ABSTRACTSoil‐borne pathogens can influence microbial communities and ecosystem function, making it important to understand their broader ecological impacts. We investigated interactions between Phytophthora agathidicida (the causal agent of kauri tree dieback) and soil microbial communities, while also comparing detection and community‐profiling methods. Soils from 60 kauri trees across three sites in the Waitākere Ranges, New Zealand, were analysed using loop‐mediated isothermal amplification (LAMP) for pathogen detection, and 16S rRNA gene/ITS gene amplicon sequencing alongside shotgun metagenomics for community characterisation. LAMP detected P. agathidicida in 39/60 samples, while shotgun sequencing detected Phytophthora‐associated DNA at low abundance across all samples. Microbial community structure and functional potential showed weak association with pathogen presence, though differential abundance testing identified several genera enriched in pathogen‐detected soils, including taxa previously linked to disease suppression. Amplicon and shotgun profiles indicated broadly comparable patterns at higher taxonomic and functional levels, while differences between approaches emerged primarily at finer taxonomic resolution. Importantly, functional predictions from PICRUSt2 closely matched shotgun‐derived profiles at broader scales, indicating its suitability as a cost‐effective tool for broad‐scale monitoring. These findings suggest limited direct pathogen effects on microbial communities and highlight how integrating molecular approaches provides complementary insights into soil microbiome‐pathogen interactions.

Kauri (Agathis australis) is a culturally and ecologically important conifer native to Aotearoa New Zealand. It is currently threatened by a dieback disease caused by the soil-borne pathogen Phytophthora agathidicida. The relationship between the plant and its endophytes plays a crucial role in plant growth, host resilience, physiology, and defence mechanisms. This research investigates the potential role of endophytes in supporting systems, particularly concerning kauri dieback disease. The study focuses on identifying and characterizing the endophytic fungi and bacteria associated with the roots of cutty grass (Carex geminate) and kauri grass (Astelia trinervia), which are companion plants in kauri forests found at both diseased and healthy sites. These companion plants are closely associated with kauri and serve as promising models due to their abundance. A total of 61 endophytes were isolated from the roots of both plants using different media. The colony and cell morphology of these isolates were examined, and they were identified as putative Fusarium, Penicillium, Trichoderma, and Aspergillus species. The full 16S rRNA gene and internal transcribed spacer (ITS) region analyses confirmed the phylogenetic identities of the endophytes. Some isolates demonstrated antagonistic effects against Phytophthora agathidicida via dual culture assays. Bioactive metabolites from these endophyte isolates will be extracted for further analysis. This study aims to explore whether root endophytes of companion plants could contribute to biocontrol strategies for combating kauri dieback. This research provides novel insight into mitigating plant pathogens in native forests and ecosystems using companion plants hence, preserving forest integrity.

Agathis australis (kauri), the only member of the ancient conifer family Araucariaceae in New Zealand, is colonised by arbuscular mycorrhizal (AM) fungi. The survival of A. australis is threatened by an Oomycota, Phytophthora agathidicida , the causal agent of kauri dieback. Phosphite injections into the trunk are the primary treatment for kauri dieback and have proven effective in reducing disease symptoms. However, the potential impact of phosphite treatment on AM fungal colonisation within A. australis roots and nodules has not been investigated. We conducted a preliminary investigation into whether AM fungi colonise phosphite‐treated trees. Using a combination of microscopy and metabarcoding of AM fungi 18S nuclear ribosomal small subunit genes, we demonstrate that AM fungi colonise the roots and nodules of A. australis trees three to 4 years post‐treatment. Glomeraceae was found to dominate, and AM fungi community composition and colonisation rates were comparable to previously reported values in trees not treated with phosphite. Soil pH, but not date of phosphite treatment or PA infection status, was found to significantly contribute to AM fungal community composition. This work highlights the importance in investigating colonisation events immediately after phosphite treatment of A. australis and a comparison with untreated trees. AM fungi are likely integral for A. australis forests to thrive, thus, ensuring they are protected in the treatment of kauri dieback is essential.

