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Spray-topping pastures
No full textSpray-topping or pasture topping is the application of a sub-lethal rate of herbicide when grasses are coming into head and flowering.
The aim is to reduce the production of viable seed and the seedling population in the following year. The grass is not killed by the herbicide application.
Spray-topping is normally carried out in preparation for the following season\u27s cropping program
Wild radish and its management in crops
No full textWild radish (Raphanus raphanistrum) is highly competitive in crops and can cause a yield loss of 10 to 90 %.
Wild radish has fibrous stems that make harvesting difficult by choking the header comb, it is an alternative host for numerous pests and diseases, and it can cause animal health problems when grazed
A spatio-temporal modelling approach to understand the effect of urban fruit fly outbreaks on peri-urban orchards
No full textUrban areas are well-known sources of fruit fly introduction and unmanaged populations pose a high risk of dispersal to surrounding agricultural areas. Although management of urban fruit fly populations is recognised as being important for area-wide control programmes, its relative importance is rarely quantified. Identifying possible sources of fruit fly populations is important to the success of area-wide programs, as well as to on-farm management. We developed a modelling approach to analyse the spatio-temporal connectivity of fruit fly across urban-agriculture boundaries. For a case study, we examine Mediterranean fruit fly, Ceratitis capitata, outbreaks in two fruit growing regions in south-west Western Australia. Connectivity between population sources was defined using a dispersal kernel and routinely collected surveillance data from traps located across urban and agricultural areas. Spatio-temporal Bayesian models were then developed to quantify the extent to which unmanaged urban populations contribute to commercial orchards across each region. Our model results from two fruit growing regions indicate that population connectivity is a strong predictor of urban and commercial orchard Mediterranean fruit fly density. Models demonstrate that unmanaged urban outbreaks can contribute to increased pest pressure in surrounding orchards up to 2 km, but the urban contribution quickly declines over this distance. We also demonstrated that our models provide a means of predicting changes in Mediterranean fruit fly density across a region. Regional scale inference from our models may be particularly useful for sites where surveillance trapping data is unavailable. With an increasing risk of fruit fly incursions from expanding urban areas into agricultural regions, it is important to understand the processes driving population connectivity to target pest management strategies. By modelling surveillance trapping data and population connectivity, we can quantify how unmanaged urban pest infestations can contribute to pest pressure in nearby commercial orchards. Such information can help pest managers quantify the risk posed by unmanaged urban infestations when designing and implementing area-wide management
Including methane emissions from agricultural ponds in national greenhouse gas inventories
No full textAgricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the Australian government, in compliance with the Paris Agreement. Total annual methane emissions increased by 58% from 1990 (26 kilotons CH4 year–1) to 2022 (41 kilotons CH4 year–1). This increase is linked to the water surface of agricultural ponds growing by 51% between 1990 (115 kilo hectares; 1,150 km2) and 2022 (173 kilo hectares; 1,730 km2). In Australia, 16,000 new agricultural ponds are built annually, expanding methane-emitting water surfaces by 1,230 ha yearly (12.3 km2 year–1). On average, the methane flux of agricultural ponds in Australia is 0.238 t CH4 ha–1 year–1. These results offer policymakers insights into developing targeted mitigation strategies to curb these specific forms of anthropogenic emissions. For instance, financial incentives, such as carbon or biodiversity credits, can mobilize widespread investments toward reducing greenhouse gas emissions and enhancing the ecological and environmental values of agricultural ponds. Our data and modeling tools are available on a free cloud-based platform for other countries to adopt this approach
Traditional and contemporary measures of recreational fishing activity to inform sustainable management of Blue Swimmer Crab (Portunus armatus) fisheries in Western Australia
No full textRecreational fishing is a popular activity that has many social and economic benefits. Monitoring has traditionally centred around measuring fishing effort and catch. However, contemporary measures, such as fisher demographics and behaviours, which may be linked to social and economic objectives, are now recognised as necessary to meet expectations that all aspects of resource use are considered for fisheries management. The challenge for recreational fisheries is how to regularly provide information across a growing diversity of metrics, and at a scale relevant to specific fisheries, with limited resources. The Blue Swimmer Crab (Portunus armatus) is one of the most commonly recreationally harvested species in Western Australia. This species served as a case study to explore if data from five broad-scale phone-diary surveys between 2011–2012 and 2020–2021 could be adapted to meet expanded information needs. Twelve discrete fisheries represented small spatial-scale areas for fisheries management, with some variation in management arrangements (i.e., bag limits). Robust estimates of traditional and contemporary measures could be produced for three fisheries: Peel-Harvey Estuary, Swan-Canning Estuary and Geographe Bay. Traditional measures of participation, fishing effort, total catch and harvest from 2011–2012 to 2020–2021 were generally consistent for Swan-Canning Estuary but decreased for Peel-Harvey Estuary and Geographe Bay. The proportion of harvest from recreational and commercial fishing varied from mixed use (Swan-Canning Estuary, Peel-Harvey Estuary) to recreational only (Geographe Bay). Variation in contemporary measures was also evident, with recreational fishing largely undertaken by local residents in Swan-Canning Estuary, while participation was more uniform between local and non-local residents in Peel-Harvey Estuary and Geographe Bay. We found that broad-scale surveys could be successfully adapted to meet the growing need for information on contemporary measures to support a holistic approach to sustainable fisheries management for small spatial-scale recreational fisheries
