sign in sign up
<<
Home , Lenwebbia, Pilidiostigma, Rhodamnia, Rhodamnia rubescens, Stockwellia, Ugni

Overview of myrtle rust response in ; Impact on rubescens and Rhodomyrtus psidioides

Angus J. Carnegie Guava rust Eucalyptus rust

Ohia rust Myrtle rust What’s in a name?

• (Winter 1884): echinulate urediniospores • Many synonyms (~25) – “novel” species described from many hosts as Puccinia (sexual state) or Uredo (asexual state) • In 2006 Simpson et al. described Uredo rangelii, based on tonsure on urediniospores (from only two herbarium specimens) – Identified as Uredo rangelii when arrived in Australia

Urediniospores & Teliospores

J. Walker (1983)

• Now accepted as Austropuccinia psidii – Single strain in Australia Australia’s Biosecurity System

• Emergency Pest Response Deed (“the Deed”) – Provides the framework for managing Exotic Plant Pest (EPP) incursions – Cost-sharing (Government / Industry)

• PLANTPLAN – Technical response plan used by jurisdictions and industry in responding to an EPP incident – Provides nationally consistent guidelines for response procedures under the Deed – Outlines the Phases of an incursion response • Investigation, Alert, Response, Stand Down – Key roles and responsibilities of industry and government Australian myrtle rust Emergency Response - Stages • Stages of myrtle rust response 1. Detection, initial surveys, stand down [1 week] 2. NSW Response (not under the Deed) [minimal resources] 3. National Response (under the Deed) [large resources] 4. Transitional Management (living with it)

Stage 1 Stage 2 Stage 3 Stage 4

April May June July August September October November December January 2010 2011

Carnegie & Cooper (2011) Australasian Plant Pathology 40: 446-459. Emergency Response – Stage 1

• Rust on Agonis flexuosa detected by grower 21 April – Identified by national expert 23 April – Surveys of IP1 24 April • 1100 Agonis , windbreak • Consultative Committee EPP convened 27 April – “Require more information to make an informed decision” • Surveys continue – 25 sites; nurseries, native bush, road-sides, gardens; 2 survey teams IP1 • IP2 detected (nursery 8.5 km from IP1) • CCEPP re-convened 30 April – “myrtle rust not technically feasible to eradicate” • National response stood down 30 April IP2

21 22 23 24 25 26 27 28 29 30 Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Infected Premises (IP) 1 Emergency Response – Stage 2

• NSW land management agencies agree to continue containment and surveillance – Outside of the Deed & cost-sharing arrangements – May & June 2010 – Minimal resources • Interim Response Plan (CCEPP) • Plant Health Australia request CCEPP to reconsider decision – Decision to stand down too hasty • Surveillance: – 85 site visits; 55 sites (multiple visits, especially IPs) – 5 Infected Premises detected • 4 with small number of plants infected IP1 • Containment: – Informal quarantine on properties – IP1: continued fungicide regime and surveys • Infected plants & NOT destroyed IP2 – IP2 to IP5: plants destroyed and fungicide regime • Tracing: some track back and trace forward IP4 – No indication of original source IP3 – Some links between infected premises IP5 Emergency response – Stage 3

• Observations from Stage 2 indicated rust had not behaved as expected – Limited spread, limited hosts, not spread to native bush, good containment on infected premises • Decision to go into full-blown emergency response – Under the PLANTPLAN & the DEED (costs covered) – Quarantine (restrictions on movement of ) – Tracing (>20,000 traces identified and processed) – Surveillance (>1,600 sites surveyed) – Containment & destruction (16,000 plants destroyed) – Communication & education campaign – Resources: 350+ staff

Stand Down - final

• 2nd December CCEPP reviewed status – Increasing host range – Spread beyond Central Coast: • Large number of domestic, commercial, public & recreational sites • Native vegetation and forests – Wind-borne spread • NMG 22nd December: not technically feasible to eradicate Emergency response time-line

Human-assisted transfer

200

180

160

focus -

140

120

Weather changes Weather Bushland 100

80

Austromyrtus

Emergency response restarts response Emergency

Detection Surveillance ramps up ramps Surveillance

60 Down Stood Cumulative number of IPs

40

20

0 April May June July August September October November December 2010 Key lessons

• “Surveillance and eradication procedures should be implemented immediately” • Coordinated and well resourced response protocols – Speedy process & firm decisions – Strong (pre-arranged) links with industry and peak interest groups • Industry need to be prepared for emergency response • Appropriate length for Investigation and Alert phase (before decision is made to proceed or stand down) – Initial investigative stage need to be well resourced • Uredo rangelii & myrtle rust caused confusion • Staff need to be identified pre-incursion and accessible during incursion – Pathologists, botanists, biosecurity/surveillance • Training in emergency response procedures • Assume all species of Myrtaceae are a host • Don’t assume myrtle rust symptoms are easy to detect • Difficult to predict which species will be significantly impacted Distribution in Australia

Berthon et al. (under review) Biological Conservation Rapidly expanding host range

• Prior to reaching Australia (1884–2010): – 130 species, 33 genera, 9 tribes Acca Beaufortia Eremaea Agonis Callistemon Eucalyptus • Australia (2010–2013): Calothamnus – 270 species, 51 genera, 15 tribes (naïve hosts) Angophora Calycorectes 300 Archirhodomyrtus Campomanesia Heteropyxis Astartea NATIONALField & laboratory Asteromyrtus Choricarpia Hypocalymma 250 Kunzea FIELDField - NATIONALonly Backhousia Lenwebbia 200 Barongia Decaspermum Leptospermum Lindsayomyrtus Osbornia Stockwellia 150 Lithomyrtus Pericallyma Syncarpia

Number Pilidiostigma Syzygium

100 Lophostemon Pimenta Thryptomene Melaleuca Plinia Tristania

Number of host species of host Number Metrosideros Tristaniopsis 50 Psidium Mitrantia Regelia Myrcia Rhodamnia 0 Apr 2010 Nov 2010 July 2011 Dec 2011 Aug 2012 Myrcianthes Rhodomyrtus Verticordia Date Myrrhinium Ristantia Xanthostemon Sphaerantia • Worldwide combined host list: – 450 species, 73 genera, 16 tribes Giblin F, Carnegie AJ (2014) https://www.anbg.gov.au/anpc/resources/Myrtle_Rust.html Impact on key Myrtaceae

• • Understory to small (12 m) • Highly susceptible

AVH

1 m 1 m 1

Unsprayed Sprayed Rhodamnia rubescens

• 12% of trees surveyed were dead • 2017: increase in mortality (up to 50%) • Just listed as Critically Endangered Rhodomyrtus psidioides

K. Kupsch G. Pegg Rhodomyrtus psidioides

• 50% of trees surveyed were dead • Some 100% dead • Just listed as Critically Endangered Conservation model

Start SUSCEPTIBLE

N Y

RANGE OVERLAPS?

N Y > 80 % THREATENED

< 80 % N Y

NON-PRIORITY PRIORITY CAT. C PRIORITY CAT. B PRIORITY CAT. A

Berthon et al. (under review) Biological Conservation