To stay ahead in a landscape shaped by environmental regulation, emerging pests, and shifting consumer demands, Potatoes New Zealand continues to invest in a robust Research, Development and Extension programme. Focused on supporting growers by reducing production challenges, increasing yields, and ensuring the sector remains competitive as well as sustainable, Potatoes New Zealand’s current Research and Development activity spans six core priorities.
What follows is an overview of the current and potential projects aligned with these priorities:
- Powdery Scab Management
- Tomato Potato Psyllid / Liberibacter Control
- Potato Tuber Moth Management
- Early Blight Control
- Nitrogen Management – Sustainable Vegetable Systems
- Common Scab (Literature Review and Extension)
1. Powdery Scab Management
Powdery scab, caused by Spongospora subterranea, is a persistent challenge, with spores that can remain viable in soil for over a decade.
Lead Researcher: Prof. Calum Wilson, University of Tasmania
Two major approaches are currently under evaluation:
Diffuse to Confuse
One field trial, recently harvested and pending final reporting, assessed five treatments designed to disrupt zoospore migration, a critical step in the infection process. These compounds work by “confusing” the zoospores, preventing them from locating their potato host roots, and in some cases, killing them before infection.
Germinate to Exterminate
A long-term trial is about to start and will use copper gluconate to stimulate premature germination of resting spores in the absence of a host. Since germinated spores cannot survive without a plant, this method could dramatically reduce the pathogen’s presence in soil over time. The trial is set to take place over a three-year period at a location with a longstanding incidence of severe Powdery Scab.
Next Steps: Pending Technical Panel approval
Future research to be determined may also explore the use of soil nutrients like Manganese (Mn), Zinc (Zn), and Boron (B) as well as soil microflora to enhance resistance or suppress pathogen development.
2. Tomato Potato Psyllid (TPP) / Liberibacter Control
The Canterbury Potato Liberibacter Initiative (CPLI), established and funded by a committee of Canterbury growers and processors, with additional financial support from Potatoes New Zealand, is pioneering work to manage TPP and Candidatus Liberibacter solanacearum and it is scheduled to conclude this year, however several critical projects will be continuing:
- Calcium Propionate Trial
Lincoln University is assessing the efficacy of calcium propionate (a food preservative), applied via seed and/or foliar, in reducing Candidatus Liberibacter solanacearum infection or psyllid activity. Trials are still underway. - Longevity of different insecticides on potato crops
These trials focus on determining how long various insecticides can be detected within the plant following a spray application. The next step will be to investigate how long these residues remain effective in controlling psyllid populations.
- Psyllid Suction trapping and gut content analysis
There’s a need to know the feeding source of psyllid during winter. The idea is to collect psyllids through suction traps/ sweep netting and analyse the gut content to determine where they have been over-wintering.
- Integrated Pest Management (IPM) in potatoes
There’s a proposal to set up a commercial production site in Canterbury using a strict Integrated Pest Management approach with the aim of achieving comprehensive pest management without relying solely on pesticides.
3. Potato Tuber Moth Management
The Pukekohe region continues to experience high pressure from Potato Tuber Moth (PTM), exacerbated by soil cracking, warm/humid climates, pesticide resistance, and ambient storage conditions.
Key Activities
Monitoring Network: An expanded PTM trapping program includes deployment of smart traps that enable real-time monitoring, data collection and distribution of results. Comparative analysis is planned to be conducted against traditional pheromone traps.
Post-Maturity Management
Trials will examine various soil moulding techniques post-crop maturity to assess efficacy in minimising tuber exposure and subsequent infestation.
4. Early Blight Control
BioScout Spore Detection Technology is under consideration to enable early warning and targeted fungicide application. The system comprises an autonomous spore trap and a real-time dashboard for fungal disease monitoring. It identifies airborne spore presence prior to symptom expression, supporting precision spray decisions and reducing unnecessary inputs.
A proposal is being developed to explore the impact of chitosan, a naturally derived biopolymer, on disease suppression, plant vigour, and tuber quality.
5. Nitrogen Management – Sustainable Vegetable Systems (SVS)
The SVS tool (www.svstool.co.nz), developed collaboratively by industry stakeholders, supports growers in meeting environmental standards while maintaining productivity.
Some of the benefits of the SVS tool include:
- Informed nitrogen management decisions
- Reduced nutrient loss and leaching
- Compliance with regional freshwater regulations
- Enhanced agronomic and economic performance
Next Phase:
Ongoing maintenance, industry engagement, and education initiatives are planned to ensure wide adoption and integration of the SVS platform.
6. Common Scab (Streptomyces spp.)
A comprehensive literature review is in progress, in response to rising concern about common scab. This will summarise over 50 years of global research, with an emphasis on:
- Crop rotation strategies
- Soil and seed treatment options (biological and chemical)
- Practical, regionally applicable recommendations for New Zealand growers
Looking Ahead: A Future Driven by Innovation
As the industry faces increasing pressures from climate change, cost volatility, shifting consumer expectations, and evolving environmental regulations, innovation is more critical than ever. Potatoes New Zealand’s research and development strategy will be shaped to reflect these realities, with science-led, grower driven research, technology, and new ideas. This will include investigating alternative products, value-added opportunities, and precision tools that will support growers to adapt and thrive in a changing landscape.
Potatoes New Zealand remains committed to delivering high-impact research and practical tools for growers, processors, and the wider industry. Through a strong research and development agenda, Potatoes New Zealand’s goal is to:
- Strengthen and enhance pest and disease management
- Improve resource use and input efficiency
- Unlock market opportunities through value-add and alternative products
- Equip the industry to adapt to environmental and economic pressures
- Foster long-term resilience, sustainability, and global competitiveness
The future of potato growing will be shaped by our ability to think ahead, adapt quickly, and work collectively. Potatoes New Zealand’s investment in science-led, grower-informed innovation is central to that vision – for today and tomorrow.