Differences in fisher demographics and fishing behaviour from concurrent phone-recall and smartphone app surveys of recreational angling in south-western Australia
No full textTraditional methods for collecting robust samples of recreational effort and catch data from offsite mail or telephone surveys are becoming increasingly difficult to obtain. Smartphone applications (apps) that allow recreational fishers to report their effort and catch are a potentially viable data collection tool, but may be biased. We evaluated demographics, effort, and catch of freshwater anglers in south-west Western Australia by comparing independent data from concurrent phone-recall and app-diary surveys for a 12-month period in 2017–2018. Survey modes differed, with higher proportions of app respondents angling in freshwater and being avid anglers. For both survey modes, unweighted mean effort (days fished) was higher in dams than rivers, but was higher from the phone-recall survey for dams and rivers. The unweighted distribution of kept and released catches (number of fish per angler) of rainbow trout (Oncorhynchus mykiss) and redfin (Perca fluviatilis) were similar between survey modes, with higher retention of redfin and higher release of rainbow trout. Kept and released rates of freshwater cobbler (Tandanus bostocki) and brown trout (Salmo trutta) were less common in both survey modes. Lower response rates and higher survey participation by avid anglers (≥20 days per year) from the app-diary survey may bias survey data. Such bias needs to be addressed when using digital data collection methods, along with improving recruitment and retention of app participants
Working group on recreational fisheries surveys (WGRFS)
No full textEditors
Estanis Mugerza • Kieran Hyder
Authors
Adam Lejk • Alexander Winkler • Amélie Régimbart • Anastasios Papadopoulos • Anders Kagervall Anna-Marie Winter • Annica de Groote • Antanas Kontautas • Branko Dragicevic • Christian Skov Chun Chen • Chris Bova • Dace Zilniece • David Vertegaal • Diarmuid Ryan • Didzis Ustups Eneko Bachiller • Estanis Mugerza • Evanthia Karasavva • Filipa Duarte • Filipe Freitas Henriques Freya Ivy Palmer • Grace Farrell • Hannah Rudd • Hans Jacob Olesen • Harry Vincent Strehlow Henrik Pärn • Hugo Diogo • Joana Patricio • João Pontes • John Foster • Jules Selles • Karina Ryan Keno Ferter • Kieran Hyder • Krzysztof Radtke • Lara Salvany • Leonardo Venerus • Leonie O\u27Dowd Luca Bolognini • Mafalda Rangel • Marc Simon Weltersbach • Marta Pujol-Baucells • Martín García Asorey • Martín Laporta • Martin Mortensen • Martin Wiech • Martina Scanu • Matthew Farthing Miikka Husa • Mišo Pavesi • Paz Jiménez • Pablo Pita • Paul Venturelli • Pedro Veiga • Pentti Moilanen Qilei Zhao • Sabrina Colella • Samantha Hook • Samira Nuñez • Sean Tracey • Stephen Taylor Thomas Lanssens • Thomas Verleye • Valerio Sbragaglia • Warren Potts • Wendy Edwards Zachary Radford.
Executive summary
The ICES Working Group on Recreational Fisheries Surveys (WGRFS) is tasked with compiling and validating data from European marine recreational fisheries (MRF) to support ICES assessment and advisory processes. In 2024, WGRFS undertook a wide range of activities focused on MRF, including the consolidation and assessment of national survey programs, the validation of novel methodologies, and the provision of guidance regarding data availability, quality, and use. Additional responsibilities included facilitating regional data collection and storage, exploring human dimensions of MRF, and conducting assessments of workshops hosted by the group. These sessions emphasized information exchange, national survey program evaluation, intersessional activities, and strategies for scientific publication. Discussions covered a diverse set of topics, such as the launch and outcomes of new national survey initiatives across various regions, including China, Sweden, Azores, Croatia, and Australia. Updates on MRF were also provided by the European Commission and angling community representatives. Findings from the Regional Coordination Groups were shared, along with approaches to include MRF in assessment and advisory processes. ICES have been tasked with providing advice on MRF, so an ICES roadmap has been developed giving key recommendations. MRF can be important as a food source, so the impact of this for food safety and human health was considered. The core focus of the meeting centred on evaluating progress, developing strategies, and the intersessional groups (ISGs). The ISGs are the primary mechanism for WGRFS activities addressing areas including governance, survey methodology, quality assurance, regional coordination and data storage, catch-and-release practices, animal welfare, stock assessment and reconstruction, novel methods, human dimensions, and communication and engagement. Given the extensive scope of discussions and outcomes, a comprehensive summary is not possible here; however, detailed information is presented in the main text