This research investigates how the soundscape of Native forests reflects forest health and how it may signal early signs of Kauri Mate ( Phytophthora agathidicida ; dieback) infection. Grounded in mātauranga Māori (Māori [the Indigenous peoples of New Zealand] knowledge) from Te Rarawa (a tribe in the northern North Island, New Zealand), the study combines Indigenous knowledge with modern technology to develop a sonic-based method for ecological restoration. Recorded soundscapes from healthy kauri (a coniferous tree, northern New Zealand; Agathis australis ) are layered with taonga puoro (traditional Māori instruments), karakia (chants), and parāoa (sperm whale) calls, blended with the 528 Hz healing frequency to create immersive environments aligned with the forest’s mauri (life force). This methodology acknowledges the interconnectedness of all living entities and aims to restore ecosystems through vibration and sound. Findings recommend community-led, culturally grounded soundscape interventions to support forest health, while strengthening spiritual and emotional connections between people, place, and environment.

Abstract Native forests in Aotearoa/New Zealand are at significant risk from the plant diseases myrtle rust and kauri dieback. Mobilising for Action (MFA) was a four-year transdisciplinary research project exploring the social dimensions of these pathogens and forest health through social science, humanities, creative arts and mātauranga Māori (Māori knowledge), with experts, artists, iwi/hapū (tribes/sub-tribes) and communities, empowering and supporting them in their efforts to address forest disease and promote forest health. A waka houora (double-hulled canoe) framework guided MFA to enable Western knowledge systems to operate alongside mātaurangā Māori, allowing for collaboration, cross-cultural learning and Indigenous empowerment through artistic research and related approaches. We propose that through various creative arts approaches, MFA built relationships and partnerships between Māori and other cultures, people and forests and disciplines, in addition to developing novel research methods in forest health through storytelling and narratives, offering new possibilities in critical forest studies and care.

Kauri dieback is a soil-borne pathogen of the family Phytophthora which is lethal to kauri trees. Despite its risks, residents of New Zealand often do not follow imposed mitigation strategies. In this study we explored the potential impact of three factors on psychological distance to kauri dieback: pro-environmental worldviews, trust in government and physical distance from kauri forests. We also investigated the extent to which previously validated psychological distance measures predicted kauri forest visitors' compliance with boot-cleaning and trail-usage guidelines (behaviours linked to the spread of kauri dieback). A survey assessing beliefs and behaviours related to kauri dieback was completed by a sample of 451 New Zealand residents who had visited a kauri forest in the past four years. Two path analyses were conducted to determine whether the effects of environmental worldview (NEP score), trust in government, and physical distance on boot cleaning and track use compliance behaviours were mediated by psychological distance. Direct effects indicated that higher NEP score and closer physical distance significantly reduced psychological distance, but trust in government did not. Closer psychological distance also significantly improved self-reported track use and boot cleaning behaviours. Indirect effects indicated that psychological distance significantly mediated the effects of worldview, trust and physical distance on boot cleaning and track usage. Several significant direct effects of the exogenous predictors on the compliance behaviours were present after controlling for the mediator, indicative of partial mediation. Psychological distance is a reliable predictor of respondents' boot-cleaning and track-use compliance. Interventions to decrease psychological distance may be beneficial for increasing compliance, although the effects were modest and other potential determinants of compliance also require investigation.

BackgroundKauri dieback is a soil-borne pathogen of the family Phytophthora which is lethal to kauri trees. Despite its risks, residents of New Zealand often do not follow imposed mitigation strategies. In this study we explored the potential impact of three factors on psychological distance to kauri dieback: pro-environmental worldviews, trust in government and physical distance from kauri forests. We also investigated the extent to which previously validated psychological distance measures predicted kauri forest visitors’ compliance with boot-cleaning and trail-usage guidelines (behaviours linked to the spread of kauri dieback).MethodsA survey assessing beliefs and behaviours related to kauri dieback was completed by a sample of 451 New Zealand residents who had visited a kauri forest in the past four years. Two path analyses were conducted to determine whether the effects of environmental worldview (NEP score), trust in government, and physical distance on boot cleaning and track use compliance behaviours were mediated by psychological distance.ResultsDirect effects indicated that higher NEP score and closer physical distance significantly reduced psychological distance, but trust in government did not. Closer psychological distance also significantly improved self-reported track use and boot cleaning behaviours. Indirect effects indicated that psychological distance significantly mediated the effects of worldview, trust and physical distance on boot cleaning and track usage. Several significant direct effects of the exogenous predictors on the compliance behaviours were present after controlling for the mediator, indicative of partial mediation.ConclusionsPsychological distance is a reliable predictor of respondents’ boot-cleaning and track-use compliance. Interventions to decrease psychological distance may be beneficial for increasing compliance, although the effects were modest and other potential determinants of compliance also require investigation.

