A project with the potential to benefit multiple sectors by finding a long term solution to bacterial diseases will move forward to on-plant testing on three crops.
The first year of the project, which investigated potential controls for bacterial diseases, has identified several organic compounds showing promising results. Testing on plant will now be undertaken in two perennial crops – cherry and kiwifruit – and one annual crop – tomato.
The work by Waikato University and Bioeconomy Science Institute, Plant & Food Research group, and funded by all A Lighter Touch (ALT) product group partners, is an extension of initial work by Zespri which identified some compounds derived from marine algae and some commercially available compounds that are able to inhibit the kiwifruit bacterial disease Psa.
Bacterial diseases in horticulture pose a significant threat, causing substantial yield losses, economic damage, and impacting crop production due mostly to a lack of control options. In the case of kiwifruit, the bacterial pathogen Psa threatened the future of the entire industry.
Kiwifruit is one of the crops to be used in the on-plant testing. Credit: Zespri
Current control methods rely on antibiotics and copper, which are not sustainable long-term, and resistance development is an ever-present threat.
Six of the most efficacious organic compounds will be tested in model plant systems for phytotoxicity and for efficacy against the relevant Pseudomonas pathogen for each plant system.
These three crops and their respective pathogens have been selected for their representative nature, commercial relevance and practicality (ease of growth, budgetary and time constraints). They also serve as models for other annual and perennial crops.
The aim of these on-plant tests is to identify a compound or compounds that could be advanced to field trials.
A Central Otago cherry orchard affected by the bacterial disease Pseudomonas syringae pv. Morsprunorum, a disease for which new management options are being sought. Credit: Bioeconomy Science Institute, Plant & Food Research group.
Long term, this could lead to new bacterial disease management options, reducing the current reliance on copper and antibiotic treatments within plant-based food sectors and provide more environmentally friendly and sustainable control options.
This project also aligns with A Lighter Touch’s goals of enabling collaboration on pan-sector issues, working together and faster to find new crop protection tools. The 17-month project is due for completion in December 2026.
Keep up to date with this project here.
