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Soil solarisation delivers near zero levels of Fusarium pseudograminearum in cereal crown rot reference sites
Get PDFThe development of commercial varieties that are resistant or tolerant to crown rot caused by Fusarium species is an important goal for cereal breeding programs internationally. Ideally, this research requires experimental sites that are initially free from Fusarium in order to establish treatment plots that compare growth in the presence and absence of these soil- and stubble-borne pathogens. Specifically, the assessment of tolerance requires control plots free of disease to determine the reduction in crop yield in plots where the disease is present. The ability of soil solarisation to reduce the background Fusarium pseudograminearum level occurring at experimental sites in comparison to current stubble management techniques was investigated across three field trials at Wellcamp in Queensland. Stubble from a susceptible durum (Triticum turgidum ssp. durum) cultivar inoculated with F. pseudograminearum was incorporated by cultivation into the trial sites to establish a significant background level of inoculum prior to the application of all subsequent treatment plots. In these trials, solarisation over a period of twelve weeks reduced the presence of F. pseudograminearum to low detection levels when compared to the traditional crown rot management techniques of cultivation or growth of the non-host cover crops mungbean (Vigna radiata) and soybean (Glycine max). No negative effects of solarisation were observed on a subsequent crop of bread wheat (Triticum aestivum), with significantly higher yields observed in the solarised treatments. Solarisation has the potential to deliver near zero level crown rot reference sites for experimental purposes in one short application between cropping seasons
The Effects of Planting Density, Training System and Cultivar on Vegetative Growth and Fruit Production in Young Mango (Mangifera indica L.) Trees
Get PDFIncreasing the planting density of mango orchards appears promising for obtaining higher yields, particularly during the first productive years. However, the challenge is to maintain a good balance between vegetative growth and fruit production in the longer term. The objective of this study was to decipher the effects of planting density, training system and cultivar on young mango trees’ growth and production. The experiment, conducted in North Queensland, consisted of five combinations of planting density and training system applied to the cultivars Keitt, Calypso and NMBP-1243. The planting densities were low (208 tree ha−1), medium (416 tree ha−1) and high (1250 tree ha−1). The closed vase conventional training system was applied at each density. Single leader and espalier on trellis training systems were applied at medium and high densities, respectively. The tree canopy dimensions were measured every 6 months from planting, and tree production was recorded from the third to the fifth years after planting. Vegetative growth and fruit production were the results of complex interactions between planting density, training system, cultivar and/or time. The expected increase in orchard yield with higher planting density was observed from the first productive year, despite lower individual tree production at high planting density. Lower vegetative growth and fruit production at high planting density were probably caused by competition between trees. NMBP-1243 and Keitt showed more rapid vegetative growth. Keitt was the most productive cultivar during the first three productive years. The detailed results of this study provide avenues to further explore the behaviour of mango trees at high planting densities
High water use efficiency due to maintenance of photosynthetic capacity in sorghum under water stress
Get PDFEnvironmental change requires more crop production per water use to meet the rising global food demands. However, improving crop intrinsic water use efficiency (iWUE) usually comes at the expense of carbon assimilation. Sorghum is a key crop in many vulnerable agricultural systems with higher tolerance to water stress (WS) than most widely planted crops. To investigate physiological controls on iWUE and its inheritance in sorghum we screened 89 genotypes selected based on inherited haplotypes from an elite or five exotics lines, containing a mix of geographical origins and dry vs. milder climates, which included different aquaporin (AQP) alleles. We found significant variation among key highly heritable gas exchange and hydraulic traits, with some being significantly affected by variation in haplotypes among parental lines. Plants with a higher proportion of the non-stomatal component of iWUE still maintained iWUE under WS by maintaining photosynthetic capacity, independently of reduction in leaf hydraulic conductance. Haplotypes associated with two AQPs (SbPIP1.1 and SbTIP3.2) influenced iWUE and related traits. These findings expand the range of traits that bridge the trade-off between iWUE and productivity in C4 crops, and provide possible genetic regions that can be targeted for breeding
Storage Effects on the Physicochemical Properties, Phytochemical Composition, and Sugars in Red-Fleshed Cultivars, ‘Rubycot’ Plumcot, and ‘Queen Garnet’ Plum
