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Fungal communities associated with myrtle rust infection and the use of mycoparasite(s) as potential biocontrol agents against the disease
No full textMyrtle rust, caused by Austropuccinia psidii (formerly Puccinia psidii), is a significant invasive fungal pathogen that poses a serious threat to plants in the Myrtaceae family worldwide. Of the approximately 6,000 myrtle species globally, over 480 have been identified as susceptible, with the host range expanding due to the emergence of a highly virulent biotype. Since the detection of the pandemic biotype in New Zealand, this pathogen has rapidly spread, endangering iconic and ecologically significant myrtaceous flora. First reported in New Zealand in 2017, myrtle rust now affects over 19 native and 17 exotic Myrtaceae species. This study investigates fungal communities associated with myrtle rust infection and identifies potential mycoparasites for use as biocontrol agents. Symptomatic and asymptomatic leaves of native plants, ramarama (Lophomyrtus bullata) and pōhutukawa (Metrosideros excelsa), were collected from four regions across New Zealand (Taranaki, Rotorua, Auckland, and Christchurch). Metabarcoding was used to characterize the fungal microbiome. The results revealed a greater relative abundance of fungal taxa in asymptomatic leaves compared to symptomatic ones. Dominant genera in asymptomatic samples included Colletotrichum, Ilyonectria, Janinaea, Neopestalotiopsis. Pseudozyma, Ramularia, Simplicillium, Vishniacozyma and Zealoasperisporium. In contrast, symptomatic leaves were dominated by Ganoderma, Lophiotrema, Neosetophoma, Pucciniales and Septobasidium. A total of 205 fungal isolates (148 epiphytes and 57 endophytes) were recovered and identified, representing 64 genera. Of these, 18 putative mycoparasites from 9 genera (Alternaria, Cladosporium, Clonostachys, Epicoccum, Myrothecium, Paraconiothyrium, Phlebiopsis, Trichoderma and Sclerostagonospora) were selected for antagonistic activity screening against A. psidii. Three in vitro bioassays were conducted: a detached branchlet assay, spore germination test, and pathogenicity test. Two promising isolates from the genera Cladosporium and Trichoderma were identified, showing 33 -35% colonization of rust pustules two weeks after application and inhibiting 63 - 70% of rust uredospore germination, respectively. These isolates were considered as not pathogenic towards ramarama and pohutukawa with no disease symptoms developing on the inoculated leaves. These selected isolates were further tested under greenhouse conditions with three treatment approaches: putative mycoparasites alone, preventive application (two days before rust inoculation), and curative application (seven days after rust inoculation). Preventive treatments significantly reduced disease severity compared to curative applications. Metabarcoding analysis revealed that Trichoderma and Cladosporium persisted on leaves, comprising 4%, 2%, and less than 1% of the fungal community at 3, 9, and 21 days post-inoculation, respectively. Additionally, the Trichoderma isolate promoted plant regeneration, significantly increasing new shoot growth compared to Cladosporium and the control five weeks after treatment. The interactions between putative mycoparasites Cladosporium, Trichoderma and A. psidii were examined through scanning electron microscopy. These findings contribute to understanding the role of microbial communities in myrtle rust infection and inform the development of biocontrol strategies
Navigating the complexity of Generative artificial intelligence in higher education: A systematic literature review
No full textTechnological innovation has transformed educational settings, enabling artificial intelligence (AI)-driven teaching and learning processes. While AI is still in its embryonic stage in education, generative artificial intelligence has evolved rapidly, significantly shifting the teaching and learning context. With no clarity about the impacts of generative artificial intelligence on education, there is a need to synthesise research findings to demystify generative artificial intelligence and address concerns regarding its application in the teaching and learning process. This paper systematically synthesises studies on generative artificial intelligence in teaching and learning to understand key arguments and stakeholders’ perceptions of generative artificial intelligence in teaching and learning. The systematic review reveals five main domains of research within the field: (i) current awareness (understanding) of generative artificial intelligence, (ii) stakeholder perceptions, (iii) mechanisms for adopting generative artificial intelligence, (iv) issues and challenges of implementing generative artificial intelligence, and (v) contributions of generative artificial intelligence to student performance. This review examines the practical and policy implications of generative artificial intelligence, providing recommendations to address the concerns and challenges associated with generative artificial intelligence-driven teaching and learning processe