ABSTRACTPhytophthora agathidicida, a plant pathogenic oomycete, causes fatal dieback disease in New Zealand kauri trees (Agathis australis). Currently, few treatments exist to prevent or cure this infection. Previous research has demonstrated the potent in vitro inhibition of multiple lifecycle stages of P. agathidicida by the oomycide oxathiapiprolin. In this study, we have evaluated the efficacy of oxathiapiprolin in planta as either a protective or curative treatment. Kauri seedlings (1–2 years old) were treated with 10 or 50 mg of oxathiapiprolin, in the form of Zorvec Enicade, per seedling as a soil drench either before (7 days) or after (15 days) inoculation with P. agathidicida NZFS 3770 to test for protective and curative activities, respectively. Results showed that oxathiapiprolin treatments successfully protected the kauri seedlings from disease, with the higher dose (50 mg) demonstrating greater efficacy. However, the treatments did not cure kauri seedlings already infected with P. agathidicida, likely because the infection was already well‐established by the time of treatment. This study demonstrates that, while oxathiapiprolin shows protective effects against P. agathidicida infection in kauri seedlings, its lack of curative properties significantly limits its potential as a practical tool for managing kauri dieback disease.

ABSTRACTDisease caused by plant pathogens can shape plant community structure and composition, especially if the host species plays important ecological roles. The New Zealand kauri, Agathis australis, is a foundation species that modifies its soil environment and, by doing so, it acts as an ecological filter selecting for a distinctive suite of plant species that co‐occur preferentially with it. Kauri is threatened by kauri dieback disease caused by Phytophthora agathidicida. Despite kauri's ecological importance in structuring plant communities, little is known about the consequences of kauri dieback on the plant species ecologically associated with kauri—kauri associates. This study examined (1) the environmental drivers of diseased kauri occurrences, (2) the correlations between the occurrences of kauri associates and environmental factors and (3) which kauri associates frequently co‐occurred with diseased kauri as a result of shared environmental responses. A joint species distribution model with nine environmental factors was used to analyse the occurrences of diseased kauri and 16 kauri‐associated plant species located within a 10‐m radius of 761 kauri trees in lowland kauri‐podocarp‐broadleaved forests of Waitākere Ranges, Auckland, New Zealand. Our results showed that diseased kauri occurred more frequently in sites at lower elevation, with shallower organic soil layers and a history of logging or timber processing disturbance. Additionally, successional strategies influenced the relationship between kauri associate occurrences and environmental factors, with kauri associates characteristic of early succession frequently co‐occurring with diseased kauri due to environmental factors. This suggests that kauri dieback could either cause the retrogression of succession in kauri forests or that kauri in younger stands were more likely to be diseased. Both of these possibilities indicate that kauri dieback would likely change the successional trajectory of kauri forests. Future studies should integrate longitudinal demographic data with disease progression to investigate the mechanistic effects of disease on kauri community dynamics.

Phytophthora species are notorious plant pathogens responsible for severe dieback and root rot diseases, significantly impacting crops, forests, and irreplaceable natural ecosystems. Rapid and accurate detection of these pathogens is essential for effective disease management. In New Zealand, P. agathidicida threatens the country's endemic kauri forests. In this study, we developed and validated a PCR-based method for detecting P. agathidicida oospores in soil. Oospores are long-lived, thick-walled spores that serve as key propagules for survival in soil and the spread of disease. Their robust structure and dormant state make them particularly challenging to detect using traditional soil baiting techniques or DNA-based methods. Our method is fast, accurate, and requires minimal equipment, enabling local testing and thereby empowering communities and enhancing surveillance efforts. Although developed for P. agathidicida, this method could be adapted for other plant pathogens, potentially improving disease management across various agricultural and ecological contexts.