Get PDFDomestic storage conditions can have a significant impact on the composition of phytochemicals and sugars in stone fruits. This study aimed to evaluate the effect of two domestic storage temperatures (4 and 23 °C) on the physicochemical properties, phytochemical composition, and sugars of ‘Rubycot’ (RC) plumcot, a novel stone fruit variety, and ‘Queen Garnet’ (QG) plum. Initially, RC had a lower total anthocyanin concentration (TAC) than QG, but TAC in RC increased significantly (p < 0.05) during storage, peaking at +95% after 7 days at 23 °C, while QG reached +60% after 14 days. At 4 °C, TAC increased for both varieties (RC +30%, QG +27%). RC had a higher initial total phenolic content (TPC), which also increased for both fruits. QG had a significantly higher initial total quercetin concentration (TQC), increasing by 40% (p < 0.05) at 23 °C. The initial total carotenoid concentration in QG was higher than that in RC, but after 10 days at 23 °C, RC had a higher carotenoid concentration than QG. Both varieties showed similar sugar profiles, with QG starting higher but decreasing over time at both storage temperatures. Results from this study showed that ambient storage significantly increases total anthocyanins, total quercetins, and TPC in RC and QG. However, it is important to evaluate the textural and sensory properties of stored RC and QG in terms of consumer acceptability of the stored fruits
The tidyomics ecosystem: Enhancing omic data analyses
Get PDFThe growth of omic data presents evolving challenges in data manipulation, analysis, and integration. Addressing these challenges, Bioconductor1 provides an extensive community-driven biological data analysis platform. Meanwhile, tidy R programming2 offers a revolutionary standard for data organisation and manipulation. Here, we present the tidyomics software ecosystem, bridging Bioconductor to the tidy R paradigm. This ecosystem aims to streamline omic analysis, ease learning, and encourage cross-disciplinary collaborations. We demonstrate the effectiveness of tidyomics by analysing 7.5 million peripheral blood mononuclear cells from the Human Cell Atlas3, spanning six data frameworks and ten analysis tools.Competing Interest StatementR.G. has received consulting income from Takeda and Sanofi, and declares ownership in Ozette Technologies. M.K. is an employee of and declares ownership in Achilles Therapeutics. The remaining authors declare no competing interests
Genetic matching and the identification of a promising biocontrol agent validates a decision to survey natural enemies of Urena lobata in Malaysia
Get PDFUrena lobata is a major introduced pasture weed in Vanuatu where a biocontrol program to mitigate its impacts commenced in 2018. There was considerable uncertainty regarding the native range of U. lobata, although published literature, coupled with very simple climate matching suggested that Southeast Asia should be the most promising region in which to survey for natural enemies. We, therefore, conducted surveys for candidate biocontrol agents in Malaysia and conducted genetic matching to compare plants growing in Vanuatu, Malaysia, and other regions in the invaded and purportedly native range of U. lobata. Surveys in Malaysia prioritized a tingid bug Haedus vicarius as a promising candidate agent for the biocontrol of U. lobata and subsequent host specificity testing confirmed it is sufficiently host specific to be released in Vanuatu. Genetic matching indicated that plants growing in Malaysia are a good match to plants present in Vanuatu, validating our selection of survey sites
Integrating the L (learning) into PAR (participatory action research)
Get PDFDeclining soil organic matter, soil health and loss of natural fertility are major constraints to sustainability on Australian grain farms. Improved knowledge of soil health is required by those managing Australian soils - farmers. An extension program was delivered to Queensland grain growers in 2022/23 to develop participants' knowledge and their capacity to improve soil management. This program utilised Participatory Learning and Action Research, which combined a structured action learning approach that established on-farm participatory action research to start improving soil health. During the program over 70 properties self- assessed their soil health utilising their own soil data. Growers then identified their top priorities and new management practices they wanted to test in their paddocks. Deep placement of phosphorus was the highest rated priority and the management practice growers most wanted to test in their paddocks (49%). On-farm research sites were implemented to test and refine these practices on participants' properties
Association of soil bacterial diversity and composition with Fusarium wilt disease of bananas in Yogyakarta Province, Indonesia
