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Psocids as Global Pests of Stored Products
No full textPsocids are a group of insect pests of stored products. They are widespread and damaging. This book summarises current knowledge of Psocid biology and management and points the way to future psocid research. The book is essential reading for all those involved in stored product and post-harvest pest management and research
Queensland Low Emissions Agriculture Roadmap 2022–2032
Get PDFThe Queensland Low Emissions Agriculture Roadmap 2022–2032 (the roadmap) provides a strong framework to achieve a low emissions agriculture sector by reducing production-based emissions and increasing carbon farming. Its strength is its co-design with key industry partners and government.
The roadmap is intended to be a living document, evolving with the needs and ambitions of its partners. The roadmap’s preferred futures and actions will be reviewed and refreshed mid-term to reflect the new technologies and market drivers influencing outcomes across the agribusiness supply chains. This roadmap focuses on sector transition, partnering with industry to build the foundations for material action on greenhouse gas (GHG) emissions reduction.
Different industries in the agriculture sector are at different stages of developing and implementing GHG emissions reduction targets. This roadmap has been designed to support industries to deliver against their targets and work towards the Queensland Government commitment of a zero net emissions economy by 2050
Impacts of Myrtle Rust Induced Tree Mortality on Species and Functional Richness within Seedling Communities of a Wet Sclerophyll Forest in Eastern Australia
Get PDFAustropuccinia psidii is an introduced plant pathogen known to have caused significant declines in populations of several Australian native Myrtaceae species. However, limited research has focused on the impacts of the pathogen on plant communities in the aftermath of its invasion. This study investigated the relationship between disease impact level, plant species diversity, and functional richness in seedling communities in a wet sclerophyll forest in southeast Queensland. A clear shift was found from early colonizer Myrtaceae species in the mid- and understory to a more diverse non-Myrtaceae seedling community indicative of secondary succession. Comparisons of key Myrtaceae species and the seedling community suggest that there may also be a shift towards species that produce drupes and larger seeds, and overall, a current reduction in fruit availability due to the dramatic loss of previously dominant species. Seedling diversity showed no significant correlation with tree mortality, possibly due to favorable rainfall conditions during the study period. The more subtle changes in forest composition, such as changes in fruit type and availability due to myrtle rust, however, could affect the visitation of local bird species in the short term and certainly reduce the store of early colonizing native shrub and tree species
Growing Degree Day Targets for Fruit Development of Australian Mango Cultivars
Get PDFA forward estimate of mango (Mangifera indica L.) harvest timing is required for farm management (e.g., for organization of harvest labour and marketing). This forward estimate can be based on accumulated growing degree days (GDD) from an early stage of flowering to fruit harvest maturity, with fruit maturity judged on a destructive assessment of flesh colour and dry matter content. The current study was undertaken to improve GDD targets for Australian mango cultivars, to improve estimation of harvest maturity, and to document a methodology recommended for future work characterizing fruit maturation GDD for other mango cultivars. An alternate algorithm on GDD calculation involving use of a function that penalizes high temperatures as well as low temperatures was demonstrated to better predict harvest maturity in warmer climates. Across multiple locations and seasons, the required heat units (GDD, Tb = 12 °C, TB = 32 °C; where TB is upper base temperature of 32 °C and Tb is lower base temperature of 12 °C) to achieve maturity from asparagus stage of flowering was documented as 2185, 1728, and 1740 for the cultivars Keitt, Calypso and Honey Gold, respectively. GDD difference between the asparagus and two-thirds floral opening stages of flowering was 188 ± 18 for Calypso, 184 ± 12 for Honey Gold, 238 ± 21 for Keitt and 175 ± 10 for KP. Colour specifications for a colour card set suitable for maturity assessment of all cultivars was also proposed. A flesh colour harvest maturity card specification of 9 was proposed for the cultivar Honey Gold and 13 for the cultivar Keitt
Validating moisture-safe energy efficient CLT assemblies in hot and humid climates using experimental testing
Get PDFClimate specific cross-laminated timber (CLT) construction detailing to manage moisture risks in subtropical and tropical regions of Australia is validated through experimental testing, statistical analysis, and computational hygrothermal modelling. Three projects in Australia are monitored: a CLT micro-unit built in a subtropical climate, a small CLT structure assembled inside a controlled double climatic chamber simulating a tropical environment, and an existing residential building located in a tropical climate. Several parameters are altered in the experiment design to understand the most reliable assemblies for CLT buildings in hot and humid climates that can sufficiently control the moisture risks. The findings suggest that the hygrothermal modelling guidance from ASHRAE 160 pertaining to construction unprotected from stormwater accurately represents CLT assemblies in hot and humid climates. The importance of adhering weather resistant membranes (WRB) to both the external face and edge grains of the CLT panels is revealed. In tropical climates, the positioning of internal insulation and WRB with increased vapour resistance are also shown to be beneficial, while ventilated cavities and drainage layers behind the cladding is critical for rain protection
Invasive wild deer exhibit environmental niche shifts in Australia: Where to from here?
