Tasmanian climate cannot be assessed by that method but records of the pest breeding as far south as Victoria do exist. The results provide one example to biosecurity entomologists of a pest that repeatedly fails to establish, even ephemerally, in Tasmania despite frequent introductions and the presence of host plants and a mainland distribution extending into Victoria. It also demonstrates how the status of a pest in a region can be misconstrued if merely assessed by records of adult captures, which dominate records for many insects in official databases such as the Australian Plant Pest Database of Plant Health Australia.
- Volume 27 Issue 3 - Fungi and phytophagus arthropods associated with Himalayan honeysuckle ('leycesteria formosa' wall.) In North-east Victoria
Adair, RJ; Cunnington, J; Kulkarni, S
The invasive shrub Leycesteria formosa Wall. is problematic in natural ecosystems in south-east Australia. In 2009, a population at Bruarong in north-east Victoria was found to be in decline. A range of fungi were isolated from the foliage, stems and roots of L. formosa, but these were considered to be either endophytes, saprophytes or weak pathogens. There was no indication of bacterial infections and no viruses were detected. The mite Tetranychus urticae Koch. was found to damage foliage and reproductive structures and induce premature defoliation of plants in late summer and autumn. Tetranychus urticae may have a role in the biological suppression of L. formosa in natural ecosystems as an augmentative agent.
- Volume 27 Issue 3 - An overview of pre-border weed risk assessment and post-border weed risk management protocols
The need for weed risk assessment has grown worldwide with increasing international trade and travel as well as new uses for plants such as biofuels. Australia has been at the forefront in developing a screening system for plants that has been adopted in other countries. However, refinements and improvements in the system have been suggested. For species that have already invaded, a range of management options are available, depending on the risk posed and the feasibility of control. Jurisdictions with noxious plant laws inherently have some form of risk assessment, but this, and potential management strategies, are often not explicit nor well documented. In Australia, a National Post- Border Weed Risk Management Protocol (Standards Australia 2006), is currently being revised. It provides guidelines to prioritise species in which relative risk and feasibility of control are contrasted to arrive at suggested management actions. Future developments of the protocol are likely to take into account widespread weeds, contentious species and uncertainty in its various forms.
- Volume 27 Issue 3 - Style guide for plant protection quarterly
Plant Protection Quarterly (PPQ) is an Australian peer reviewed journal which enjoys an international reputation for publishing original basic and applied research papers on all aspects of plant protection. Manuscripts dealing with the protection of economic, environmental and societal values from weeds/invasive plants, pathogens and disease, and pests including insects, nematodes and other predators will be considered for publication. This includes the management of these organisms through prevention, eradication, containment and asset protection activities which may require quarantine, surveillance, chemical, physical or cultural management techniques and/or biological control agents.
- Volume 27 Issue 4 - The biology of Australian weeds 61. 'Polygala myrtifolia' L.
Adair, RJ; Shackleton, A; Stajsic, V; Gajaweera, R
Polygala myrtifolia L., Sp. Pl. 2: 703 (1753) Polygala is Greek derived from polys meaning 'much' and gala meaning 'milk'. The genus is named because some species reputedly promote the secretion of milk when eaten by stock. The specific epithet myrtifolia refers to similarity to myrtle leaves.
- Volume 27 Issue 4 - Weed management paradigms and the needs for research
Johnson, Stephen B
- Volume 27 Issue 3 - Life in a gall; What a plant knows - a field guide RG Richardson, Meredith to the senses [Book Review]
Review(s) of: Life in a gall, by Rosalind Blanche, Published by CSIRO Publishing 2012, small paperback, colour, 80 pages, price $29.95. ISBN 9780643106437; by Daniel Chamovitz Published by Scribe Publications 2012, b/w, paperback, 288 pages, price $18.99, ISBN 9781921844638.