Phytophthora species are eukaryotic plant pathogens that cause root rot and dieback diseases in thousands of plant species worldwide. Despite their significant economic and ecological impacts, fundamental molecular tools such as DNA transformation methods are not yet established for many Phytophthora species. In this study, we have established a PEG/calcium chloride (CaCl2)-mediated protoplast transformation method for Phytophthora agathidicida, the causal agent of kauri dieback disease. Adapting a protocol from Phytophthora sojae, we systematically optimized the protoplast digesting enzymes, recovery media composition and pH. Our findings reveal that chitinases are essential for P. agathidicida protoplast formation, and the optimum pH of the recovery medium is 5. The media type did not significantly impact protoplast regeneration. Using this protocol, we generated transformants using three plasmids (i.e. pTdTomatoN, pYF2-PsNLS-Cas9-GFP and pYF2-PsNLS-Cas12a-GFP), which expressed fluorescent proteins and/or Cas nucleases. The transformants were unstable unless maintained under antibiotic selective pressure; however, under selection, fluorescence was maintained across multiple generations and life cycle stages, including the production of fluorescent zoospores from transformed mycelia. Notably, we observed the expression of GFP-tagged Cas nucleases, which is promising for future CRISPR-Cas genome editing applications. This study demonstrates that P. agathidicida is amenable to PEG/CaCl2-mediated protoplast transformation. Although the resulting transformants require antibiotic selective pressure to remain stable, this transient expression system can be valuable for applications such as cell tracking, chemotaxis studies and CRISPR-Cas genome editing. The protocol also provides a foundation for further optimization of transformation methods. It serves as a valuable tool for exploring the molecular biology of P. agathidicida and potentially other closely related Phytophthora species.

Phosphite (HPO32–) is an effective chemical treatment used to manage Phytophthora diseases in natural and horticultural environments. In New Zealand it is applied as a trunk injection to protect the threatened endemic foundation tree, Agathis australis (kauri), from the invasive pathogen P. agathidicida. It is applied as a foliar spray in natural ecosystems in Australia to protect against a range of Phytophthora-associated diseases and retain plant biodiversity and abundance. Foliar spray application could be a useful method for broad area treatment and to protect isolated and difficult-to-reach stands of kauri, or in plant production settings. In this study, we assessed the efficacy of phosphite when applied as a foliar spray to inhibit P. agathidicida colonisation, the phytotoxicity response and whether the phosphite was translocated to the roots using two glasshouse experiments with 2- and 6-year-old kauri plants. The foliar phosphite treatment effectively reduced colonisation by P. agathidicida in the 2-year-old plants and elevated concentrations of phosphite in the roots of the 6-year-old plants were detected. Phytotoxicity increased with increasing phosphite concentration in both trials. The addition of the surfactant Du-Wett® reduced phytotoxicity for older leaves in the 6-year-old plants. In both assays, phytotoxicity symptoms were most severe on young leaves but had no effect on the production of fresh growth following treatment, suggesting that any ill effects were short-lived. This study indicates that phosphite foliar sprays may be an effective tool to manage kauri dieback under the appropriate circumstances.

Safeguarding Iconic Tree Species, Dependent Ecosystems, and Regional Economies: A New Zealand Perspective on Controlling Kauri Dieback

ABSTRACTAimsUnderstanding the impacts of forest tree pathogens on understorey sapling populations is critical for understanding their population‐level effects and the likely successional trajectories of infected communities. We assessed the impacts of Phytophthora agathidicida, a soil‐borne pathogen, on the sapling population dynamics of the disease‐susceptible, locally dominant canopy tree, the conifer kauri (Agathis australis, Araucariaceae). We also examined the indirect effects of P. agathidicida on likely resistant allospecifics that span a range of shade‐tolerances as saplings, to predict future successional trajectories.LocationWaitākere Ranges, west of Auckland, Aotearoa‐New Zealand.MethodsWe analysed data from four kauri‐dominated permanent plots in Aotearoa‐New Zealand warm temperate rain forests. Two plots were early‐successional and two were late‐successional, one in each pair had overstorey kauri showing intense visual P. agathidicida symptoms, and the other overstorey kauri showing few symptoms. We examined the association between kauri trees and saplings using point pattern analysis and the relationship between the level of crowding around saplings and their growth and survival rates. We compared the growth and survival rates of kauri and allospecifics, categorised by shade tolerance, among the plots.ResultsKauri forms sapling banks under conspecific trees that were less dense in late‐successional forests and in those where the overstorey kauri showed symptoms of P. agathidicida infection. Despite having lower densities, kauri sapling growth rates were higher in symptomatic plots. The growth rates of light‐demanding allospecifics were also higher in these plots, with minor differences in mortality and growth rates for more shade‐tolerant allospecifics. P. agathidicida may promote sapling growth and survival of kauri and some allospecifics in infected plots.ConclusionsSapling vital rates and population sizes differed between asymptomatic and symptomatic plots, particularly in early‐successional settings, where P. agathidicida may reset succession in early‐successional communities back to those dominated by species that first colonised after disturbance.

