12903 research outputs found
Sort by
Unmanned aerial vehicle phenotyping of agronomic and physiological traits in mungbean
No full textMungbean is an important sub-tropical legume crop grown across Asia, Africa, and Australia. Yield improvement is crucial for expanding production, but phenotyping important traits across diverse environments using current approaches is challenging, limiting the scale and complexity of information captured. High-throughput phenotyping platforms offer a solution by rapidly screening traits at scale. This study deploys an unmanned aerial vehicle (UAV) platform to determine the potential of phenotyping a range of agronomic and physiological traits within a diverse mungbean population evaluated across three field trials. Three predictive data-driven modeling approaches were undertaken to evaluate performance accuracy in predicting these traits: linear regression, stepwise regression, and partial least squares regression. Results show that using the geometric trait “coverage” as a proxy is most suitable for screening visual traits like early vigor. For functional traits (i.e., aboveground biomass), predictive data-driven models demonstrate high accuracy during early- and mid-canopy development stages (R2 0.79, root mean square error [RMSE] 4.08 and R2 0.8, RMSE 26.92, respectively), but accuracy declines in late-canopy development (R2 0.33 and RMSE 43.15). Prediction accuracy can be optimized by using different modeling approaches at different stages during the transition from early- to mid-canopy development as well as canopy closure. Similar findings were observed when examining the prediction models for the physiological trait, stomatal conductance (R2 0.69 and RMSE 0.10). These approaches are expected to enable breeders and researchers to incorporate UAV-based phenotyping systems into mungbean improvement programs. Such approaches might be most efficiently used at scale if applied as part of a “real-time” calibration approach
DaMYB75 and DaMYB56 antagonistically regulate anthocyanin biosynthesis by binding to the DaANS promoter in Dioscorea alata
No full textThe yam Dioscorea alata L. is widely cultivated globally. Purple-fleshed varieties of this important crop have enhanced market value due to their high anthocyanin contents, but how anthocyanin biosynthesis in D. alata tubers is regulated remains poorly understood. In this study, we identified and functionally validated key transcription factors that regulate anthocyanin biosynthesis based on a comparative transcriptome and metabolome analysis of three D. alata cultivars with different colored tubers (dark purple, light purple, and white). The anthocyanin glycoside cyanidin-3-O-(2′′-O-glucosyl) glucoside was abundant during early tuber development, and we determined that its accumulation is regulated in opposite manners by two R2R3-MYB transcription factors: DaMYB75 and DaMYB56. Yeast two-hybrid and bimolecular fluorescence complementation assays in Nicotiana benthamiana and co-expression assays in D. alata demonstrated that DaMYB75 promotes anthocyanin biosynthesis by specifically activating the promoter of the late anthocyanin biosynthesis gene DaANS and enhancing its expression through an interaction with DabHLH72. By contrast, DaMYB56 is a negative regulator of anthocyanin biosynthesis that binds to the DaANS promoter together with DabHLH72. Furthermore, the methylation levels of the DaMYB75 promoter were significantly lower in purple tubers than in white tubers. These findings shed light on the regulation of anthocyanin biosynthesis by MYBs and provide the basis for genetically improving anthocyanin content in D. alata
Plant biosecurity and One Health: government and industry roles as risk creators and mitigators
No full textThe One Health concept highlights the interconnectedness of human, animal, and environmental health and places significant importance on plant biosecurity. This is due to the profound impact of plant biosecurity on food safety and security for animals and people, biodiversity, and the economy. This narrative review examines the roles of government and industry as risk creators and mitigators in plant biosecurity within a One Health framework, focusing on how their collaboration can strengthen surveillance, enhance regulatory policies, and mitigate the spread of plant pests and diseases. Plant biosecurity, which encompasses the measures to safeguard plant biosecurity and life in the same way that animal biosecurity safeguards animal and human health and life, is a critical component of One Health. Measures include a range of policies, regulations, strategies and activities to protect plants from exotic and established pests and