Events and wellbeing research: Key arguments, gaps and future directions
No full textThis note reviews the wellbeing research published in Event Management since 2000. It starts by discussing what is meant by wellbeing, then presents an analysis of themes and trends centred around questions of whose wellbeing, what wellbeing, and how to approach wellbeing. Interest in the topic has increased in the last five years. A range of theoretical approaches and methodologies have been adopted, demonstrating interdisciplinarity. In recent times, conceptual frameworks have been developed within event studies as the subject matures. However, studies have centred on the subjective wellbeing benefits of events in an individual, white, Western, non-disabled context, with sports events dominating. There is a need for research that investigates: non-Western understandings and perspectives, including those of Indigenous peoples; the wellbeing benefits of events for a wider range of stakeholders; a broader range of both event and wellbeing types; and longitudinal studies on the longevity of wellbeing benefits
Effectiveness of blood flow restriction training during a taper phase in basketball players
No full textThis study investigates the effectiveness of blood flow restriction (BFR) training in maintaining athletic performance during a taper phase in basketball players. The taper phase aims to reduce external load while maintaining training intensity. Seventeen experienced basketball players were randomised into two groups: a placebo group (n = 8, 22.0 ± 2.1 years, mean ± SD) and BFR group (n = 9, 21.1 ± 1.5 years). The training schedule included strength trainings, team trainings, individual skill sessions and competitive games. During the 4-week taper period, lifting volume was reduced while either maintaining (placebo) or reducing (BFR) lifting load. The BFR group lifted with 60% arterial occlusion pressure at 25–30% of their 1RM, whereas the placebo group trained at 80% of their 1RM with BFR cuffs inflated to only 20%. Compared to the placebo group, BFR participants improved 5 m (−1.4 ± 1.5% mean ± 95% CI p = 0.03) and 10 m (−1.1 ± 0.5%, p = <0.01) sprint performance along with barbell back squat (9.6 ± 8.0%, p = 0.013) and counter-movement jump (1.1 ± 0.8%, p = 0.0035). BFR during the taper phase enabled a reduction in lifting load with no reduction in subsequent performance measures
Disastrous futures? Confronting the scale, urgency andcomplexity of our crises: Introduction to the special issue
No full textWhen then-Climate Change Commissioner James Renwick first saw footage of Auckland's Anniversary Weekend floods (2023), he mistook the images for Bangladesh. ‘“Oh it's Auckland?!” My mouth fell open. I just haven't seen those sorts of images in this country before’ he told a New Zealand Geographic journalist (quoted in Woulfe Citation2023). Worse soon followed. Cyclone Gabrielle hit parts of the country shortly afterwards. Gabrielle has been called ‘an unprecedented weather event’ (McAnulty quoted in McClure Citation2023), the country's ‘largest climate event to date’ (Asia Insurance Review Citation2023). Early indications are that it will be as expensive as the Canterbury Earthquake Sequence (Guinto Citation2023), which, at the time, ‘was the second costliest insurance event of 2010 and the third costliest earthquake in history’ (Bevere et al. Citation2011, p. 6). Arguably these events are but preludes to our disaster-laden future
Natural disasters, unnatural earnings: how do climate disasters impact earnings management?
No full textThis study examines whether managers engage in earnings management to manipulate earnings following climate disasters and how they choose different types of earnings management to achieve earnings targets. Using a large sample of climate disasters from 1989 to 2018 obtained from the Spatial Hazards Events and Losses Database for the United States (SHELDUS), we find that managers tend to exhibit opportunistic behaviors by using earnings management to increase earnings after climate disasters. Furthermore, we find that managers prefer using accrual-based earnings management and classification shifting over real earnings management to achieve earnings goals more quickly. Moreover, we document evidence that the relationship between earnings management and climate disasters can be influenced by other factors such as firm size, frequency of climate disasters, and local institutional environment. Specifically, we find that earnings management employed by managers after climate disasters are more prevalent in smaller companies, companies located in states with a lower frequency of climate disasters, and in states with higher corruption levels
Forestry reform proposals won't address slash emergency
No full textPine forestry is an important economic industry in regional New Zealand. It contributes approximately $6 billion to the national economy annually, and employs about 42,000 people.