This chapter describes the protocol for heterologous expression of Phytophthora proteins in the yeast Pichia pastoris. Two methods to prepare the constructs for expression are described, using two different strains of P. pastoris, as well as methods for protein expression and purification by immobilized metal ion affinity (IMAC). The combined protocol was used to successfully produce a Phytophthora pluvialis small, secreted cell death elicitor protein and a Phytophthora agathidicida glycoside hydrolase 12, PaXEG1, also a cell death-inducing protein.

Kauri forests are threatened by kauri dieback disease, caused by the microscopic soil-borne pathogen Phytophthora agathidicida (PA). Despite it being more than 15 years since the pathogen was discovered on the New Zealand mainland, there is still a paucity of information on the distribution of symptomatic trees and/or of the pathogen itself, which makes it challenging to understand where the infection foci are and how fast the pathogen is spreading. The considerable cost of surveillance for PA, as well as the risks associated with people walking between infected and non-infected sites, necessitates careful prioritisation of sites to be selected for surveillance. This task requires an understanding of which part of the landscape and how much of it needs to be surveyed to effectively detect the pathogen if present. We use information on the distribution of kauri trees with visible stress symptoms in the canopy to develop a baseline relative risk map depicting areas where PA is most likely to be present for three kauri forests in Northland, New Zealand. The relative risk map provides a simple, yet effective management tool to target trees for surveillance, monitoring, and protection. Using this insight, we demonstrate the application of a proof of absence statistical model to determine the surveillance effort required to be confident that if no PA is found during surveillance in selected priority sites, the pathogen can confidently be considered absent from these areas. Results from these analyses showed that many samples are needed to achieve 95% confidence in pathogen absence, but this varied between forests and sectors of each forest. However, these analyses are valuable to guide field efforts as well as to ensure realistic expectations among practitioners. The methods described here are applicable to many other pathogens affecting plants of cultural and/or ecological importance worldwide.

Leaf surface microbial communities play an important role in forest ecosystems and are known to be affected by environmental and host conditions, including diseases impacting the host. Phytophthora agathidicida is a soil-borne pathogen that causes severe disease (kauri dieback) in one of New Zealand’s endemic trees, Agathis australis (kauri). This research characterised the microbial communities of the A. australis phyllosphere (i.e. leaf surface) using modern molecular techniques and explored the effects of P. agathidicida on those communities. Fresh leaves were collected from trees where P. agathidicida was and was not detected in the soil and characterisation of the leaf surface microbial community was carried out via high-throughput amplicon sequencing of the internal transcribed spacer (ITS) and 16S ribosomal RNA regions. Nutrients in leaf leachates were also measured to identify other possible drivers of microbial diversity. The dominant phyllosphere microbial phylum was Proteobacteria followed by Acidobacteria. The phyllosphere microbial richness of A. agathis associated with P. agathidicida-infected soils was found to be generally lower than where the pathogen was not detected for both prokaryote (bacterial) and fungal phyla. Leaf leachate pH as well as boron and silicon had significant associations with bacterial and fungal community structure. These findings contribute to the development of a comprehensive understanding of A. australis leaf surface microbial communities and the effects of the soil pathogen P. agathidicida on those communities.