diseases. Government, industry, and community actions are critical elements of plant biosecurity. These include pest surveillance and the establishment and maintenance of pest-free areas. Government agencies and industry professionals play a central and pivotal role in shaping plant biosecurity by implementing policies and regulations and developing innovative strategies. These actions can have a dual effect on plant biosecurity: they can either mitigate risks by preventing the introduction and spread of pests or create risks if regulations are inadequate or poorly enforced. The success of plant biosecurity efforts depends on how well government policies align with One Health principles, which require a careful balance between economic, environmental, social and health-related technical/scientific considerations. Pest surveillance, a foundational element of plant biosecurity, provides the tools for early detection and rapid response to pest outbreaks, essential for protecting plant biosecurity. Surveillance programs enable continuous monitoring of pest populations and the detection of emerging threats, which is critical for maintaining pest-free areas. The benefits of pest surveillance are numerous and extend beyond plant biosecurity, contributing to broader One Health objectives by reducing the risk of zoonotic diseases and preserving the ecological integrity of ecosystems. It underpins important economic and trade objectives by projecting confidence in the safety and health of Australia’s agricultural products to international trading partners. Strategies to achieve and maintain pest-free areas include stringent quarantine measures, continuous surveillance, and effective rapid response protocols. The interconnectedness of plant biosecurity with One Health is evident in these efforts, as maintaining pest-free areas supports ecosystem health, minimises the need for chemical interventions and consequent pressure on antimicrobial resistance, and promotes sustainable agricultural practices. Government actions, pest surveillance, and the maintenance of pest-free regions are essential components of a robust plant biosecurity strategy. By aligning these measures with One Health principles, it is possible to protect plant biosecurity, enhance environmental sustainability, and contribute to global health outcomes. This holistic approach highlights the importance of cross-sector collaboration and the need for solid biosecurity frameworks to safeguard plant biosecurity in an increasingly interconnected world
Altered calcium and potassium distribution maps in tomato tissues cultivated under salinity: studies using X-ray fluorescence (XFM) microscopy
No full textCalcium (Ca2+) distribution into relatively low-transpiring fruit versus relatively high-transpiring leaves is of concern to the fruit industry. Ca2+ uptake is further compromised under salinity through antagonistic competition with sodium (Na+). Herein, X-Ray Fluorescence (XFM) was applied to elucidate in-situ localization and distribution patterns of Ca2+ and potassium (K+) in tomato leaflet and fruit tissues under salinity versus non-saline controls. Leaflet Ca2+ signal was up to 7 times higher than that in fruit. Highest Ca2+ hotspots were in leaflet blades, notably at their margins. XFM spatial maps revealed striking contrasts in K+ versus Ca2+ patterns along proximal–distal mesocarp tissues. Under compressive stress, proximal fruit flesh tissues were firmer, stiffer and showed higher resilience to mechanical deformation than distal tissues. This intrinsic mechanical gradient property was positively correlated with Ca2+ locality. Added Ca2+ ameliorated mechanical failure induced by Na+ and restored fruit firmness, but not stiffness and peak force. The exocarp had the strongest Ca2+ signal in fruit tissue. The weakest was in the locular cavity. Ca2+ in Blossom End Rot (BER) affected tissue was up to fourfold that in immediately surrounding sound tissue, reflecting cell wall collapse. New insights reported here into Ca2+ and K+ dynamics in tomato mesocarp under salinity offer improved understanding of fruit mechanical properties and Ca2+-deficiency
Overexpression of Leptochloa fusca H+-pyrophosphatase (LfVP1) gene improves salinity and drought tolerance in tobacco