Pastoral grasses and legumes as potential host plants for fall armyworm Spodoptera frugiperda (J.E. Smith) development
No full textThe fall armyworm, Spodopterafrugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a highly polyphagous, migratory pest native to the tropical and subtropical region of Americas. Grass crops particularly corn have been most heavily impacted since S. frugiperda invaded Australia in 2020. In northern Western Australia, S. frugiperda is primarily a problem in dry season (May to October) crops when there are abundant host plants available in monocultures. During the wet season (November to April) it is not known what host plants may support larval growth and development. Accordingly, this present study undertook a no-choice feeding bioassay to assess larval and pupal development on several grasses and legumes that are present over the wet season in northern Western Australia to evaluate their potential as suitable host plants for S. frugiperda. Maize (control) and sorghum were the most suitable hosts for S. frugiperda development as they supported greater larval and pupal survival, heavier larvae and pupae, and shorter development period. Following maize and sorghum, pastoral grasses, particularly blue grass, and a weedy grass, barnyard grass, had comparable effects on larval and pupal development. Legume pastures (Cavalcade, butterfly pea, and siratro) were unsuitable hosts in this bioassay as very few larvae completed their development to adults. This study demonstrates the potential for rangeland pasture grasses and weedy grasses as wet season host plants for S. frugiperda. They provide the necessary green bridge for S. frugiperda populations to survive. It is recommended that pastoralists monitor their grass forage for S. frugiperda and consider management if significant reductions in biomass are detected
Diversity of Gibberellin 2-oxidase genes in the barley genome offers opportunities for genetic improvement
No full textIntroduction
Gibberellin (GA) is a vital phytohormone in regulating plant growth and development. During the “Green Revolution”, modification of GA-related genes created semi-dwarfing phenotype in cereal crops but adversely affected grain weight. Gibberellin 2-oxidases (GA2oxs) in barley act as key catabolic enzymes in deactivating GA, but their functions are still less known. Objectives
This study investigates the physiological function of two HvGA2oxgenes in barley and identifies novel semi-dwarf alleles with minimum impacts on other agronomic traits. Methods
Virus-induced gene silencing and CRISPR/Cas9 technology were used to manipulate gene expression of HvGA2ox9 and HvGA2ox8ain barley and RNA-seq was conducted to compare the transcriptome between wild type and mutants. Also, field trials in multiple environments were performed to detect the functional haplotypes. Results
There were ten GA2oxs that distinctly expressed in shoot, tiller, inflorescence, grain, embryo and root. Knockdown of HvGA2ox9 did not affect plant height, while ga2ox8a mutants generated by CRISPR/Cas9 increased plant height and significantly altered seed width and weight due to the increased bioactive GA4 level. RNA-seq analysis revealed that genes involved in starch and sucrose metabolism were significantly decreased in the inflorescence of ga2ox8a mutants. Furthermore, haplotype analysis revealed one naturally occurring HvGA2ox8ahaplotype was associated with decreased plant height, early flowering and wider and heavier seed. Conclusion
Our results demonstrate the potential of manipulating GA2ox genes to fine tune GA signalling and biofunctions in desired plant tissues and open a promising avenue for minimising the trade-off effects of Green Revolution semi-dwarfing genes on grain size and weight. The knowledge will promote the development of next generation barley cultivars with better adaptation to a changing climate
Soil amelioration in Western Australian cropping systems: a review of the benefits, adoption, and value
No full textOver the past 17-years soil amelioration approaches have developed to include one-off (strategic) deep soil mixing or inversion tillage in Western Australian (WA) cropping systems. Deep ripping developments include increased ripping depth to 50-80cm, and topsoil inclusion or subsurface delving capability. Strategic deep tillage (i.e. mechanical amelioration) is applicable to ~13 M hectares of WA’s south-west agricultural soil consisting of deep sands, sandy earths, deep sandy duplex and ironstone gravel. Subsoil acidity, subsoil hardpans, topsoil water repellence, sodicity, poor fertility and low water holding capacity often constrain these soils. DPIRD researchers maintain a database of amelioration responses which contains more than 220 site-year inversion and deep mixing comparisons. Cereal grain yield increases range from 0.14-0.91 t/ha for inversion and 0.21-0.73 t/ha for deep mixing across a range of soil types and seasons after amelioration. Narrow-leafed lupin yield responses to deep mixing or inversion range from 0.19-0.54 t/ha and canola from 0.21-0.49 t/ha. Comprehensive grower surveys in 2020 and 2024 showed an increase in from 52 to 66 % of grower respondents undertaking strategic deep tillage, with 51 % ripping, 24 % mixing and 17 % inverting their soils in 2023-24. For growers using mechanical amelioration 97 %, regularly applied lime to manage soil acidity. A DPIRD-commissioned study by consulting firms Planfarm and Farmanco utilised deidentified client financial data to show growers who over the past 10-years had adopted ‘complete’ amelioration packages increased farm operating profit by $100 /ha/year and had 2.6 kg/ha.mm higher wheat water use efficiency than those who hadn’t. Increased value and resilience of WA cropping will come with improved spatial management of refined soil amelioration and profile reengineering practices