- Volume 27 Issue 4 - Allelopathy - a fancy name or a potential weed management tool'
Australian agriculture is very dependent on herbicides for weed control and the maintenance of soil structure through no-till farming. These chemicals have been highly effective but their efficacy has been under threat for some time through the evolution of herbicide resistance. If herbicide technology fails, Australian agriculture will be poorly placed. Options need to be considered now so that there are alternatives, or at least to support the maintenance of current practices. Allelopathy is one of the possible options and its potential role is canvassed here. However it will require a different paradigm to the one currently underpinning chemical farming.
- Volume 27 Issue 4 - Just how bad are coastal weeds: Assessing geo-ecopsycho- socio-economic impacts
Cousens, Roger; Williams, Kathryn; Kennedy, David; Maguire, SGrainne
This project is a multidisciplinary project documenting the various ecological, physical, social and economic impacts of coastal weeds and their interactions. We have documented the history of the major invasive species using herbarium records and documents. A comprehensive literature review of the interactions between weeds and other aspects of the beach environment has been completed and we are using this to "map out" these interactions. This understanding of interactions is being enriched through field observations being made by around 150 people volunteer 'citizen scientists' throughout southern Australia reporting on interactions between animals and weeds. Social impacts of weeds are being explored through surveys and interviews.
- Volume 27 Issue 4 - Australia's poisonous plants, fungi and cyanobacteria [Book Review]
Review(s) of: Australia's poisonous plants, fungi and cyanobacteria, by Ross McKenzie, Published by CSIRO Publishing 2012, hardback, colour, 976 pages, price $195.00 ISBN 9780643092679.
- Volume 27 Issue 4 - Biodiversity priorities for widespread weeds [Book Review]
Review(s) of: Biodiversity priorities for widespread weeds, by Department of Primary Industries and Office of Environment and Heritage, New South Wales, Published by NSW Department of Primary Industries 2011, ISBN 978 1 74256 086 1.
- Volume 27 Issue 4 - Annual index 2012 volume 27
- Volume 27 Issue 4 - Forthcoming events
- Volume 27 Issue 4 - A global compendium of weeds - 2nd edition [Book Review]
Johnson, Stephen B
Review(s) of: A global compendium of weeds - 2nd edition, by Rod Randall, Published by and available from the Department of Agricture and Food, Western Australia 2012, 1124 pages. ISBN 978-0-646-57878-1.
No Issue Number
- Volume 28 Issue 3 - Making the move from traditional to contemporary weed management
This paper is an account of how Far North Coast Weeds, a Weeds County Council in the Far North Coast region of New South Wales, transitioned from a traditional weed management model to a contemporary weed management approach. This area of New South Wales has the highest biodiversity values in the State and includes all the right climatic and geographic ingredients that allow it be a true garden of Eden for weed domination. Operating in one of the most complex and challenging weed management environments in Australia this County has actively adopted and espoused the goals of the New South Wales Invasive Species Plan in all facets of its business planning and service delivery. Through sheer determination, innovation and belief this approach has inspired stakeholders who were once negative and disengaged to embrace and unite to tackle weeds strategically to return the highest return on investment and the greatest public benefit.
- Volume 28 Issue 3 - Don't let the truth get in the way of a good story. The declaration of weeds that affect the environment started in 1907 in New South Wales
Johnson, Stephen B
It is often claimed that the declaration and management of weeds that impact on the environment is a relatively recent occurrence. This story has shaped the development of legislation, policy and investment in New South Wales weed management programs. Unfortunately, like most good stories, it is not entirely accurate. To claim that the management of weeds that impact environment values in New South Wales is only a recent development is to ignore the historical record. In saying this, there is some evidence to suggest that weeds that impact on environmental values are now better managed in New South Wales, particularly under the Noxious Weeds Act 1993 and the Threatened Species Conservation Act 1995. This paper examines the first 25 years of weed declarations in New South Wales comparing these to current declarations. The paper summarises in excess of 1300 and 2100 declarations under the Local Government Act 1906 and the Local Government Act 1919 respectively. Weeds declared in New South Wales during the period 1907-1931 affected both primary production and the environment. The importance of some weeds then managed has waned such that stinkwort (Dittrichia graveolens L. Greuter) and inkweed (Phytolacca octandra L.) are of little current concern, and are now not declared. In contrast, many weed declarations are similar to those today, for example Bathurst and Noogoora burr (Xanthium spinosum L. and X. occidentale Bertol., respectively). In such cases we need to ask whether the battle against these weeds over the last 105 years has been successful.