No full textPhysiologically, salinity causes osmotic stress due to high solute concentration in soil and disturbs the metabolic and photosynthetic activity of the cells by increasing the toxicity of Na+ in the cytoplasm. Plant adaptation to salt stress is characterized by cellular ion homeostasis and vacuolar sequestration of toxic ions from cytosol mediated by H+-pyrophosphatase (H+-PPase). The LfVP1 gene was cloned under the control of the Gal1 promoter for yeast transformation and the CaMV35S promoter for tobacco transformation. Yeast supplementation assay demonstrated that ena1 and ena1:nhx1 yeast mutants, transformed with LfVP1 genes, could only be able to partially complement the effect of NaCl and hygromycin in the presence of a functional Na+/H+ antiporter gene. Transgenic tobacco plants transformed with the LfVP1gene had significantly higher photosynthetic levels, stomatal conductivity, relative water content, membrane stability index, and negative osmotic potential under osmotic stress compared to wild-type plants (WT). Seeds of the transgenic line LfVP1-PB4 (single gene insertion) and WT were germinated on the MS0 medium supplemented with 200 and 250 mM NaCl. Transgenic plants showed better growth and tolerance to salinity stress than WT plants. Our findings indicate that the overexpressing LfVP1 gene has a potential role in enhancing the abiotic stress tolerance in crops such as rice, wheat, and maize
Tailoring agrichemical release kinetics through material design: Understanding the counterintuitive effect of matrix hydrophobicity
No full textNitrification inhibitors (NIs), such as dicyandiamide (DCD), can improve the nitrogen uptake efficiency by plants and reduce environmental losses. Unfortunately, DCD degrades rapidly through microbial action in tropical conditions, limiting its efficacy. Here, the encapsulation and controlled release of DCD as a model water-soluble, crystalline agrichemical was studied within biodegradable matrices comprising blends of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL). DCD was mixed at 40 wt% and extruded with PHBV:PCL blends at polymer mass ratios of 1:0, 3:1, 1:1, 1:3 and 0:1 to produce ∼3 × 3 mm cylindrical pellets. The release kinetics into water were monitored over 12 weeks at 10, 23 and 40 °C. A Fickian diffusion model fitted the data well and the diffusivities followed an Arrhenius dependence on temperature. Counterintuitively, the more hydrophobic PHBV matrix released DCD the fastest. Release kinetics slowed as the PCL content increased, except for the neat PCL matrix. The lower affinity between the hydrophobic PHBV and hydrophilic DCD led to the DCD being relatively excluded from the PHBV phase and hence more accessible to interconnected voids and channels. In contrast, the higher affinity between PCL and DCD led to PCL-coated DCD crystals, which reduced direct water access to the DCD. Therefore, as the content of PCL was increased, the layer of PCL through which water and dissolved DCD must diffuse also increased, slowing release. This work demonstrated the ability to control DCD release from a biopolymer matrix through material design, with complete release taking between a few days to several months depending on the blend ratio
Accounting for population structure in genomic prediction of strawberry sweetness at a global scale
No full textGenomic prediction models that fit multiple environments globally are valuable tools for assessing cultivar performance across diverse and variable growing conditions. We analyzed 2,064 strawberry (Fragaria × ananassa) accessions genotyped with 12,591 SNP markers. Soluble solids content (SSC) was measured in multi-year trials conducted at seven locations spanning the U.S., Europe, and Australia. Population structure analysis grouped accessions into two major clusters corresponding to subtropical and temperate origins, which was confirmed by significant differences in allele frequency distributions. To improve prediction accuracy across environments, we developed factor analytic models focusing on genotype-by-environment interactions rather than covariance between sub-populations. We compared three genomic prediction approaches: (i) a standard GBLUP model (Gfa), (ii) a GBLUP model incorporating principal component analysis eigenvalues and re-parameterization (Pfa), and (iii) a multi-population GBLUP model that fits sub-population genomic relationship matrices (Wfa). The Pfa and Wfa models achieved the highest prediction accuracy (r = 0.8) for SSC, outperforming individual environment models and the standard GBLUP. These findings demonstrate that accounting for population structure and genotype-by-environment interactions enhances multi-environment genomic prediction and supports practical implementation of genomic selection in global strawberry improvement programs
Assessing the Sustainable Economic Benefits of Clonal Tissue Culture in Fruit‐Tree Industries: A Scenario‐Based Avocado Case Study in Australia
