Technical Bulletins

T0: The Ideal Starting Point for Disease Control in Cereals

Posted on 09 March 2026

Strong crop establishment last autumn and a mild winter mean many cereal crops may require early protection this season.

𝗞𝗲𝘆 𝗖𝗼𝗻𝘀𝗶𝗱𝗲𝗿𝗮𝘁𝗶𝗼𝗻𝘀 𝗳𝗼𝗿 𝗧𝟬

Early protection is crucial for safeguarding yield potential, especially in crops more vulnerable to Yellow rust.
Secondary protection against Septoria is advisable where risk is elevated.
Early rust control at T0 has consistently shown value, even in variable seasons.
T0 Yellow rust protection is particularly important for varieties with an RL score of 5 or below – Take note of significant revisions to the 2026/27 AHDB Recommended List due to the new strain of yellow rust that has broken down resistance of the Yr15 gene present in about a third of previously resistant varieties.
Assess each field’s winter condition and yield potential to tailor spray programmes.
Consider upgrading from straight triazoles to higher‑performance co‑formulations (e.g. tebuconazole + prothioconazole or spiroxamine + prothioconazole) to gain additional benefits at minimal extra cost.

Rust: The Primary Target at T0

High inoculum carryover and recent mild conditions increase the likelihood of early rust development. With several key varieties now scoring 5 or below for Yellow rust resistance, a preventative triazole‑based T0 spray remains essential for effective control of Yellow rust in wheat and Brown rust in barley (particularly hybrids).

Septoria: A Valuable Secondary Focus

Even in lower‑pressure seasons, reducing early Septoria risk helps maintain flexibility for T1 applications. This is especially relevant for earlier‑sown crops, susceptible varieties, or high‑risk areas. Folpet provides strong, cost‑effective Septoria protection.

T0 options with Clayton fungicides:

Clayton Tebucon 250EW 250g tebuconazole Disease strengths: Cost-effective rust activity
Clayton Tuskar 250g prothioconazole Disease strengths: Strongest active for stem-based diseases (e.g. Eyespot & stem-based Fusarium)
Septoria: protectant and eradicant activity*
Clayton Navaro 125g tebuconazole + 125g prothioconazole Disease strengths: Strong all-round activity
Clayton Tendril 300g spiroxamine + 160g prothioconazole Disease strengths: High performance disease control

*prothioconazole has good activity on Brown rust in barley, moderate Yellow rust activity in wheat and good protectant activity against mildew.

Additional T0 options for Clayton fungicides:

Clayton Augusta 250g azoxystrobin Disease strengths: (Rust) Rust and Take-all
Clayton Canyon SC 500g folpet Disease strengths: Strong protection against Septoria

✅ Use T0 as a cost‑effective foundation within an integrated disease management strategy.