Get PDFInfection of banana plants with Fusarium oxysporum f. sp. cubense Tropical Race 4 (Foc-TR4) leads to a cascade of changes in the rhizosphere, resulting in changes to the soil physicochemical properties and bacterial community composition. This study aimed to determine the core taxa associated with different soil physicochemical properties and disease statuses and to identify the factors exerting the greatest influence on the soil bacterial community composition of bananas in Special Region of Yogyakarta Province, Indonesia. Rhizospheric soil from healthy and infected plants was collected from four banana locations, including Kulon Progo, Gunungkidul, Bantul, and Sleman districts, at 10-30 cm depth between May and September 2021. Laboratory analysis was conducted for soil physicochemical properties, and the abundance of Foc-TR4 was undertaken. Additionally, 16S rRNA gene-based metagenomics analysis was used to quantify bacterial diversity in all samples. Soil type significantly influenced the abundance and composition of the bacterial community more than disease status did. Contrarily, disease status groups influenced the complexity of bacterial network interaction more than soil type. Actinobacteriota, Proteobacteria, Chloroflexi, Acidobacteriota, and Bacteriodota are the major phyla associated with all soils. This study identified 60 bacterial genera as core members of the banana rhizosphere. These core bacterial genera include various plant growth-promoting bacteria involved in nitrogen fixation, phytohormone production, siderophore production, and biocontrol mechanisms for producing antifungal compounds. Our work provides a basis for future research on the soil bacterial composition associated with banana plants to enhance plant health against Fusarium wilt disease. © 2024, Society for Indonesian Biodiversity. All rights reserved
Stock assessment of Queensland east coast burrowing blackfish (Actinopyga spinea), with data to June 2023
Get PDFBurrowing blackfish are species of sea cucumber from the family Holothuriidae that is found in northeastern Australia, New Caledonia, and possibly other Melanesian countries. In Australia, burrowing blackfish distributions extend along the entire Great Barrier Reef (GBR). They often occur in shallow to deeper depths from 1–25 m.
This is the first stock assessment conducted on Queensland east coast burrowing blackfish by Fisheries Queensland. This stock assessment considered burrowing blackfish as three distinct populations, one associated with Gould Reef (Gould), one associated with the Capricorn Bunker Group (Bunker), and one associated with Lizard Island (Lizard). No stock assessment result is provided for Lizard.
All assessment inputs and outputs are referenced on a financial year basis (that is, ‘2023’ means July 2022–June 2023).
This assessment used a one-sex age-structured population model and a delay-difference model which led to similar results. The outputs of the age-structured model are presented as the main results for all three species in this assessment.
The assessment incorporated commercial catch and effort data spanning 1995 to 2023 as well as length composition data and estimates of absolute abundance from recent surveys undertaken in 2023. No recreational or Indigenous catch data were available and catches from these sectors are considered negligible. There are no discards due to the highly selective nature of the fishery.
Several Stock Synthesis scenarios were run to examine the implications of different fixed model parameters such as steepness (h) and natural mortality (M) on model outcomes. All scenarios were optimised using Markov chain Monte Carlo (MCMC) to better explore the robustness of the models. From these exploratory scenarios a final base case was chosen for each species. The base case Stock Synthesis results indicated that the biomass ratio of Gould at the beginning of 2024 financial year was between 51% and 101% of unfished levels. The base case Stock Synthesis results indicated that the biomass ratio of Bunker at the beginning of 2024 financial year was between 78% and 109% of unfished levels. The Lizard stock assessment modelling process failed to reconcile fishing pressure with the biomass decline observed through survey estimates of absolute biomass
Evaluation of full-sized and thick cross-laminated timber using in-line non-destructive techniques
No full textAdvancements in non-destructive evaluation systems for predicting mechanical properties of cross-laminated timber appear to have been limited to laboratory scale, reduced sample sizes, or difficult practical solutions for industry implementation. This study has developed classical vibration analysis methods for industry adoption in large-scale, rapid panel characterisation through frequency analysis. The non-destructive method allowed for the prediction of the elastic moduli in both axial directions (Ex and Ey) and shear moduli (Gxz, Gyz, and Gxy) for thin or thick plates. The comparison with the static reference method and non-destructive technique showed a good consistency for predicting the elastic and shear moduli of the cross-laminated timber with mean percentage differences for Ex, Ey, and Gxy of 5.2%, 7.9%, and 18.9%, respectively. An observation was made that the accurate determination of the mechanical properties required enough correctly identified frequencies/modes. Mode shapes generated from experimental data through modal assurance criterion were compared with finite element analysis to confirm the assessment method yielded frequencies specific to the panel, rather than other contributing effects (environment, boundary conditions, panel variability, mesh resolution)