Get PDFInvasive species have established populations around the world and, in the process, characteristics of their realized environmental niches have changed. Because of their popularity as a source of game, deer have been introduced to, and become invasive in, many different environments around the world. As such, deer should provide a good model system in which to test environmental niche shifts. Using the current distributions of the six deer species present in Australia, we quantified shifts in their environmental niches that occurred since introduction; we determined the differences in suitable habitat between their international (native and invaded) and their Australian ranges. Given knowledge of their Australian habitat use, we then modeled the present distribution of deer in Australia to assess habitat suitability, in an attempt to predict future deer distributions. We show that the Australian niches of hog (Axis porcinus), fallow (Dama dama), red (Cervus elaphus), rusa (C. timorensis), and sambar deer (C. unicolor), but not chital deer (A. axis), were different to their international ranges. When we quantified the potential range of these six species in Australia, chital, hog, and rusa deer had the largest areas of suitable habitat outside their presently occupied habitat. The other three species had already expanded outside the ranges that we predicted as suitable. Here, we demonstrate that deer have undergone significant environmental niche shifts following introduction into Australia, and these shifts are important for predicting the future spread of these invasive species. It is important to note that current Australian and international environmental niches did not necessarily predict range expansions, thus wildlife managers should treat these analyses as conservative estimates
Study of the hygroscopic properties of three Australian wood species used as solid wood and composite products
Get PDFThe use of engineered wood products and mass timber panels such as cross laminated timber (CLT), glued laminated timber (glulam) and laminated veneer lumber (LVL) is becoming more common, as these products have benefits in terms of environmental credentials and resource utilisation and have the potential to provide faster and more economical construction processes. However, timber exposed to moisture for prolonged periods can degrade biologically, leading to a loss of appearance and decreased mechanical properties. Southern pine, radiata pine and shining gum timber are important forest resources for the Australian timber industry. To date, no in-depth studies on the hygroscopic properties of these species have been carried out from a timber wetting point of view. Consequently, existing literature has a knowledge gap regarding the determination of moisture movement properties in these species that are applicable to numerical modelling when used as solid wood or in the production of engineered wood products (EWPs). The work presented herein will help develop a better understanding of moisture ingress and egress in solid timber and EWPs and provide data for future predictive tools (such as numerical modelling) for moisture management in timber buildings. Samples were prepared from solid timber as well as EWP’s to examine the relationships between glue lines and edge gaps in CLT and multiple glue lines in LVL on moisture movement. As expected, longitudinal permeability was higher than radial and tangential permeability for the species tested. Southern pine samples had higher gas and liquid permeability values than radiata pine and shining gum. CLT with end grain sections including an edge gap had higher gas and liquid permeability than similar sections with glue lines only. LVL sections with 1 glue line had slightly lower permeability values than in samples with 2 glue lines. Gas and liquid permeabilities were lower for LVL samples than a two-layered veneer section without a glue line illustrating the barrier posed by the glue line. The moisture loss parameter during the diffusion testing was higher for LVL ends and CLT ends with edge gaps than face and edge sample sections. The results will be used to develop numerical models for moisture behaviour in solid and composite timber panels when exposed to humidity and free water. It is recommended to conduct additional studies to examine the impact of the adhesive layer and its properties on impeding moisture migration or functioning as a moisture barrier
Haplotype resolved chromosome level genome assembly of Citrus australis reveals disease resistance and other citrus specific genes
Get PDFRecent advances in genome sequencing and assembly techniques have made it possible to achieve chromosome level reference genomes for citrus. Relatively few genomes have been anchored at the chromosome level and/or are haplotype phased, with the available genomes of varying accuracy and completeness. We now report a phased high-quality chromosome level genome assembly for an Australian native citrus species; Citrus australis (round lime) using highly accurate PacBio HiFi long reads, complemented with Hi-C scaffolding. Hifiasm with Hi-C integrated assembly resulted in a 331 Mb genome of C. australis with two haplotypes of nine pseudochromosomes with an N50 of 36.3 Mb and 98.8% genome assembly completeness (BUSCO). Repeat analysis showed that more than 50% of the genome contained interspersed repeats. Among them, LTR elements were the predominant type (21.0%), of which LTR Gypsy (9.8%) and LTR copia (7.7%) elements were the most abundant repeats. A total of 29 464 genes and 32 009 transcripts were identified in the genome. Of these, 28 222 CDS (25 753 genes) had BLAST hits and 21 401 CDS (75.8%) were annotated with at least one GO term. Citrus specific genes for antimicrobial peptides, defense, volatile compounds and acidity regulation were identified. The synteny analysis showed conserved regions between the two haplotypes with some structural variations in Chromosomes 2, 4, 7 and 8. This chromosome scale, and haplotype resolved C. australis genome will facilitate the study of important genes for citrus breeding and will also allow the enhanced definition of the evolutionary relationships between wild and domesticated citrus species