- Volume 28 Issue 3 - Robotic aircraft and intelligent surveillance systems for weed detection
Hung, Calvin; Sukkarieh, Salah
This paper presents a summary of the autonomous weed detection research and development program at the Australian Centre for Field Robotics (ACFR) over the past seven years. The ACFR has used various aerial robots on various detection and mapping projects, targeting weeds including prickly acacia (now Vachellia nilotica (L.) P.J.H.Hurter and Mabb.), parkinsonia (Parkinsonia aculeata L.), mesquite (Prosopis pallida (Willd.) Kunth), wheel cacti (Opuntia robusta J.C.Wendl. ex Pfeiff.) and salvina (Salvinia molesta D.S.Mitch.) in various parts of Australia. The algorithm research at ACFR leads to various intelligent detection and mapping software systems for accurate terrain mapping, vegetation segmentation and detection of different invasive species.
- Volume 28 Issue 3 - A success story: The Cape broom psyllid, 'Arytinnis hakani' Loginova
Cape broom (Montpellier broom), Genista monspessulana (L.) L.A.S.Johnson, is a leguminous shrub of Mediterranean origin. It is widespread in southern Australia infesting over 600 000 ha. Cape broom forms dense thickets in bushland, forestry, grassland, pastures, and recreation areas. It is a newly declared Weed of National Significance (WoNS). The psyllid, Arytinnis hakani Loginova was released in September 2010 at Captains Flat on the southern tablelands of New South Wales. Within eight months the psyllid had dispersed widely to a distance of 1.3 km from the nearest release point with shrubs being severely defoliated and producing few flowers and seed pods. Within 19 months, many Cape broom shrubs were dead.
- Volume 28 Issue 3 - Biosecurity legislation, dispersal of local weeds and the tort of private nuisance
Following the Australian Government, many Australian states are considering replacing a raft of biosecurity laws with a single biosecurity statute: for example Queensland is much more advanced in this process than New South Wales. Biosecurity law is generic by nature and relies on a number of all encompassing definitions. Biosecurity law can also apply to noxious weeds but would be limited to species that pose a significant threat to the economy, environment and/or community. This type of law aims to prevent or limit the impacts of external costs created by the spread of weeds (or other pests or disease) to new areas. It is inefficient when used to limit the dispersal of established local weeds. Civil tort law, however, may offer a remedy to landholders harmed by ongoing and uncontrolled dispersion of such local weeds.
- Volume 28 Issue 1 - Why should you publish in Plant Protection Quarterly?
Johnson, Stephen B
- Volume 28 Issue 1 - 'Daphne laureola' L. (Thymelaeaceae): A weedy alien species new to Australia
Baker, Matthew L
The alien species, Daphne laureola L., is reported as naturalised in Australia for the first time. It has been found at Fern Tree, Tasmania, on the foothills of Mount Wellington, where it has been spread, most likely by birds, from garden plant ings into adjacent bushland. This also represents the first instance of the genus Daphne L. being naturalised in Australia. A detailed account is provided, including a description, notes on its distribution and ecology and a comparison with other species similar in appearance.