Phytophthora are causing declines in forest tree species worldwide and the chemical control treatment, phosphite, is the only treatment consistently shown to provide some protection to natural ecosystems from Phytophthora diseases. Phosphite inhibits Phytophthora growth and sporulation whilst boosting defence responses in the plant host. It is unclear, however, the extent of the impact of phosphite on Phytophthora species assemblages and inoculum abundances in soil around trees following treatment within natural ecosystems. In New Zealand, kauri (Agathis australis), an endemic and threatened foundation species, suffers from a dieback disease primarily caused by Phytophthora agathidicida. Phosphite is applied by trunk injection to kauri and has been shown to improve resin ‘bleed’ symptoms from basal trunk lesions and to promote recovery of thinned canopies. Phytophthora community and inoculum abundance were investigated in response to phosphite treatments at two field sites (Huia and Waitoki) in infected kauri stands in Auckland, New Zealand. At Huia, soil sampling and tree health surveying were conducted in November 2023 on trees treated with phosphite in 2012 as part of an earlier study. At Waitoki, the response to phosphite treatment was monitored 6 and 18 months following treatment. Phytophthora species were detected using soil baiting and metabarcoding of Environmental DNA (eDNA) from soil and quantified with qPCR of root and soil DNA. Three species were detected with soil baiting (P. agathidicida, P. cinnamomi, and P. multivora) and two additional species with metabarcoding (P. pseudocryptogea, and an unknown clade 7 species similar to P. europaea). Phytophthora cinnamomi was the most abundant species, followed by P. agathidicida. Both species were more likely to occur together than by chance alone and were associated with declining tree health. The P. europaea-like species was in approximately 50 % of the samples and was less likely to occur in roots with poorer health, or in association with P. agathidicida. The abundance of P. agathidicida inoculum was lower in the soil around the phosphite-treated trees than around the untreated control trees 1.5 years after treatment at Waitoki. Phosphite halted the lateral expansion of basal resin bleeds, and resin viscosity was reduced. Not only did phosphite treatments improve kauri dieback symptoms, but the phosphite treatments potentially had a direct impact on the epidemiology of the disease by reducing inoculum load around treated trees, with direct implications for disease management as an effective way to protect uninfected areas and minimise the spread of inoculum from infested zones.

Realising behavioural change in long invested environmental practices is often difficult to achieve, especially when scientific understanding of the issues is still unfolding. Having confidence in one’s action requires knowledge that actions will be effective in improving environmental outcomes. Currently, we know little about the role of social trust in mediating complex and uncertain knowledge of environmental problems and the required actions needed to address them. In this quantitative study, we surveyed 472 users of endangered kauri forests in New Zealand to better explore the role of trust in relation to pro-environmental behaviours (PEB) designed to mitigate effects of the devastating plant disease, kauri dieback. Findings show uncertainty about the scientific knowledge of the issue, recommended actions and efficacy of proposed solutions significantly influenced PEB for both residents and visitors of forests; however, this relationship was partially mediated by trust, particularly among locals residing within 5 km of infected forest areas. These findings indicate the need for closer engagement with local residents to develop institutional and scientific trust in kauri dieback interventions. We outline activities that may help build trust and recommend new areas of research to support higher compliance with environmental protection initiatives.

BackgroundThe ancient kauri (Agathis australis) dominated forests of Aotearoa New Zealand are under threat from a multitude of ecological disturbances such as forest fragmentation, biodiversity loss, climate change, and the spread of the virulent soil pathogen Phytophthora agathidicida. Taking a wider ecosystem-level approach, our research aimed to explore the impacts of forest disturbance and disease outbreaks on the biosynthetic potential and taxonomic diversity of the kauri soil microbiome. We explored the diversity of secondary metabolite biosynthetic gene clusters (BGCs) in soils from a range of kauri forests that varied according to historical disturbance and dieback expression. To characterise the diversity of microbial BGCs, we targeted the non-ribosomal peptide synthetase (NRPS) and polyketide synthetase (PKS) gene regions for sequencing using long-read PacBio® HiFi sequencing. Furthermore, the soil bacterial and fungal communities of each forest were characterized using 16 S rRNA and ITS gene region sequencing.ResultsWe identified a diverse array of naturally occurring microbial BGCs in the kauri forest soils, which may offer promising targets for the exploration of secondary metabolites with anti-microbial activity against P. agathidicida. We detected differences in the number and diversity of microbial BGCs according to forest disturbance history. Notably, soils associated with the most undisturbed kauri forest had a higher number and diversity of microbial NRPS-type BGCs, which may serve as a potential indicator of natural levels of microbiome resistance to pathogen invasion.ConclusionsBy linking patterns in microbial biosynthetic diversity to forest disturbance history, this research highlights the need for us to consider the influence of ecological disturbances in potentially predisposing forests to disease by impacting the wider health of forest soil ecosystems. Furthermore, by identifying the range of microbial BGCs present at a naturally high abundance in kauri soils, this research contributes to the future discovery of natural microbial compounds that may potentially enhance the disease resilience of kauri forests. The methodological approaches used in this study highlight the value of moving beyond a taxonomic lens when examining the response of microbial communities to ecosystem disturbance and the need to develop more functional measures of microbial community resilience to invasive plant pathogens.