Biocontrol introduction
Target pest: Tradescantia fluminensis (Commelinales: Commelinaceae), tradescantia, wandering willie, wandering jew
Agent introduced: Kordyana brasiliensis (Exobasidiales: Brachybasidiaceae), Brazilian yellow leaf spot fungus
Imported:
2017
Import source:
Brazil, via Australia
Import notes:
Landcare Research (2016i) - it is planned to import K. brasiliensis into containment in 2017.
Landcare Research (2018a) - CSIRO (Australia) imported K. brasiliensis as a biocontrol agent into their containment facility in Canberra, from where the New Zealand material was sourced.
Probst (2021) - Kordyana brasiliensis is native to Brazil. The fungus was imported into New Zealand from a CSIRO containment facility in Australia in 2017.
Released:
2018
Release details:
Landcare Research (2014c) - releases are likely to begin in 2015.
Landcare Research (2015i) - releases are on hold until the impact of the recently-released beetles (Neolema ogloblini, N. abbreviata, Lema basicostata) is known and the need for the fungus confirmed.
Landcare Research (2016i) - plan to import in 2017 so releases can begin.
Landcare Research (2017g) - first field releases planned for spring 2017.
Landcare Research (2018a) - all going well the first field release will take place at the end of February 2018 in the Auckland region.
Landcare Research (2018f) - the first release of the fungus was made in March 2018 in Rotorua, and releases have also been made in Waikato, Wellington and Tauranga (all sites in the North Island).
Landcare Research (2018i) - further widespread releases planned.
Landcare Research (2018h, 2019j) - seven releases made in the year Sep 2017 - Aug 2018, 24 in the year Sep 2018 - Aug 2019.
Landcare Research (2020b) - following the first release in Rotorua, subsequent releases have taken place in place in Northland, Waikato, Wellington, Auckland and Manawatū-Wanganui in the North Island, and the West Coast and Nelson in the South Island.
Landcare Research (2020h, 2021e, 2022h, 2023f) - six releases made in the year Sep 2019 - Aug 2020, 15 in the year Sep 2020 - Aug 2021, eight in the year Sep 2021 - Aug 2022, seven in the year Sep 2022 - Aug 2023.
Establishment:
Landcare Research (2018i) - already [Aug 2018] some promising signs of likely establishment seen.
Landcare Research (2020b) - at the Waingaro Valley (Waikato) release site, 10 weeks after release, tradescantia plants displayed characteristic yellow spots on the leaves, an indication of successful establishment. A year and a half later, in December 2019, the fungus has steadily spread, causing extensive defoliation of tradescantia. Cool, damp conditions at the Waingaro Valley site are ideal for the fungus; these conditions have not been seen elsewhere, with the fungus dying off at some release sites that have been too dry.
Landcare Research (2022g) - Kordyana brasiliensis is now well established in many parts of the North Island.
Impacts on target:
Landcare Research (2019i) - some promising damage seen already (Aug 2019) at one site in the Waikato.
Landcare Research (2020b) - at the Waingaro Valley (Waikato) release site in December 2019, a year and a half after release, K. brasiliensis is causing extensive defoliation of T. fluminensis.
Probst C (2021) - it is too soon to know what impact K. brasiliensis will have in New Zealand, on its own or in conjunction with the tradescantia beetles released against T. fluminensis [the leaf beetle, Neolema ogloblini, the tip beetle, N. abbreviata and the stem beetle, Lema basicostata]. However, the four agents are expected to complement each other, with the fungus assisting in cooler areas, and those prone to flooding, where the insects struggle to establish.
Landcare Research (2023g) - Kordyana brasiliensis is causing promising damage to T. fluminensis at several sites in the North Island.
Impacts on non-targets:
Auckland Council (2012) - there are no New Zealand native plants in the same order as T. fluminensis; arguably the closest native relative is the endemic palm Rhopalostylis sapida (nikau), which belongs to a different order. Host range testing was carried out in Brazil; T. fluminensis and 20 non-target plants were tested. Kordyana sp. only caused symptoms on T. fluminensis. These results demonstrate that the fungus is highly host specific. Given the inability of Kordyana sp. to infect any species other than T. fluminensis, and the taxonomic distance between T. fluminensis and New Zealand native plants, it is extremely unlikely that Kordyana sp. could damage any non-target native or ornamental plants in New Zealand.