- Volume 28 Issue 1 - Weed emergence as affected by soil disturbance and moisture in a controlled environment
Calado, Jose MG; Basch, Gottlieb; Barros, Jose FC; de Carvalho, Mario
Emergence of weeds is influenced by disturbance of the top soil layer which, in general, creates favourable environ mental conditions for the germination of seeds and consequent plant emergence. This study reports the influence of soil disturbance on the emergence of weeds under different soil moisture levels. The experiments were carried out under controlled environment conditions, using rings containing undisturbed soil cores collected from the top soil layer (0-2.5 cm and 0-5.0 cm depths) of a Luvisol. The treatments comprised two depths and four moisture levels in disturbed and undisturbed soil. The results showed that both moisture level and soil disturbance greatly influence weed seedling emergence. Emerged seedlings in the disturbed soil, which had been subject to a moisture level greater than or equal to two thirds field capacity, was higher in number than in the undisturbed soil. However, soil subject to saturation followed by desiccation produced fewer seedlings when the soil was disturbed.
- Volume 28 Issue 1 - Surveillance for Asian gypsy moth ('Lymantria dispar Asiatica' L.) Between 2005 and 2012 in New South Wales, Australia
Dominiak, Bernard C; Gillespie, Peter S; Subasinghe, Ranjith
Gypsy moths have the capacity to cause severe defoliation to forestry, amenity trees and horticultural crops. Gypsy moths are transported as adults or eggs on sea freighters and may infest countries previously free of gypsy moth. Australia has remained free from gypsy moths but must continually use surveillance to demonstrate its freedom. A wide range of climate and host trees make parts of Australia susceptible to incursions and the establishment of gypsy moths. Surveillance for gypsy moths (Lymantria dispar L.) was undertaken during the months of October to March on a yearly basis from 2005 to 2012 in New South Wales using pheromone traps and that were inspected fortnightly. No Asian gypsy moths were found, but a native moth (L. antennata Walker) was detected.
- Volume 28 Issue 1 - A history of forecasting outbreaks of the southern armyworm, 'Persectania ewingii' (lepidoptera: noctuidae) in Tasmania
Light trap data is used to illustrate a successful history of forecasting December outbreaks of Persectania ewingii (Westwood), southern armyworm caterpillars in Tasmanian cereal crops and pasture between 1954 and 2006. Spring catches varied by 2-3 orders of magnitude and large catches always preceded outbreaks. Thresholds indicating likely outbreaks were determined empirically and varied from trap to trap, being a spring catch of 50 moths for traps at Elliott and Ouse, but only eight for the trap at Cressy. Unusual early or late season outbreaks are also discussed. Comparisons among several traps in a network operated by the state agricultural agency are given and indicate considerable correlation. Outbreak years since 1912 are listed along with notes on early records of the pest. The identity of the species likely to have caused outbreaks is clarified as southern armyworm and common armyworm by examining light trap data and historic pest records to exclude several other Hadeninae or Spodoptera species.
- Volume 28 Issue 1 - A Travellers Flora. A guide to familiar plants, along roadsides, in fields and forgotten places [Book Review]
Johnson, Stephen B
Review(s) of: A Travellers Flora. A guide to familiar plants, along roadsides, in fields and forgotten places, by Bruce A. Auld, (Professor of Plant Ecology at Charles Sturt University, Orange), Published by and available from Samara, 347 Convent Lane, Borenore, NSW 2800, Australia, Tel +61 (0)2 6365 2394, Full colour, 180 pages, 230 x 156 mm, price $29.95 ISBN 9780646901169.
- Volume 28 Issue 3 - Determining the efficacy of the herbicides endothal and diquat on the aquatic weed sagittaria in irrigation channels
Clements, Daniel; Dugdale, Tony M; Hunt, Trevor D
Sagittaria (Sagittaria platyphylla (Engelmann) J.G. Smith) is an emergent aquatic weed that has invaded irrigation systems throughout northern Victoria and southern New South Wales. In earth irrigation channels and drains it impedes water flow, reducing hydraulic capacity and limiting the efficiency of modernised water delivery systems. Currently, there are limited effective control options for sagittaria. This paper describes a field trial to determine the effectiveness of winter applications of the herbicides endothal and diquat in controlling sagittaria, in static irrigation channels. Endothal provided excellent control of both the emergent and submerged forms of sagittaria during winter conditions. Diquat, with and without a gelling agent, was ineffective.
