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Biocontrol of tomato psyllid (Bactericera cockerelli) using individual application of Trichoderma atroviride or Engytatus nicotianae and their combination
No full textThe management of tomato potato psyllid (TPP), Bactericera cockerelli, is problematic because of pesticide resistance and environmental issues. Engytatus nicotianae has shown promising predatory effect on TPP in glasshouses. Trichoderma isolates have been reported to alter the behaviour of pests or their enemies by modifying plant defence metabolites such as volatile organic compounds (VOCs). We investigated the individual and combined efficacy of Trichoderma atroviride and E. nicotianae against TPP abundance and across different developmental stages (eggs, nymphs, adults) and the number of infested leaves in glasshouse grown tomatoes. Plant VOC emissions were also investigated under the different treatments. Across all measured TPP stages the treatments (E. nicotianae alone, T. atroviride alone, and T. atroviride + E. nicotianae) significantly reduced mean TPP counts relative to the control but there were no significant differences in VOC emissions among the treatments. Trichoderma atroviride alone was less effective than E. nicotianae alone or its combination with Trichoderma atroviride to suppress TPP populations. The combined use of T. atroviride + E. nicotianae did not show significant advantages over the use of E. nicotianae alone in supressing TPP suggesting the combined use may need to be assessed for other advantages of Trichoderma to crop including growth promotion or pathogen defence
Protecting and restoring freshwater biodiversity across urban areas in Aotearoa New Zealand—Encouraging the installation of rainwater tanks in urban areas
No full textThis synthesis was prepared by New Zealand’s Biological Heritage National Science Challenge | Ngā Koiora Tuku Iho, Empowering Kaitiakitanga & Environmental Stewardship research team.
Unless New Zealanders are inspired to act and work together for a common goal, the response to our biodiversity crisis will be disjointed, ad-hoc, and potentially counterproductive. Our research focuses on addressing this dilemma. It is about helping New Zealanders take charge of caring for the environment by understanding the values and motivations that drive some people to actively protect our natural heritage. It is also about understanding the reciprocal relationships between people in the landscape – some of whom actively intervene on behalf of the environment – and the ecosystems in which they live
Mapping the vulnerability of groundwater to saltwater intrusion from estuarine rivers under sea level rise
No full textSurface water bodies connected to the ocean such as estuarine rivers can act as pathways for saltwater intrusion (SI, i.e., the displacement of fresh groundwater by saltwater in an aquifer) far inland of the coast, presenting one of the earliest risks associated with relative sea level rise (SLR). However, SI vulnerability mapping approaches have largely focused on SI from the coast and do not consider estuarine surface water bodies, except for GALDIT–SUSI (Kazakis et al., 2019); a weighted indexing approach designed for regional-scale mapping applications using a Geographic Information Systems (GIS) framework. However, GALDIT-SUSI is subjective in ranking the importance of factors that can contribute to SI and combining these into a vulnerability index. A less subjective approach to assessing SI vulnerability than weighted indexing methods involves the use of physically-based analytic solutions such as Strack (1976), but these have not been applied in a GIS framework or along estuaries and rivers previously. Here, these analytic solutions, surface water salinity, and surface water-groundwater freshwater head gradients are used in the development of a new SI vulnerability tier system. This new approach was applied in the low-lying coastal city of Ōtautahi Christchurch, Aotearoa New Zealand, along 70 km of coastal, estuary, and river margins under current sea level and SLR using GIS, then compared to GALDIT–SUSI. The main advantage of the SI vulnerability tiers method is that it considers surface water behaviour, e.g., increased saltwater encroachment up rivers under SLR, which exposed new areas of the aquifer to saltwater and increased SI vulnerability upstream. In contrast, GALDIT-SUSI does not consider surface water conditions and accounts for topography and groundwater level as the main SI vulnerability drivers in this application. The SI vulnerability tiers proposed here are more theoretically robust than GALDIT-SUSI and provide a physically-based, large-scale, relatively low-budget and rapid screening tool to highlight areas most vulnerable to SI under current and future conditions for further monitoring and management; a gap of national and international relevance
Parental financial support for housing: The importance of investment homes and family size
