Miss Zoe King1, Professor Hannah Buckley1, Professor Gavin Lear2, Associate Professor Brent Seale1, Dr Kevin C. Lee1, Professor Donnabella Lacap-Bugler1
1School of Science, Auckland University of Technology, Auckland, New Zealand, 2School of Biological Sciences, University of Auckland, Auckland, New Zealand
Biography:
Zoe King is a PhD candidate at Auckland University of Technology. Interested in bioinformatics and microbial ecology, she is researching the soil microbial community surrounding kauri trees affected by dieback disease.
Abstract:
Kauri (Agathis australis) are coniferous trees holding immense significance to the people and ecosystems of Aotearoa. This iconic species is currently under threat from a root-rotting disease caused by the soil-borne Oomycete, Phytophthora agathidicida. Prolonged infection of kauri by P. agathidicida will always lead to the death of the tree. With no known cure for this disease, the longevity of this iconic tree species is under threat. The Waitākere Ranges in Auckland, New Zealand, is one of the most heavily affected areas of kauri dieback, making it an ideal region for long-term surveillance of this disease. In 2012, several disease monitoring plots were established in this region, however, characterisation of the soil microbial community has been neglected. To understand how the microbial community is associated with the health of this keystone species, 96 kauri trees were randomly selected from six long-term monitoring plots for cardinal point soil sample collection. Environmental DNA was extracted from the 384 soil samples and shotgun metagenomic sequencing was performed on an Illumina NovaSeq system. Sampled trees were categorised into three different tree health statuses: healthy, defoliated, and dead; based on their canopy health. Multivariate analysis showed that the bacterial community composition and functional potential varied among these three different tree health statuses. Results from this study provide a baseline of the structure and functional potential of the soil microbial community surrounding kauri of different health statuses. This baseline can be used to understand and predict interactions between kauri tree health and soil microbial communities.