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RNA virus discoveries in the electric ant, Wasmannia auropunctata
Get PDFDespite being one of the most destructive invasive species of ants, only two natural enemies are known currently for Wasmannia auropunctata, commonly known as the electric ant or little fire ant. Because viruses can be effective biological control agents against many insect pests, including ants, a metagenomics/next-generation sequencing approach was used to facilitate discovery of virus sequences from the transcriptomes of W. auropunctata. Five new and complete positive sense, single-stranded RNA virus genomes, and one new negative sense, single-stranded RNA virus genome were identified, sequenced, and characterized from W. auropunctata collected in Argentina by this approach, including a dicistrovirus (Electric ant dicistrovirus), two polycipiviruses (Electric ant polycipivirus 1; Electric ant polycipivirus 2), a solinvivirus (Electric ant solinvivirus), a divergent genome with similarity to an unclassified group in the Picornavirales (Electric ant virus 1), and a rhabdovirus (Electric ant rhabdovirus). An additional virus genome was detected that is likely Solenopsis invicta virus 10 (MH727527). The virus genome sequences were absent from the transcriptomes of W. auropunctata collected in the USA (Hawaii and Florida). Additional limited field surveys corroborated the absence of these viruses in regions where the electric ant is invasive (the USA and Australia). The replicative genome strand of four of the viruses (Electric ant polycipivirus 2, Electric ant solinvivirus, Electric ant virus 1, and Solenopsis invicta virus 10 (in the electric ant) was detected in Argentinean-collected W. auropunctata indicating that the ant is a host for these viruses. These are the first virus discoveries to be made from W. auropunctata
Tailoring ‘Goldfinger’ for improved market prospects
No full textGlobally, there is an increased focus on reducing environmentally harmful anthropogenic activities. More people are becoming conscious about their consumption habits and opting to purchase produce grown in less environmentally-taxing cropping systems (such as organic or agroecological). Likewise, governments and regulatory bodies are restricting and deregistering chemicals which are unmanageably hazardous. The limited genetic diversity of Cavendish bananas, coupled with large-scale monoculture plantations, provides a production system that is particularly susceptible to pest and disease incursions which require significant amounts of chemicals to control. The production of organic bananas would be greatly facilitated if the cultivar grown had genetic resistance to the major disease threats, such as Sigatoka leaf diseases and Fusarium wilt. Organic bananas grown for export only represents about 1% of total production area, however, the launch of the black Sigatoka resistant ‘Pointe d’Or’ cultivar by Carrefour in 2020 was marketed as a revolution in the organic banana trade. This new cultivar has resistance to black Sigatoka while offering consumers an alternative fruit choice. ‘Goldfinger’ is another such alternative to the Cavendish dominated market. Its Fusarium wilt and black Sigatoka resistance makes it a good fit for an organic production system, however, previous attempts to commercialise it in Australia have been unsuccessful, with consumers not favouring its softer pulp and sometimes lacklustre flavour. Mutagenesis, which has been used to breed many widely consumed plant varieties, can greatly assist with creating variants relatively quickly in the search for improved characteristics. Research conducted by the Queensland Department of Agriculture and Fisheries has identified a handful of better tasting ‘Goldfinger’ selections created through a mutagenesis breeding trial. These new cultivars may offer a commercially viable alternative to growers in Fusarium wilt affected regions and integrate well into an organic production system, appealing to the steadily growing market of environmentally conscious consumers. © 2023 International Society for Horticultural Science. All rights reserved
Fire frequency has a contrasting effect on vegetation and topsoil in subcoastal heathland, woodland and forest ecosystems, south‐east Queensland, Australia
No full textEcosystems managed with contrasting fire regimes provide insight into the responses of vegetation and soil. Heathland, woodland and forest ecosystems along a gradient of resource availability were burnt over four decades in approximately 3- or 5-year intervals or were unburnt for 45–47 years (heathland, woodland), or experienced infrequent wildfires (forest: 14 years since the last fire). We hypothesized that, relative to unburnt or infrequent fires, frequent burning would favour herbaceous species over woody species and resprouting over obligate seeder species, and reduce understorey vegetation height, and topsoil carbon and nitrogen content. Our hypothesis was partially supported in that herbaceous plant density was higher in frequently burnt vegetation; however, woody plant density was also higher in frequently burnt areas relative to unburnt/infrequently burnt areas, across all ecosystems. In heathland, omission of frequent fire resulted in the dominance of fern Gleichenia dicarpa and subsequent competitive exclusion of understorey species and lower species diversity. As hypothesized, frequent burning in woodland and forest increased the density of facultative resprouters and significantly reduced soil organic carbon levels relative to unburnt sites. Our findings confirm that regular burning conserves understorey diversity and maintains an understorey of lower statured herbaceous plants, although demonstrates the potential trade-off of frequent burning with lower topsoil carbon levels in the woodland and forest. Some ecosystem specific responses to varied fire frequencies were observed, reflecting differences in species composition and fire response traits between ecosystems. Overall, unburnt vegetation resulted in the dominance of some species over others and the different vegetation types were able to withstand relatively high-frequency fire without the loss of biodiversity, mainly due to high environmental productivity and short juvenile periods
Genetic dissection of root architecture in Ethiopian sorghum landraces
Get PDFThis study quantified genetic variation in root system architecture (root number, angle, length and dry mass) within a diversity panel of 1771 Ethiopian sorghum landraces and identified 22 genomic regions associated with the root variations
Multimethod approach to advance provenance determination of fish in stocked systems