No full textAs global housing affordability declines among young people, parental financial housing support has become a crucial mechanism for the transmission of family housing wealth. This study aims to assess the influence of parental ownership of primary and investment properties on the mechanism of providing housing support to their offspring. Using data from a representative survey of the New Zealand population, our study reveals that parental ownership of investment properties plays a predominant role in their ability to provide housing support to their children, whereas the ownership of primary residences does not affect this support. Interestingly, we find that that this effect remains significant even after controlling for parental household income and savings. This suggests that the impact of investment properties on housing support is not solely attributed to their contribution to income or savings. Furthermore, our findings indicate that parental ownership of investment properties has a more pronounced impact on providing substantial housing support. Additionally, wealth inequality in housing transmission appears to be more prominent in households with multi-child. As the effect of parental housing are significant in multi-child families, an effect not observed in one-child households. These findings reveal the inequality in the transmission of housing wealth through the mechanism of parental housing support
Establishing a comprehensive web-based analysis platform for Nicotiana benthamiana genome and transcriptome
No full textNicotiana benthamiana has long served as a crucial plant material extensively used in plant physiology research, particularly in the field of plant pathology, because of its high susceptibility to plant viruses. Additionally, it serves as a production platform to test vaccines and other valuable substances. Among its approximately 3.1 Gb genome, 57 583 genes have been annotated within a 61 Mb region. We created a comprehensive and easy-to-use platform to use transcriptomes for modern annotation. These tools allow to visualize gene expression profiles, draw molecular evolutionary phylogenetic trees of gene families, perform functional enrichment analyses, and facilitate output downloads. To demonstrate their utility, we analyzed the gene expression profiles of enzymes within the nicotine biosynthesis pathway, a secondary metabolic pathway characteristic of the Nicotiana genus. Using the developed tool, expression profiles of the nicotine biosynthesis pathway genes were generated. The expression patterns of eight gene groups in the pathway were strongly expressed in the roots and weakly expressed in leaves and flowers of N. benthamiana. The results were consistent with the established gene expression profiles in Nicotiana tabacum and provided insights into gene family composition and expression trends. The compilation of this database tool can facilitate genetic analysis of N. benthamiana in the future
Harder, better, faster, stronger? Dispersal in the Anthropocene
No full textThe dispersal of organisms in the Anthropocene has been profoundly altered by human activities, with far-reaching consequences for humans, biodiversity, and ecosystems. Managing such dispersal effectively is critical to achieve the 2030 targets of the Kunming–Montreal Global Biodiversity Framework. Here, we bring together insights from invasion science, movement ecology, and conservation biology, and extend a widely used classification framework for the introduction pathways of alien species to encompass other forms of dispersal. We develop a simple, global scheme for classifying the movement of organisms into the types of dispersal that characterise the Anthropocene. The scheme can be used to improve our understanding of dispersal, provide policy relevant advice, inform conservation and biosecurity actions, and enable monitoring and reporting towards conservation targets
Biological control of the soilborne pathogen Rhizoctonia solani in Asian cabbage : a thesis submitted in partial fulfilment of the requirements for the Degree of Master of Horticultural Science at Lincoln University
No full textBrassicas are common vegetable crop in most parts of the world, including Papua New Guinea (PNG). However, pathogens can affect vegetable brassica production. Rhizoctonia solani is a serious fungal soil-borne pathogen that causes damping off and bottom rot of emerged seedlings. It attacks the hypocotyl or lower stem tissue of the plant and causes wire stem. In severe infections the stem separates from the root and dies. Asian cabbage (Pak Choi) is widely grown in PNG, but the effects of R. solani on its production, or methods for control to the pathogen are not known. This research programme investigated the efficacy of biological control methods to manage R. solani in Asian cabbage. Two New Zealand strains of R. solani (043-1 and 043-4) were evaluated for their virulence on Asian cabbage, with strain 043-4 being identified as more virulent and used in subsequent experiments. Four Trichoderma isolates (T. atroviride LU132, T. hamatum LU785, T. harzianum LU1347, and T. polysporum LU1358) from the Lincoln University culture collection were formulated into a seed coating and tested for their biocontrol potential in comparison with that of the seed treatment fungicide Apron XL using soil naturally infested with R. solani. T. hamatum LU785 significantly improved seedling emergence and survival, while T. atroviride LU132 enhanced plant growth parameters in a study. A further trial compared the effectiveness of T. hamatum LU785 and a ground mustard (Brassica juncea) biofumigation applied as seed treatments. Both treatments increased seedling emergence in the presence of the pathogen and increased early plant growth.
Additionally, the biofumigation properties of glucosinolates from Brassicaceae species were assessed in the glasshouse. The incorporation of Frozen cauliflower tissues into the growing medium provided better control of the pathogen and allowed greater plant growth than fresh or frozen tissues of other brassica species.
