Needle disease programmePresenters: Beccy Ganley and Carol Rolando

All people involved in project:– Nari Williams, Catherine Banham, Caro Gous, Stefan Gous, Liam Wright,

Tia Uaea, Nadine Rea, Nalini Navaranjan, Peter Scott, Ian Hood, Judy Gardner, Rebecca McDougal, Lindsay Bulman

– FOA Technical Steering Team

Acknowledgements

Programme overview

Mission: • Reduce the impact of needle diseases on New Zealand’s forests

through improved fundamental knowledge and management practices. • Build “best teams” with key researchers internationally and domestically

Outcomes:

1. Increased forest productivity by improved tree health

2. Protection of tree asset and reduced risk

3. Continued-improved market access

Needle Disease Research Programme 2013-2018

Theme 1 Predict Disease

Research Themes

Theme 2 Host

Resilience

Theme 3 Control

Activity Areas

Biotic Factors

Abiotic Factors

Surveillance

Defence

Genomics

Breeding

Augmentation

Chemical Control

ObjectivesDetermine the biological drivers

(inoculum levels, mode of infection) of pine needle diseases

Determine abiotic drivers (weather, nutrition, silviculture) of

pine needle diseases

Identify risk factors (threats, climate change), develop tools (prediction, remote sensing)

Breed for resilient, disease-resistant, healthy forests

Use genomic tools to elucidate targets for increased host

resilienceDetermine the role of host,

biological and environmental factors in host defence

Develop cost-effective chemical control strategies for key foliar

pathogensManipulation of factors (stand management, landscape) to

reduce disease

Benefits/OutcomesImproved control and reduced

application cost, markets maintained

Reduced chemical control costs

Protection of forests enhanced by improved readiness

Increased growth, reduced vulnerability to diseases

Enhanced host resilience to pine needle diseases, including new

diseases.

Increased host defence, biological control, improved growth

Reduced incidence of foliar pathogens

Improved productivity and low cost control

Red needle cast/Phytophthora pluvialis

• First reports of new disease in 2008• Identified new-to-science Phytophthora species

• Only isolated P. pluvialis from needles

• Attempts to artificially colonise material other than needles have been unsuccessful

• Rapid decline in spore survival on log surfaces

Possibility of transmitting P. pluvialis from New Zealand on radiata pine logs is negligible

Impact and risk assessments

• Understand how and when inoculum is released and when disease occurs

Outcome•Results are critical for effectively controlling and managing red needle cast

Benefit•Improved control and reduced application cost•Increased productivity

Objective

Monitoring

Monitoring

• Relationship between zoospore release, infection timing and symptom development

• Relate disease to seasonal weather factors• Field scoring versus image processing

Bait bucketsDisease expression Potted cuttings Digital images Weather data

* PK isolated from nearby foliage

Disease expression and timing

Winfolia analysis

• When the disease is occurring

• Timing between disease expression and defoliation

Correlate with weather data

Take photos through the

year

Disease risk maps

Cyclaneusma needle cast

Two morphotypes of Cyclaneusma minus • ‘simile’ and ‘verum’

What is the prevalence of both morphotypes?Do both morphotypes cause disease?

The morphotype ‘simile’ was the most prevalent and had the greatest geographical distribution

Developing primers to distinguish the two morphotypes

? ?

• Develop a cost effective chemical control treatment for red needle cast.

Outcome•Industry has chemical control strategy to manage red needle cast in existing stands of radiata pine

Benefit•Increased productivity•Protection of stands at risk

Objective

Approach

• Identify causal agent and develop assays for testing efficacy.

• Using controlled studies, determine efficacy and persistence of:

– phosphite– alternative chemicals

• Use controlled and field dose response trials with most promising chemicals to identify optimum treatment.

• Cost-benefit analyses to guide application strategy.

• Use spray technology to optimise application volume and brew.

Integrate all chemical control information with epidemiology, monitoring and modelling to determine when it is necessary and beneficial to spray with optimum brew.

Optimised uptake of phosphite

• Adjuvants improve uptake of phosphite, DuWett at 0.2% increased uptake by 9-fold

• Uptake proceeds for up to 72 hours after application

Outcomes …

• Demonstrated efficacy and persistence of phosphite for P. pluvialis on P. radiata

– Needles sampled from trees injected with phosphite at 1 g a.i. cm-1 dbh had consistently smaller lesions than needles sampled from control trees one year after injection.

– High volume, foliar application of 2% phosphite significantly reduced lesions formed by P. pluvialis for up to eight months after application.

Outcomes …

Persistence of stem injected phosphite

July

October February

Persistence of high volume foliar applied phosphite

• Alternatives to phosphite show potential for control of RNC

– Three months after application AGPRO Copper Oxychloride 800 WP®

and Ridomil® Gold SL showed efficacy against P. pluvialis.

– The efficacy of the active ingredients was dependent on host susceptibility to the pathogen, with higher rates of chemicals required to reduce lesion development in the susceptible clone.

Progress …

Product Active Ingredient Group ModeEstimated cost ($ ha-1)

Agrifos®600

 

600 g L-1 phosphorous acid

phosphonate systemic $150.00

AGPRO Copper Oxychloride 800 WP

 

500 g L-1 copper oxychloride

inorganic copper

protectant $30.00

Ridomil® Gold SL

 

480 g L-1 metalaxyl-M phenylamide systemic $135.00

Fungicides tested in pot trial with two clones

• Agrifos®600 applied at 20 L ha-1 at a cost of $7.50 per litre• Copper Oxychloride 800 WP applied at 3 kg ha-1 at a cost of $10 per kg• Ridomil® Gold SL applied at 3 L ha-1 at a cost of $45 per litre

Lesi

on le

ngth

6 d0

10

20

30

90 d

control0.75 kg

1.50 kg3.00 kg

Efficacy of copper oxychloride applied in the equivalent of 100 L per hectare

at 0, 0.75 kg, 1.5 kg and 3 kg per ha active ingredient

Next steps (2014-2015)

• Examine effects of concentration and dose on uptake of phosphite (PPCNZ).

• Determine the effects of phosphite concentration on droplet spectra using two different nozzles.

• Conduct field and controlled dose response trials to determine efficacy and persistence of phosphite.

• Re-test efficacy and persistence of copper applied as the Dothi Standard

• Complete a cost:benefit analysis on phosphite application to control RNC.

www.research.nzfoa.comwww.scionresearch.com

Beccy Ganley and Carol Rolando

Beccy.Ganley@scionresearch.comCarol.Rolando@scionresearch.com

Date: 29 October 2014