Landcare Research (2020b) - at the Waingaro Valley (Waikato) release site in December 2019, a year and a half after release, K. brasiliensis has caused extensive damage to tradescantia, which had dominated the forest floor, allowing the seeds of native plants to germinate. The seedlings of the endemic tree, kahikatea (Dacrycarpus dacrydioides), are now starting to outnumber tradescantia plants at the original release site.
General comments:
Taxonomic note (30 June 2016) - Macedo et al. (2016) described this species as Kordyana brasiliensis.
EPA Applications:
EPA (2013b) - 10 Sep 2012: application by Auckland Council on behalf the National Biocontrol Collective to import and release Brazilian yellow leaf spot fungus [as Kordyana sp., a previously undescribed species, and subsequently described as K. brasiliensis (see General Comments)] as a biocontrol agent for wandering willie. EPA Application #201362. Approved without controls 31 Jan 2013.
References
Auckland Council (2012). EPA application [APP201362] to import for release or to release from containment new organisms [Kordyana sp.]. Environmental Protection Authority website https://www.epa.govt.nz/assets/FileAPI/hsno-ar/APP201362/b8c51ddc29/APP201362-APP201362-Application.pdf
EPA (2013b). EPA application APP201362: to import and release the pathogen Kordyana sp. as a biological control agent for the weed Tradescantia fluminensis. Environmental Protection Authority website https://www.epa.govt.nz/database-search/hsno-application-register/view/APP201362
Landcare Research (2014c). Who's who in biocontrol of weeds? What's new in biological control of weeds? 69: 10-11 https://www.landcareresearch.co.nz/assets/Publications/Weed-biocontrol/WhatsNew69.pdf
Landcare Research (2015i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 73: 10-11 http://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-73
Landcare Research (2016i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 77: 10-11 http://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-77
Landcare Research (2017g). Who's who in biological control of weeds? Weed Biocontrol: What's New? 81: 10-11 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-81
Landcare Research (2018a). First release of new agents. Weed Biocontrol: What's New? 83, February 2018 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-83/first-release-of-new-agents
Landcare Research (2018f). Tradescantia be gone! Weed Biocontrol: What's New? 84, May 2018 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-84/tradescantia-be-gone
Landcare Research (2018h). Biocontrol agents released in 2017/18. Weed Biocontrol: What's New? 85, August 2018 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-85/biocontrol-agents-released-in-201718
Landcare Research (2018i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 85, August 2018 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-85/whos-who-in-biological-control-of-weeds
Landcare Research (2019i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 89, August 2019 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-89/whos-who-in-biological-control-of-weeds
Landcare Research (2019j). Biocontrol agents released in 2018/19. Weed Biocontrol: What's New? 89, August 2019 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-89/biocontrol-agents-released-in-201819
Landcare Research (2020b). Biocontrol success in the Waingaro Valley. Weed Biocontrol: What's New? 91, February 2020 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-91/biocontrol-success-in-the-waingaro-valley
Landcare Research (2020h). Further reading and agents released table. Weed Biocontrol: What's New? 93, Aug 2020. https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading-and-agents-released-table/
Landcare Research (2021e). Further reading and agents released. Weed Biocontrol: What's New? 97, August 2021 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading
Landcare Research (2022g). Spring activities. Weed Biocontrol: What's New? 101, August 2022 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/spring-activities-3/
Landcare Research (2022h). Further reading and agents released 2021/22. Weed Biocontrol: What's New? 101, August 2022 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading-and-agents-released-202122/
Landcare Research (2023f). Further reading and biocontrol agents released in 2022/23. Weed Biocontrol: What's New? 105, August 2023. https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading-and-agents-released
Landcare Research (2023g). Who's who in the biological control of weeds. Weed Biocontrol: What's New? 105, August 2023 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/whos-who/
Macedo DM, Pereira OL, Hora Júnior BT, Weir BS and Barreto RW. (2016). Mycobiota of the weed Tradescantia fluminensis in its native range. Australasian Plant Pathology 45: 45-56
Probst C (2021). Tradescantia yellow leaf spot fungus: Kordyana brasiliensis. The Biological Control of Weeds Book - Te Whakapau Taru: A New Zealand Guide (Landcare Research) https://www.landcareresearch.co.nz/discover-our-research/biodiversity-biosecurity/weed-biocontrol/projects-agents/biocontrol-agents/tradescantia-yellow-leaf-spot-fungus/