However, its large-scale clear-cut harvesting and earthworks practices on steep erosion-prone hill country have contributed to catastrophic downstream damage after cyclones and atmospheric rivers in Gisborne, Hawke’s Bay, Coromandel, Marlborough, Nelson, and Tasman since 2010.
The coalition Government aims to restore public confidence in the industry with its recently announced package of resource management reforms.
However, its policy initiatives for changing the national forestry standards will likely do the reverse
Quantification of key aromatic compounds in plant-based yoghurt alternatives and dairy yoghurts produced using different starter cultures and citric acid and threonine supplements
No full textKey aroma compounds in a large set of coconut- and soy-based yoghurt alternatives and dairy yoghurts representing a broad spectrum of aromas, flavours and their intensities were quantified using head-space solid-phase microextraction (HS-SPME) coupled with gas chromatography mass-spectroscopy (GCMS), 4-methyl-2-pentanol as an internal standard, and the method of external calibration. The importance of matrix matching of external calibration standards to samples by appropriate preparation using the same or similar milk base as well as a pH adjustment was demonstrated. Spike recovery measurements indicated satisfactory measurement accuracy. Moreover, measured concentrations were generally comparable in magnitude to those presented in the literature for similar products. Matrix matching was shown to be less critical for measurement accuracy when deuterated analogues of the aroma compounds are used as internal standards. Finally, addition of citric acid and threonine supplements before fermentation increased aromatic compound production by some starter cultures. This is a novel approach to enhancing the aromas and flavours of plant-based yoghurt alternatives or masking their off-flavours
From root to shoot: morphological evaluation of an international collection of red clover (Trifolium pratense L.) populations
No full textRed clover (Trifolium pratense L.) globally is an important pastoral species, used to strengthen pasture mixes and to produce highly nutritious forage. To ensure its continued use and effectiveness, new adaptable cultivars must be developed. Breeders have continuously harnessed diversity to improve the genetic potential of species, and a key part of this is the introduction of new wild germplasm. This material brings an assortment of genetic variation for key morphological traits for crop improvement and adaptation. A row-column experimental design was used to observe trait responses of 15 red clover populations, including 12 germplasm populations, across 3 years. Thirteen above- and below-ground traits were used to evaluate plant yield, plant persistence and root structure. As expected, the biomass production of most of the 12 wild germplasm populations was low in comparison with the cultivar controls. However, key relationships between root structure and both plant persistence and plant production were identified, with plants having either an expansive or compact root system or a mixture of both. This study explored wild germplasm material and highlights the potential genetic variation available within germplasm collections. As this is one of a few publications that look at both below- and above-ground traits, it also highlights the benefits of finding the right balance between root systems. This includes the need to breed plants that are able to manoeuvre between root systems depending on the growing conditions
A conceptual model for dissolved P mobilization from legacy sources
No full textExcessive phosphorus (P) concentrations can lead to conditions that limit the amenity of freshwater resources. This problem is particularly acute in agricultural catchments, where P fertilizer and manure amendments have been used to increase soil fertility and productivity. In these catchments, P indices are often used to help target critical source areas in order to reduce P exports. However, the overall impact of agricultural mitigation efforts on receiving waters has not always been consistent with declines in total P exports from catchments. In this paper we propose a model of dissolved P mobilization (i.e., entrainment) in surface runoff that accounts for this outcome and examine modifications to P indices that better accommodate dissolved P mobilization. We suggest that dissolved P mobilization commences near the soil surface and has two phases. When water is first applied, labile P is mostly mobilized by dissolution and advection. Subsequently, as the supply of readily accessible P is exhausted, diffusion and hydrodynamic dispersion mobilize P from other sources at a near constant rate for the remainder of the event. As most P exports occur in larger (i.e., longer) events, the second phase appears responsible for most dissolved P exports. Such a model of dissolved P mobilization is consistent with runoff monitoring data under natural and simulated rainfall, suggesting that on low (shallow) slopes where the interaction between surface soil and water may be prolonged, dissolved P concentrations are likely to be higher. Dissolved P mobilization from low-slope areas is not well represented in P indices at present. We suggest that there needs to be a more complex, mechanistic structure to P indices that involves additional compartmentalization. Further, we suggest that this can be achieved without losing the simplicity of P indices or flexibility to integrate research data and experiential knowledge into tools that are relevant to specific regions