- Volume 28 Issue 3 - Recent advances in galenia control
The options available to control galenia (Galenia pubescens (Eckl. and Zeyh.) Druce) in Australia are restricted to two herbicide treatments and physical removal. This may limit the success of control options in limited situations. Furthermore, regular control with few herbicides may result in herbicide resistant populations. A total of six experiments were conducted to investigate the potential herbicide treatments for galenia control. Many new herbicide treatments were considered worthy of obtaining label registrations or off-label permits via the Australian regulator, the Australian Pesticides and Veterinary Medicines Authority (APVMA). These treatments should allow effective control, with less off-target impacts and under more situations than currently registered. At least five different mode-of-action herbicides were effective on galenia enabling herbicide group rotation, a strategy that will delay the onset of herbicide resistance.
- Volume 28 Issue 1 - Long-term light trap data from Tasmania, Australia
This article details a trap network that was operated by the Tasmanian state agricultural agency, currently known as the Department of Primary Industries, Parks, Water and Environment (DPIPWE), for several decades. It was established to forecast outbreaks of Persectania ewingii (Westwood), southern armyworm, but many other species were also enumerated. While the armyworm forecasts are outlined elsewhere (Hill 2013), this article summarises the datasets available from the trap network that may be of use to researchers for various purposes.
- Volume 28 Issue 3 - Genetic variation in 'Solanum elaeagnifolium' in Australia using SSR markers
Zhu, Xiaocheng; Wu, Hanwen; Raman, Harsh; Lemerle, Deirdre; Stanton, Rex; Burrows, Geoffrey E
Silverleaf nightshade (Solanum elaeagnifolium Cav.) is a problematic summergrowing perennial weed in Australia. The genetic diversity of silverleaf nightshade is poorly understood. Nine silverleaf nightshade specific and 10 cross-species simple sequence repeat (SSR) primer pairs were utilised to investigate the genetic variations among 94 silverleaf nightshade populations collected in Australia. High genetic diversity was found within silverleaf nightshade populations, with an average genetic similarity of 0.43. The Unweighted Pair Group Method with Arithmetic mean based dendrogram indicated the presence of genetically diverse silverleaf nightshade populations in Australia. However, no well supported genetic structure was found. The Mantel test indicated that there is no significant correlation between genetic variation and geographic distance. These results suggested a lack of geographic structure in genetic diversity, which is probably due to the long distance spread of seeds of silverleaf nightshade. The high genetic diversity of silverleaf nightshade could contribute to the inconsistency in control efficacy between populations.
- Volume 28 Issue 3 - Weeds down under: Invasion of the sub-Antarctic wilderness of Macquarie Island
Williams, Laura; Kristiansen, Paul; Shaw, Justin; Sindel, Brian; Wilson, Susan C
The sub-Antarctic islands are some of the least inhabited and most protected ecosystems in the world. Due to their isolation and low human visitation they have escaped the worst effects of alien plant invasion. The sub-Antarctic islands are all nature reserves due to their high conservation values, and Australia's Macquarie and Heard Islands are World Heritage Areas. The sub-Antarctic climate is harsh and the vascular flora is relatively species poor, yet they support a number of endemic species. Despite the isolation of these islands, 108 alien plant species have become established since European discovery, posing threats to their biodiversity. Poa annua (L.) has quickly become widespread throughout the sub-Antarctic since its introduction and is present on all the major island groups. It is widespread on Macquarie Island, readily colonising disturbed areas and competes with native vegetation for space. The highly invasive capabilities of the grass are due to its high phenotypic and genotypic variability, wide tolerance of environmental conditions, and high fecundity. We are investigating the ecology and control of P. annua to broaden understanding of invasion biology and to assist in the development of non-native plant management in the sub-Antarctic and Antarctic region. While previous studies have shown P. annua is a successful weed, in this study we will quantify its traits and growth in the sub- Antarctic. This paper provides a background to the study of P. annua in the sub-Antarctic.