Drought Stress Affects the Reproductive Biology of Avena sterilis ssp. ludoviciana
Get PDFAvena sterilis ssp. ludoviciana (hereafter, A. ludoviciana) is considered the most difficult-to-control winter weed in the Northern Grains Region (NGR) of Australia. The abundance of this weed has increased after the adoption of the no-tillage conservation agriculture (NTCA) approach, which does not bury seeds deep in the soil profile. In addition, the increasing frequency and intensity of drought stress events during the late winter to early spring period in the NGR may modify this weed’s persistence mechanisms, which may further impact crop production. The present study focused on plant maturity time and seed production, dormancy, and longevity of four NGR A. ludoviciana biotypes in relation to the severity of drought stress over 2 consecutive years. Plants of all four A. ludoviciana biotypes were grown under 100% plant available water capacity (PAWC) until panicle initiation. At panicle initiation, very mild (80% PAWC), mild (60% PAWC), moderate (40% PAWC), and severe (20% PAWC) drought stresses were imposed on plants and continued through to maturity; an additional subset of plants were maintained at 100% PAWC through to maturity (control). Plants exposed to severe drought stress matured 24 days earlier than control plants, and produced 34% fewer filled seeds, with seeds having a 42% lower mass, 70% less dormancy, and shorter predicted longevity of at least 2 years compared to the seeds produced on control plants. All reproductive traits were less affected when the severity of the drought stress was decreased. The increasing frequency of drought stress in combination with the widely adopted practice of NTCA favours seeds of A. ludoviciana to undergo rapid germination in the following autumn/winter NGR planting season. However, effective control of A. ludoviciana remains a challenge in the NGR due to this weed’s genetic variability with respect to its response toward the seasonal variability of the NGR
Stock assessment of Queensland east coast endeavour prawns (Metapenaeus endeavouri and Metapenaeus ensis), Australia, with data to December 2021
No full textEndeavour prawns (Metapenaeus endeavouri and Metapenaeus ensis) are endemic to the tropical and subtropical waters of Australia and are widely distributed along the coastline of northern Australia from Shark Bay in Western Australia to the eastern coast of northern New South Wales. The species live approximately two years and have a maximum observed size of 44 mm carapace length for female and 32 mm carapace length for male blue endeavour prawns and 41 mm carapace length for female and 33 mm carapace length for male red endeavour prawns. Sexual maturity is reached at approximately 6 months of age and around 24–26 mm carapace length.
This is the first stock assessment conducted on Queensland east coast endeavour prawns by Fisheries Queensland. Assessment work carried out during a Master’s Thesis did not produce comparable outputs.
This stock assessment includes input data through to December 2021. All assessment inputs and outputs were referenced on a calendar year basis (that is, ‘2021’ means January 2021–December 2021).
The assessment used a one-sex monthly delay-difference population model, fitted to catch rates. An age-structured model was also trialled, however this did not lead to outcomes that were considered plausible by the project team.
The model incorporated data spanning the period 1958 to 2021 including mandatory daily commercial logbook data collected by Fisheries Queensland (1988–2021), historic voluntary logbook data (1970–1988), Queensland Fish Board data (1958–1981), historic catch records (1958–2014), survey and logbook gear data collected by Fisheries Queensland (1988–2021), high resolution vessel tracking data collected by Fisheries Queensland (2000–2021) and lunar data (1958–2021). Length data collected by Fisheries Queensland (1998–2009) were also incorporated in a modelling scenario.
The stock assessment was guided by a project team consisting of scientists, managers, and industry representatives.
Fourteen scenarios were run using a delay-difference model, covering a range of modelling assumptions and sensitivity tests. All scenarios were optimised using Markov chain Monte Carlo (MCMC) to better explore the robustness of the models. Project team preferred scenario results indicated that the endeavour prawn stock experienced a decline from the period 1958 to 1997 to reach 34% of unfished biomass. The biomass has been steadily rising since this time, and in 2021 the stock level was estimated to be 69% of unfished biomass (54–87% range across the 95% credible interval)