Needle disease programme Presenters: 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 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 Objectives Determine 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 resilience Determine the role of host, biological and environmental factors in host defence Develop cost-effective chemical control strategies for key foliar pathogens Manipulation of factors (stand management, landscape) to reduce disease Benefits/Outcomes Improved 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

Relationship between zoospore release, infection timing and symptom development Relate disease to seasonal weather factors Field scoring versus image processing Bait buckets Disease expression Potted cuttings Digital images Weather data

Feb23-Feb 1-Mar8-Mar 15-Mar22-Mar 16-Apr23-Apr30-Apr 7-May 14-May21-May 4-Jun 18-Jun 5-Jul 19-Jul 3-Aug 17-Aug31-Aug 5-Sep 27-Sep 12-Oct26-Oct 7-Nov 30-Nov 14-Dec27-Dec Maxwell’s Road N/ A --PP PP + Pk N/ A - PP + PK PP PP + PK ---- Puninga Road N/ A ----PP N/ A -PP ---- Paritu Road N/ A ----PK--PP N/ A -PP Tikitere -----PK Kapenga -----PP Jan 8-Feb 22-Feb 8-Mar 14-Mar21-Mar 5-Apr9-Apr 18-Apr 2-May 16-May30-May 7-Jun 13-Jun27-Jun 1-Jul 26-Jul 8-Aug 23-Aug30-Aug 5-Sep 13-Sep25-Sep 11-Oct24-Oct 6-Nov 14 Nov21 Nov29 Nov 10 Dec19 Dec Maxwell’s Road -----PK PP PP + PK PP--- PP + PK PP Puninga Road PP- Paritu Road PKPP - - Tikitere Kapenga Jan 5-Feb 20-Feb 6-Mar 19-Mar 3-Apr 24-Apr 2-May 15-May29-May 13-Jun26-Jun 10-Jul23-Jul 13-Aug28-Aug 11-Sep17-Sep30-Sep 15-Oct Maxwell’s Road PP---- Puninga Road PP--- Paritu Road -----PP- - Tikitere PK Kapenga * * 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 ‘simile’ ‘verum’ 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 …

ProductActive IngredientGroupMode Estimated cost ($ ha -1 ) Agrifos® g L -1 phosphorous acid phosphonatesystemic$ AGPRO Copper Oxychloride 800 WP 500 g L -1 copper oxychloride inorganic copper protectant$30.00 Ridomil® Gold SL 480 g L -1 metalaxyl-Mphenylamidesystemic$ 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

Lesion length 90 d control 0.75 kg 1.50 kg 3.00 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 ( ) Examine effects of concentration and dose on uptake of phosphite (PPC NZ ). 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.

Beccy Ganley and Carol Rolando Date: 29 October 2014