- Volume 28 Issue 3 - Benefits of national weed initiatives for New South Wales: Successes and future opportunities
Cherry, Hillary; Sheehan, Matt
Effective weed management is most successfully achieved when done in an integrated and coordinated manner. This applies to on-ground action, i.e. implementing weed control, as well as to policy, planning and resourcing. The partnerships and relationships that underpin weed management are equally as important as the 'on-ground' activities. Like weeds, these foundational partnerships should know no boundaries. To achieve landscape-scale outcomes for the protection of biodiversity and production assets, it is critical to integrate local, regional, state and national partners in planning and implementation. This paper demonstrates how national initiatives and the high level plans, strategies and frameworks that result from them, have resulted in stronger partnerships and improved on-ground weed management. We use examples from the last 10 years of the Weeds of National Significance (WoNS) initiative to outline the benefits of collaborative weed management in New South Wales. We then explore how local, regional and state partners in New South Wales can benefit from participation in future national weed management initiatives, including national surveillance, weed spread prevention and WoNS opportunities.
- Volume 28 Issue 3 - Border security: Spotlight on weeds
Cuthbert, Katrina L
Australia formally adopted the Pheloung Weed Risk Assessment (WRA) system to screen new plant introductions in 1997, following the 1996 'Nairn' Review of Quarantine (Nairn et al. 1996). Since the adoption of the WRA system, roughly 3000 plants have been assessed with 47% accepted for importation into Australia, 24% prohibited due to their high weed risk and 29% requiring further evaluation. Despite the large number of WRAs resulting in an 'accept' result, attempts are still being made to illegally import seeds and live plant material. Millions of people, mail parcels, baggage, ships, animals, plants and cargo containers entering Australia are inspected for prohibited articles by the Australian Government Department of Agriculture, Fisheries and Forestry (DAFF) staff every year. In 2012 alone, roughly 26 000 consignments of seeds and 7 100 items of live plant material were seized. The main route of entry was through international airports in passenger baggage. The most commonly seized seeds and live plants were garden ornamentals. Indonesia was the most common country of origin for seized seeds, whilst India was the most common country of origin for seized live plant material. As quarantine risk material is not evenly distributed with arriving passengers and goods, DAFF is implementing reforms to Australia's biosecurity system to better manage the risks of pests entering, establishing and spreading in Australia by targeting areas of highest risk.
- Volume 28 Issue 3 - Containment as a strategic option for managing plant invasion
Grice, AC; Clarkson, John D; Murphy, Helen T; Fletcher, Cameron S; Westcott, David A
Containment is a strategic option that is frequently advocated for dealing with invasive plants. It is often presented as the fall-back option when eradication is deemed unfeasible, notably when eradication attempts are abandoned. However, containment confronts the same needs for detection, delimitation and destruction of plants as eradication. Its main advantage is that the area to be managed is smaller. Its main disadvantage is that the time over which management is required is infinitely longer, assuming that eradication is successful and the containment effort is not abandoned. We argue that a containment program should be built around clearly defined containment units, consisting of an occupied zone and a surrounding buffer zone, at a scale that aligns with the plant's dispersal capacity. There will always be a probability >0 that some propagules will be dispersed beyond any practical buffer zone designed to cover the seed shadow of plants occupying the containment unit. This requires that, under a containment strategy, some resources should be invested in both the occupied zone, to reduce propagule pressure, and the area beyond the buffer zone to deal with the consequences of longdistance dispersal events. Containment is not always easier than eradication or the most cost effective alternative to it.
