Trial shows value of T0 sprays across several different seasons
© Tim Scrivener A well-planned T0 spray may prove to be a cost-effective insurance policy this spring, especially given that early drilling, high crop biomass and a mild winter have created what experts describe as a potential “perfect disease storm”.
The benefits of a well planned T0 have been demonstrated in Agrii trials conducted over several years, with yield responses ranging from 0.15–1.1t/ha.
See also: Yellow rust resistance blamed on dominant wheat varieties
This is equivalent to £24-£176/ha at £160/t, with an average uplift of 0.41t/ha, explains Jodie Littleford, technical manager for combinable crop trials at Agrii.
“In yellow rust situations specifically, the average benefit of a T0 over the past three years has been +0.65t/ha – worth around £104/ha at £160/t,” says Jodie.
“For a modest upfront cost, it’s an affordable way to safeguard yield potential rather than chasing disease later.”
A mixed azole approach remains one of the most cost-effective T0 strategies, adds Ruth Stanley, commercial agro manager (UK & Ireland) for Sumitomo Chemical.
Using mixtures such as Sakura (bromuconazole + tebuconazole) provides broad-spectrum protection while supporting resistance management, she says.
This has been confirmed by Agrii trials in Scotland, which showed this mix outperformed straight azole options by 0.47 t/ha.
“A well-timed T0, integrated within a multi-mode-of-action programme, enhances the reliability and performance of subsequent T1 and T2 applications.
“We have found a multisite-inclusive programme delivered a 0.53t/ha benefit compared with T1 and T2 alone.”
Jodie adds that using a mixed azole at T0 also frees up strobilurin applications for later in the programme.
“With reduced SDHI sensitivity in brown rust and the possibility of heightened rust pressure in a mild season, retaining flexibility later could be crucial.”
She also notes that including a biostimulant, such as Innocul8, may provide additional plant health benefits as part of a robust early-season strategy.
A high pressure season?
Sumitomo’s Ruth Stanley warns that many crops are already carrying significant disease pressure following well-established autumn drilling.
“Large areas of wheat were drilled from mid-September through early October, so crops are forward and carrying substantial biomass,” she explains.
“With no prolonged cold spell over winter, diseases such as yellow and brown rust have continued to develop.
“Add to that more second wheats and extremely wet conditions, and the risk from stem-based diseases such as take-all and eyespot increases.”
New for 2026
This is the first season for the co-formulation of Bayer’s latest SDHI and Corteva’s Inatreq active.
Last autumn, Bayer secured approval for Jessico Fusion, which contains the company’s Iblon (isoflucypram) and the Inatreq active (fenpicoxamid).
Greg Hanna, fungicide market development for Bayer says the fungicide has demonstrated excellent efficacy against septoria, yellow rust and brown rust.
He says the active substances combine to deliver an excellent broad spectrum disease control make it well-suited to T2, but with the flexibility to be used at T1 in higher septoria pressure conditions.
The chemicals regulation division (CRD) of the Health and Safety Executive also lifted restrictions on the use of Iblon (isoflucypram), enabling its use in second wheats.
Farmers had been restricted to a maximum of 75g/ha of the active every two years in the same field.
At the minimum supported dose of 50g/ha active substance, this effectively limited its use to one application every two years.
The CRD also granted a label extension allowing Vimoy (Iblon) to be used on barley crops for the first time this spring.
