https://whangareiflora.weebly.com/kauri.html the pathogen – evolution to diagnostics

Richard Winkworth School of Fundamental Science https://www.doc.govt.nz/nature/pests-and-threats/diseases/kauri-dieback/kauri-dieback-programme/

what is kauri dieback?

a root and collar rot characterised by bleeding lower stem legions, crown thinning and tree death

first reported in 1972, but only after found on mainland was risk recognised

One Health (2020) what is agathidicida?

a soil-borne

causal agent of kauri dieback – highly aggressive pathogen of kauri but there are non-terminal hosts

One Health (2020) One Health (2020) http://idtools.org/id/phytophthora/factsheet.php?name=15150 P. infestans Ia P. infestans P. infestans IIa P. infestans IIb 0.96 P. mirabilis P. ipomoeae Clade 1 P. andina P. phaseoli P. nicotiniaea P. nicotiniaeb P. cactorum Plasmopara halstedii Clade 16 Bremia lactucae P. palmivoraa P. palmivorab Clade 4 P. litchii P. pluvialisa P. pluvialisb Clade 3 P. pseudosyringae Phytophthora is a large group of plant P. capsicia P. capsicib pathogens – currently 180 species but P. tropicalis P. subnubulis Clade 2 P. colocasiaea P. colocasiaeb discovery is accelerating a P. multivora P. multivorab P. agathidicidaa P. agathidicidab P. cocoisa Clade 5 is small, ~5 recognised taxa but P. cocoisb Clade 5 P. castaneae P. heveae further diversity is known P. sp. "novaeguineae" 0.98 P. tubulina P. versiformis Clade 12 P. quercina Peronospora tabacina diebacks of other species Peronospora effusa Peronospora belbahrii Pseudoperonospora humuli Clade 15 Haloperonospora arabidopsidis P. taxon totaraa P. taxon totarab at least 5 other Phytophthora as well as P. chlamydosporaa P. chlamydosporab P. gonapodyides Clade 6 several other reported from kauri 0.99 P. pinifolia P. fragariae P. rubi forest soils P. alni P. cambivora Clade 7 P. sojae P. cinnamomia P. cinnamomib P. ramoruma P. ramorumb P. lateralisa P. lateralisb Clade 8 P. sansomeana P. cryptogea P. fallax P. capitosa Clade 9 P. polonica P. kernoviaea Clade 10 P. kernoviaeb Nothophytophthora valdiviana Pythium ultimum

One Health (2020) “invasive” “native”

“released” “evolved” the pathogen arrives biotic or abiotic in New Zealand with the pathogen or host environments have “form” has changed changed becoming more making host “weaker” virulent/agressive or or pathogen more susceptible “stronger”?

One Health (2020) Raetea

Waipoua Forest (2)

Trounson Forest samples cover geographic range Arapohue Great Barrier Island (3) and were collected 1972-2014 Ruawai Pakiri

assembled whole mitochondrial Coromandel (2)

genomes for each Waitakere (Piha)

Waitakere (Huia, 3)

https://www.kauridieback.co.nz/kauri-maps/ One Health (2020) Far North

Kaipara + geographic structure and Coromandel suggests diversification began ~300 years ago Great Barrier Island not easily explained by an arrival post-WWII (i.e., 14 genotypes)

Auckland consistent with an arrival several hundred to perhaps several thousand years ago

https://www.kauridieback.co.nz/kauri-maps/ One Health (2020) https://johnkempf.com/thinking-deeper-on-the-disease-triangle/

biotic and abiotic

a “naturalised” pathogen, recent disease appearance may imply “release” due to habitat fragmentation, climate change, disturbance, new introductions

will our current management strategies still work?

One Health (2020) 1 week

current standard bioassay costs $100’s and 4+ weeks to complete, detection is subjective

testing only after disease appears but the lag period means that apparently healthy forest may be infected

we are playing catch up – and not very well 3 weeks

http://www.nzffa.org.nz/farm-forestry-model/the-essentials/forest-health-pests-and- diseases/diseases/Phytophthora/spotlight-on-new-species-of-phytophthora/ One Health (2020) 1 week

developed “hybrid” bioassay – advantages of baiting without disadvantages of plating

use a highly specific and highly sensitive LAMP assay to detect the pathogen from the bait

costs tens of dollars and takes a week – testing must still be conducted in a lab 3 weeks

http://www.nzffa.org.nz/farm-forestry-model/the-essentials/forest-health-pests-and- diseases/diseases/Phytophthora/spotlight-on-new-species-of-phytophthora/ One Health (2020) Phytophthora palmivora

Phytophthora pluvialis Phytophthora colocasiae

Phytophthora cinnamomi Trichophyton sp.

Pseudocercospora fijiensis

Paranannizziopsis australis Salmonid sp.

Austropuccinia psidii

One Health (2020) in side-by-side testing the hybrid bioassay outperforms the standard bioassay for 14 samples, LAMP detected 8 but only two were detected visually

for a collection of ~660 samples results are similar, 18 detected visually v. 82 using LAMP

https://www.kauridieback.co.nz/kauri-maps/ One Health (2020) ~2700 tests, ~1700 for P. agathidicida and ~1000 for P. cinnamomi

landscape level monitoring – of diseased and non-diseased sites using combination of soil and, now, water sampling includes working with Mana Whenua

https://ourauckland.aucklandcouncil.govt.nz/articles/news/2017 One Health (2020) /03/musical-campaign-to-help-kauri/ Prof. Peter Lockhart, Trish McLenachan, Briana Nelson

Stanley Bellgard, Lee Hill, Fredrik Hjelm

Ngā Maunga Whakahii o Kaipara Development Trust, Shona Oliver

Bio-Protection Research Centre Conference (2017)