- Volume 28 Issue 2 - A successful model for community-driven research: The Hieracium Control Trust in New Zealand
Syrett, Pauline; Smith, Lindsay; Scott, David; Aspinall, Sue
The Hieracium Control Trust (HCT) was established in 1992 by a group of farmers keen to promote the development of a biological control programme for Pilosella and Hieracium spp. (hawkweeds), with support from Landcare Research and AgResearch. Over 15 years, the HCT raised over NZ$2 million to fund the survey, screening and introduction of one pathogen and five insect control agents. Releases were made at over 260 sites and control agents have been recovered from over 150 sites. Although agents released have been slow to impact on hawkweed populations, recent data from the North Island indicated that hawkweed gall midges were responsible for a 26% reduction in hawkweed cover. The HCT also leveraged about NZ$500 000 from the Foundation for Research, Science and Technology (FRST), which was used to fund complementary work to assess the significance of existing phytophagous species feeding on hawkweeds and to conduct a simulation study of successful biological control. The hawkweed biological control programme generated in excess of eight refereed papers, 8 conference papers, two PhD theses and 20 reports. Direct funding came from more than 30 organizations, as well as individual farmer contributions. This model, established by the HCT, was adopted by other programmes, both in New Zealand (for broom and Californian thistle) and overseas (for hawkweeds in Idaho and Montana).
- Volume 28 Issue 2 - Identification of, and further evidence for the indigenous status of two weedy bladder ketmia species ('Hibiscus trionum' complex, Malvaceae); and the search for Australia's inland sea
Johnson, Stephen B; Craven, Lyn A
The species known as Hibiscus trionum L. is extremely variable and is best described as a species complex. A recent taxonomic revision of Australasian members of the complex suggested three indigenous species occur. This includes the two troublesome summer cropping weeds, H. verdcourtii Craven, wide or broad leaf bladder ketmia, (previously H. trionum var. vesicarius (Cav.), Hochr.) and H. tridactylites Lindl., narrow leaf bladder ketmia, (previously H. trionum var. trionum). This paper presents information to improve the identification and management of these species. Importantly, after examining early European accounts of the area, the paper presents further evidence that both species are indigenous, contributing information that will aid a world-wide taxonomic revision of the complex. These same accounts resulted in an unexpected conclusion about the search for the "inland sea", the focus of some early European exploration in eastern Australia. While these explorers failed to find this sea, and correctly concluded it did not exist as a permanent entity, they probably did so on erroneous evidence. Large volumes of shallow, slow moving water still inundate the plains surrounding the Barwon, Macquarie and Darling rivers during flooding and these occurrences form one of the likely explanations for such stories.
- Volume 28 Issue 2 - Weeders need more powerful advocates
Responding to the weed crisis needs more than research and action on the ground. Like other major environmental advances, the institutional, legal and policy changes, and resources needed to effectively respond to weed threats require coordinated advocacy. In these days of government shrinkage and budget slashing, weed management reform needs strong community voices more than ever. But it is not a 'hot button' community issue spurring street marches and petitions. Weed practitioners, including in government and academia, have been at the vanguard of driving change in the past, and are essential to advocacy efforts today. The Invasive Species Council challenges the view that those in government or academia should remain narrow in their role and refrain from involvement in advocacy - they too are part of the community and have in-depth knowledge of the need for reform. We appeal for weed practitioners in all domains to consider how they can best support advocacy efforts for weed reforms.
- Volume 28 Issue 2 - Biological control of bridal creeper in southern Victoria: research to community action
Lefoe, Greg; Stephenson, Matthew
An important biological control for bridal creeper, Asparagus asparagoides (L.) Druce, in Australia is the rust fungus Puccinia myrsiphylli (Thuem.) Wint. The rust fungus is now widely dispersed on bridal creeper infestations in southern Victoria. Establishment and dispersal of rust was aided by community adoption of a novel release technique. The success of the program is largely due to partnerships between researchers, land managers and community networks, such as the Bass Coast and South Gippsland Landcare Networks. These partnerships, and the provision of timely information and resources, help to: (i) facilitate the release, establishment and assessment of biological control agents; (ii) ensure biological control is integrated with local and regional weed management strategies; and (iii) promote biological control in the community.