No full textThere is an increasing global demand for fruit/nut tree foods. Traditionally, these trees are propagated via grafting onto rootstocks grown from seeds or using the double‐grafting technique, but this is laborious, expensive, and slow to provide seedlings to the industry. Although clonal tissue culturing can improve the supply and quality of seedling rootstock year‐round, little is known if this propagation technique is economically viable at the commercial scale. This study aims to fill this gap by investigating the economic benefits to avocado growers of clonal tissue‐cultured seedling adoption over traditional propagation methods. Queensland is the largest producer of Australian avocados; therefore, we used a bioeconomic model of an indicative Queensland avocado farm under different adoption scenarios. Bio‐physical and economic data were collected from local Queensland farms, nurseries and advisors. Findings revealed that the scenario of supplying fruit trees a year earlier with clonal tissue culture rootstock had greatest financial benefits to growers. For an indicative 25‐ha avocado farm, this included reduced investment costs of A3373/ha/year, and the grower’s wealth increased by more than $840k after 20 years. This increased wealth is from earlier seeding supply, which equates to a similar benefit from increasing crop yields by 10% over the 20‐year time horizon. This research contributes towards science technology adoption, product commercialisation, industry adoption theories, and provides further insights into the sustainable economic benefits of clonal tissue culture to avocado farmers’ resilience through increased gross margins, reduced initial capital investment, shorter payback periods, and thereby reducing the risk typically associated with establishing perennial tree‐crop enterprises. Globally, other fruit/nut tree industries may benefit from clonal tissue culture, not only through possible yield increases, but more importantly through shorter breeding cycles for cultivars to increase the supply of seedlings when required
DNA metabarcoding provides new insight into the diet of invasive chital deer (Axis axis) in a tropical savanna landscape
No full textThe introduction of non-native species into new environments can cause significant ecological harm and is considered a major conservation threat. As populations of invasive species continue to establish and increase across the globe, novel methods can provide new insights into their biology and potentially aid in management. In this study, we examined the diet of non-native chital deer (Axis axis) in a tropical savanna environment in northern Australia. Using DNA metabarcoding of fecal samples, we described the dietary items consumed by 149 individuals over a two-year sampling period and associated each item with individual body condition. The DNA metabarcoding method detected significantly more dietary items consumed by individual chital deer at each of the taxonomic levels (family, genus, and species) when compared with previous analyses. We observed marked differences in diet composition across multiple seasons and sites. Significantly more sequences from the genera Terminalia, Diospyros, Jasminum, and Hakea were detected in samples collected from individuals in poor condition during the dry season, suggesting that a different suite of food resources is being consumed by a subset of individuals during periods when forage quantity and quality is low. Most notably, our results indicated that chital are consuming a browse-dominated diet throughout the year, differing from previous macroscopy analyses which suggested chital are predominantly grazers during the wet season in northern Australia. Our findings give support for the use of DNA metabarcoding to qualitatively assess diet composition compared to macroscopic analysis and suggest that the restricted availability of food during the dry season may result in the consumption of poor quality and detrimental dietary items
Utilising citizen science data for monitoring released biological control agents on invasive weed species
No full textMonitoring is conducted to determine the establishment and spread of an introduced agent, detect any off-target damage and denote the success of a mass rear and release program. If the presence of agents is observed in this time, distribution data is collected, and once long-term establishment is achieved, the rear and release program enters into the field redistribution stage. Monitoring is normally done by people involved within the project, however in recent years the use of citizen science on data collection platforms such as iNaturalist Australia (iNaturalistAU) or Atlas of Living Australia (ALA) has expanded. This has created an opportunity for researchers to utilise released agent detections and spread on a wider scale through citizen science