Rising Pest and Disease Pressures: Implications for UK Arable Farming

Climate-Driven Pest Increases

Greater numbers of pests, particularly aphids, are being observed across UK arable fields. This increase is largely driven by early-season warmth, sunshine, and previously mild winters. The lack of frost has disrupted the traditional boom-and-bust cycle, resulting in a continuous rise in aphid populations. Climate change is expected to exacerbate this trend, leading to more frequent aphid population booms.

Monitoring and Survey Insights

Week commencing 02/06/25, the Rothamsted Insect Survey of the rose-grain aphid (Metopolophium dirhodum) showed a slight increase over the previous week. This highlights the importance of in-field monitoring to stay ahead of pest pressures and make informed management decisions.

Yellow Rust in Wheat

The Yr15 resistance gene for Yellow Rust has failed, making previously resistant wheat varieties vulnerable. Varieties such as Beowulf and Champion appear to rely on the single Yr15 gene, while Arnie and Vibe show stacked tolerance through multiple resistance genes. New Yellow Rust strains under investigation appear more aggressive and widespread than before, increasing the urgency for vigilant monitoring and strategic variety selection.

Tebuconazole Availability

Tebuconazole, a key fungicide for disease control, faces uncertain long-term availability in the UK. Based on the situation in Europe, the UK could lose access to this fungicide in three to four years, with its renewal scheduled for August 2025. This potential loss necessitates the exploration of alternative disease control strategies.

Practical Actions for Growers

• Reaffirm variety choices—Crusoe and Palladium do not rely on the Yr15 gene.
• Select varieties with multiple resistance genes to enhance resilience.
• Remain vigilant and continue in-field monitoring for pests and diseases.
• Do not rely solely on AHDB Recommended List disease ratings.
• Note: Future resistance scores will be based on one-year ratings rather than five-year averages.

These insights underscore the need for proactive management and adaptation in the face of evolving pest and disease pressures.

To hear more on this topic, tune into our June Agronomy Club Recording.