No full textFish stocking occurs in aquatic systems for conservation purposes, to create or enhance recreational fisheries and to enhance wild-catch commercial fisheries. Identifying and quantifying the contribution of stocking efforts to wild populations is crucial to informing these management objectives. Provenance determination methods trade off accuracy, replicability, and cost-effectiveness at fishery-relevant scales. We present and assess multiple methods for provenance determination using a case study of barramundi (Lates calcarifer) in the Dry Tropics region of northern Australia. A novel application of near-infrared spectroscopy (NIRS) is compared to two established methods for fish provenance, otolith microchemistry and genetic parentage analysis using microsatellites. The otolith microchemistry method was able to provide extremely high provenance resolution (>99% accuracy). The microsatellite parentage analysis method had a slightly lower overall accuracy (95%), likely as a result of genetic introgression in this region. Provenance determination using otolith NIRS had the lowest overall accuracy (76%). Once limitations regarding spectral noise, image resolution, and sample size are addressed, NIRS may have potential for cost-effectively determining provenance in fish
Queensland AgTech Roadmap 2023–2028
Get PDFThe Queensland AgTech Roadmap 2023–2028 sets our vision and path to accelerate AgTech innovation and adoption in Queensland. By strengthening collaboration across the AgTech ecosystem and adopting, adapting and advancing technological innovations, Queensland will become a destination for the development and export of world-leading AgTech
East Coast Otter Trawl Fishery Ecological Risk Assessment Species of Conservation Concern
Get PDFThe Queensland Ecological Risk Assessment Guideline (the Guideline) was released in March 2018 as part of the Queensland Sustainable Fisheries Strategy 2017–2027. This Guideline provides an overview of strategy being employed to develop Ecological Risk Assessments (ERAs) for Queensland’s fisheries. The Guideline describes a four-stage framework consisting of a Scoping Study; a Level 1, whole of fishery qualitative assessment; a Level 2, species-specific semi-quantitative or low-data quantitative assessment and; a Level 3 quantitative assessment (if applicable).
A Scoping Study for the East Coast Otter Trawl Fishery (ECOTF) was released in 2023 (Department of Agriculture and Fisheries, 2023). Three comprehensive regional ERAs on the risk posed to trawl bycatch species negated the need to complete a Level 1 for this fishery, therefore the ECOTF was escalated to a species-specific (Level 2 equivalent) assessment. The ECOTF Species of Conservation Concern (SOCC) ERA focused on the species level with risk evaluations based on a Productivity & Susceptibility Analysis (PSA). The PSA evaluates risk for each species through an assessment of seven biological attributes and five fisheries-specific and conservation-related attributes.
Based on the outputs of three existing ERAs (Pears et al., 2012; Jacobsen et al., 2015; Campbell et al., 2017) and following a process by which species with conservation concerns were prioritised for inclusion (including selected species within the Threatened, Endangered and Protected Animals logbook), the ECOTF SOCC ERA assessed the risk posed to 62 species. This included six marine turtles, nine syngnathids, 13 sea snakes, 22 batoids and 12 sharks. Of the 62 species, three were assigned high-risk ratings. The remaining 59 species were assigned precautionary high (n = 9), medium (n = 28), precautionary medium (n = 15) and low (n = 7) risk ratings). The risk profiles for many SOCC were heavily influenced by biological constraints, uncertainty driven by data deficiencies and management limitations.
The ECOTF SOCC ERA made a list of recommendations to assist in the management and mitigation of risk in the ECOTF. A number of these measures are already being discussed and considered as part of the Queensland Sustainable Fisheries Strategy 2017–2027 and the Data validation Plan, and will be progressed through the Trawl Fishery Working Group
Future-proofing extensive livestock production in subtropical grasslands and savannas
No full textPredicted impacts of climate change will negatively affect extensive livestock production in subtropical grasslands and savannas unless proactive strategies are developed to mitigate negative impacts. Livestock adaptation, via breeding for future environments, is key to ensuring livestock health and performance from animals adapted to extensive grazing in hot and unpredictable environments. Grassland and savanna grazing management to ensure an adequate supply of the highest-quality wet season forage (quality) and adequate volumes of dry season forage (quantity) is critically important for extensive livestock production under adverse conditions. Breeding (small adapted animals) and feeding (wet season quality and dry season quantity) are key strategies for future-proofing livestock production in extensive conditions
Litter management to support chicken meat production and industry growth
Get PDFThis project addressed a number of RD&E objectives relating to litter, litter management, litter re-use, odour emissions, litter tilling and in-shed air quality (ammonia and carbon dioxide). Many of these topics are inter-related and it was therefore logical to group these objectives together so they may be addressed holistically.
Project activities included undertaking industry consultation, on-farm measurements/experiments, data collection, literature reviews, and producing fact sheets and case studies relating to litter management practices (such as tilling) and litter re-use. The development of fact sheets and case studies on a range of management practices will form a knowledge foundation, supporting industry to continue to provide the best possible environmental conditions in poultry sheds
An accurate finite element model to study the progressive collapse of post-and-beam mass timber buildings
No full textThe structural behaviour of mass timber buildings under the removal of a load bearing element is complex. To well understand this phenomenon and ultimately develop scientifically based design guidelines against progressive collapse for this type of buildings, there is a need to develop Finite Element models which accurately capture the nonlinear structural responses of such buildings. This paper presents how mass timber post-and-beam systems can be accurately modelled using Finite Element under edge and corner column removal scenarios. The model was validated against published 3D experimental tests performed on scaled-down substructures. Results show that the model accurately replicated non-linear behaviour, load redistribution mechanisms, ultimate loads, failure modes, and strain developments. The use of the model was then illustrated by running parametric studies to quantify (i) the influence of the Cross Laminated Timber (CLT) floor panels layout and (ii) one alternative load path, typically ignored in design, on the progressive collapse resistance capacity