Tom Harrison, a fourth-generation farmer from Norfolk, manages 1,200 hectares of mixed crops across a mix of rented and owned land, with 460 hectares dedicated to potatoes. Facing rising challenges from Potato Cyst Nematode (PCN), a pest capable of reducing yields by up to 80%, Tom wanted to develop a comprehensive integrated pest management (IPM) strategy to tackle the problem sustainably and try non-chemical approaches where possible.
Tackling persistent PCN pressure
PCN infestation, caused primarily by Globodera rostochiensis and Globodera pallida, was affecting crop yields across several fields.
Given the pest’s ability to survive in the soil for over 20 years, Tom needed a solution that would manage PCN populations effectively while maintaining soil health and yield consistency.
Developing a comprehensive PCN management strategy
1. Precision soil sampling for PCN
- Tom’s first step involved regular and thorough soil sampling across all potato-growing fields. This allowed for accurate detection of PCN presence, pressure and species identification. This helped Tom make data-driven decisions about which control measures to apply in specific areas.
- 2. Selecting nematode resistant potato varieties
- Based on soil test results, Tom tailored his potato variety choices:
In low PCN reading fields: he selected high-yielding varieties with minimal PCN resistance to maximise production without promoting resistance buildup.
In high PCN reading fields: varieties such as Amanda and Elland were used for their strong resistance and tolerance, thereby reducing nematode reproduction and yield loss.
3. Biofumigation with mustard crops for PCN control
Tom incorporated biofumigation into his crop rotation strategy by planting hot mustard blends (Brassica juncea). When incorporated into the soil during the flowering stage, these crops release natural compounds that are toxic to PCN, helping to reduce nematode numbers biologically.
4. Trap cropping using Solanum sisymbriifolium
In heavily infested fields, Tom experimented with trap cropping using Solanum sisymbriifolium, a plant that triggers nematode hatching without allowing reproduction, effectively lowering PCN populations in preparation for future potato planting.
5. Targeted nematicide application
For areas with the highest PCN levels, Tom used granular nematicide, Nemathorin applying it strategically and responsibly at planting time to reduce populations when potatoes are most vulnerable. The product was used under strict application guidelines to ensure environmental safety and crop protection.
Impact on PCN from the IPM programme
This integrated strategy produced notable results:
Reduced PCN counts across the farm, as confirmed by follow-up soil sampling
Improved yields in fields previously affected by PCN
Enhanced soil health due to biofumigation and crop rotation practices
Reduced reliance on nematicides, lowering input costs
Lessons learned
Tom’s strategy was built using the help of several experts, including independent agronomist Simon Alexander, Alistair Neill from Prime Agriculture and Alastair Ross from Frontier Agriculture.
The strategy offers a valuable model for other potato growers facing similar PCN challenges, highlighting the importance of integrating biological, cultural, and chemical tools responsibly, where needed, in a robust pest management programme.
