Strong case for a T0 treatment in wheat
There is a very strong case for a T0 treatment in wheat this year, according ProCam UK Agronomy Manager, Nick Myers.
"We are already flagging up disease in wheat - Septoria is very evident on older leaves across the country and even some mildew in forward crops, despite the cold December," Nick reports.
"We have also found yellow rust on Robigus and Oakley, not at severe levels as yet, but it is there."
There are two types of wheat crops this year, he says. The early sown crops, drilled in September got a great start, survived the winter and are well tillered and quite lush now. These crops have attracted higher levels of disease than we would normally expect to see at this time.
Then there are the crops, mostly second wheats, drilled later in October that aren’t as forward.
"Normally the prime timing for Septoria control is T1, around GS 31 to 32, but there is a definite need to damp down the disease inoculum earlier than that.
"This is where a T0 spray comes in and why it is a particularly important timing this year. Disease is there, crops are at risk and the value of the crop is so much higher this year."
The ProCam 4cast agronomy database has, over a number of years, shown a consistent yield benefit of 0.54 t/ha from a T0 treatment, Nick says.
"This is a fantastic economic response, valued at £108/tonne with feed wheat at around £200/tonne. With a potentially high value for the crop, it is important to look after the crop from Day 1. A well-timed T0 treatment is an essential starting point to protect the crops’ potential."
Nick advises that T0 sprays are applied between GS 25-30, normally around the end of March, with the T1 spray applied three to four weeks later. This year T0 could be earlier, as some crops are already at mid-tillering, he says.
"A good triazole plus a good protectant such as chlorothalonil is the base treatment for T0, but then add in whatever else might be needed, considering disease risk and the variety grown. If growing a rust-susceptible wheat, a rust-specific component such as cyproconazole can be added in.
"If mildew is a threat, add in a specific mildewicide such as a morpholine or cyflufenamid. If eyespot is a threat, for example in second wheats, then add in an eyespot specific component such as prochloraz."
It is more important than ever to keep the crop standing so there will be a significant emphasis on PGRs this year, Nick Myers adds.
"Most crops are advanced and will need a strong growth regulation programme.
"However, there are some backward crops too and these will need special attention to improve tillering and promote crown root development. These backward crops will benefit from phosphite or a zinc ammonium acetate growth promoter at mid-tillering/GS30 with the first PGR.