This study has identified the potential for using Trichoderma spp. and biofumigation to reduce the impact of R. solani on the production of Asian cabbage, but these results require confirmation in field studies
Unveiling undisturbed alpine lake ecosystems: A multiproxy approach to reconstruct past ecological response to climate variability in the New Zealand Southern Alps
No full textApart from natural variations in environmental and climatic conditions, human activities (e.g. land-use changes) can have major impacts on freshwater ecosystems. In the context of New Zealand, the arrival of humans approximately 750 years ago has left a permanent mark on landscapes, posing challenges in discerning undisturbed natural conditions for paleoclimatic reconstructions. Yet, remote alpine lakes in the Southwest Pacific can serve as pristine archives of environmental and climate changes, hardly influenced by human activities.This study focuses on sediment cores obtained from two neighbouring catchments of Lake Bright and Lake Laffy in Fiordland National Park, situated in an understudied remote area of New Zealand’s Southern Alps. Employing a multiproxy approach, we utilized bulk C and N stable isotopes, lipid biomarker analysis, and high-resolution X-ray fluorescence and hyperspectral imaging to reconstruct Holocene changes in catchment dynamics and climate. Here, we present a new precipitation record based on the compound-specific composition of hydrogen isotopes of plant wax n-alkanes as well as a branched glycerol dialkyl glycerol tetraethers (brGDGTs) derived temperature reconstruction. Examining a sequence spanning the late Holocene, we discern events of evolving environmental conditions impacting these catchments.Our biomarker paleorecord from Lake Bright revealed a relatively stable temperature range during the last 4 ka, indicating that the changes in the sedimentary record might be dominantly shaped by the local hydroclimate. The low compound δ2H values observed reflect precipitation that has been orographically uplifted over the Southern Alps. Downcore δ2H variations are likely influenced by changes in the isotopic composition of rainfall driven by regional temperature and latitudinal sources of westerly precipitation. In this context, we present these episodes of hydroclimatic variability and derive the ecosystem response to prevalent conditions by correlating the respective changes in lake productivity, water quality and shifts in vegetation composition.Finally, we extend this record through the Holocene to the last local glacial termination about 10 ka ago using the Lake Laffy stratigraphy and engage in a discussion regarding the potential implications of enhanced climate variability on the future integrity of New Zealand's pristine alpine ecosystems
The nexus between livelihood goals and livelihood strategy selection: Evidence from rural China
Get PDFThis study explores the nexus between livelihood goals (LGs) and livelihood strategy (LS) selection preferences. We construct a measurement of three livelihood goals (survival, security, and self-respect goals) by combining qualitative and quantitative analysis and classify livelihood strategies into three groups (agricultural, non-agricultural, and diversification) based on household income sources. The multinomial logit model with fixed effects empirically estimates the relationship between livelihood goal indices and livelihood strategy selection with panel data (2010–2018) from the China Family Panel Studies surveys (CFPS). The results show that households with survival goals are more likely to choose the agricultural and diversification strategies and less likely to select the non-agricultural strategy. Households with security and self-respect goals are more likely to choose the non-agricultural strategy and are less likely to select the agricultural strategy. Families with a higher self-respect goal level are more flexible in livelihood strategy selection. The livelihood strategy selection preference is consistent in different regions of rural China when households pursue survival and security maximization. From the low-level survival goal to the high-level self-respect goal, consistent with a gradual transition from a low-income agricultural strategy to the high-income non-agricultural strategy; the diversification strategy is the transformed livelihood strategy in this process
CSR agents and mining in New Caledonia: Development brokerage and spatializing effect
No full textNickel extraction and processing have had a profound impact on the social, political, and colonial/decolonial trajectory of New Caledonia over the past 150 years. This activity has not only reshaped the material and mental landscapes of the region, but has also given rise to intermediary agents whose roles and designations have evolved over time. The onset of transnational corporations in the 2000s gave rise to several "travelling models" such as IBA, CSR, and SLO, which act as institutional and material means of conveying global discourses such as sustainable development.
This communication is centred on CSR officers as development brokers, an aspect of CSR anthropological literature that has received relatively little attention. The contribution suggests two hypotheses: firstly, that CSR officers differ from traditional development brokers in that they structurally work for the local embedding of the company, and second, that they have a spatialising effect on the definition of mining impact perimeters and the configuration of the mining arena at the local and New Caledonian levels.
The analysis draws on data from research projects conducted between 2008 and 2022, particularly focusing on the social biographies of key CSR officers who operate across different firms and sectors, have been utilized. By exploring the spatial dimension of CSR brokerage and its link to company strategy, we argue for a broader understanding of brokerage success/failure, encompassing development outcomes. This comprehensive approach integrates both immanent and intentional factors in assessing development success or failure within the context of mining activitie