- Volume 28 Issue 2 - Minimising invasive plant spread using the nursery industry national plant labelling guidelines
Kachenko, Anthony G
The Australian nursery industry supplies plants to a wide range of sectors including garden centres, hardware stores, landscaping contractors and for revegetation. To engage all sectors in an effort to encourage voluntary removal of high-risk invasive species from cultivation and sale, the Nursery and Garden Industry Australia (NGIA) have developed voluntary National Plant Labelling Guidelines. The Guidelines were developed in 2007 and updated in early 2013 following extensive consultation across the nursery industry supply chain. This paper provides a detailed insight into the development of these Guidelines and acceptance of them by sectors of the nursery industry supply chain. The benefits of this approach are also discussed for those who adopt the Guidelines. These include good public relations and 'environmentally friendly' branding for those involved, meeting biosecurity commitments and the education and awareness of the wider industry.
- Volume 28 Issue 2 - Proposed new invasive species management legislation for Victoria
de Milliano, Jan-Willem
The Department of Environment and Primary Industries is developing new Invasive Species Management legislation to replace the noxious weeds and pest animal provisions of the Victoria Catchment and Land Protection Act 1994 (CaLP Act) and close the gaps in powers to deal with incursions of taxonomic groups currently not, or only partially, covered by Victoria's biosecurity legislation.
- Volume 28 Issue 2 - Aquatic weeds in Victoria: Where and why are they a problem, and how are they being controlled?
Dugdale, Tony M; Hunt, Trevor D; Clements, Daniel
Aquatic plants are integral components of freshwater ecosystems and provide a number of ecosystem services by providing habitat for fish and aquatic invertebrates, facilitating nutrient cycling and maintaining water quality, and erosion control. However, when in excess, aquatic plants can harm a system by degrading water quality, slowing water velocity, exacerbating siltation or flooding, and reducing species diversity (Madsen 2005). In addition, invasive aquatic weed species which form dense infestations can reduce the diversity of aquatic flora, which can have secondary impacts on aquatic invertebrates and fauna, and fish (van Oosterhout 2009). Such impacts pose a serious threat to the long-term function of freshwater aquatic ecosystems and, if left unchecked, may result in significant habitat alteration (Barnett and Veitch 2007, Yarrow et al. 2009).
- Volume 28 Issue 2 - What the world of weeds can learn from molecular plant breeding
Forster, JW; Cogan, NOI; McLaren, D
What is molecular plant breeding? Molecular plant breeding is a general term for a series of technologies and strategies that are used to improve crop plant species. This includes not only 'genomic' methods, which exploit information on the whole DNA content of plant species, but also other aspects of the so-called 'systems biology continuum', leading to final expression of a particular agronomic trait or character. As a hypothetical example of events occurring across this continuum, it would be possible to imagine a change in the DNA sequence of a gene leading to increased production of the messenger RNA which is the primary product of gene expression, producing higher activity of a protein enzyme that is translated from the RNA, generating higher levels of a key metabolite produced by the enzyme (such a plant alkaloid compound), that is critical for a key physiological process that underpins an adaptive trait (such a toxicity to herbivorous animals). The whole process is critically dependent on capacity in bioinformatics (the science of biological information management), because of the scale of the datasets that are generated. The key objectives of molecular plant breeding projects are typically to enhance crop yield and product quality; to improved tolerance to biotic stresses (pathogens, pests, plant competitors) and abiotic stresses (drought, salinity etc.); and to improve environmental sustainability.
- Volume 28 Issue 2 - Seminar summary
With the title "Many ways to manage a weed" the Weed Society of Victoria was happy to present a range of approaches to weed management. From the traditional methods of herbicide application to newer but well-established biological control and the emerging awareness of the role of genetics in weed management, we covered it all. There was a review of the successes of co-ordinated control strategies under the Weeds of National Significance (WoNS) program an update on how weed legislation will be changing and a call-toarms for the weeds community to lobby for effective change in support of more weed research.