Consider application technique with T2 fungicide

Paying attention to spraying technique with a T2 fungicide could help growers better protect the yield potential of this year’s winter wheat crops, says a leading application specialist. An important point, he says, could be to make the most of available spray windows to ensure crops are protected on time.

According to Syngenta application specialist Tom Robinson, being just a day late with a T2 fungicide can mean crops lose 0.07 t/ha in yield – or nearly 0.5 t/ha if spraying is delayed by a week.

“The T2 fungicide is designed to protect the important uppermost leaves, the flag leaf and leaf 2, but also to top-up disease control on leaves just below,” says Mr Robinson, “which also contribute to yield.

“Even in fields where crop potential is reduced this season, for example because they were drilled late, it’s still worth looking to maximise whatever potential they do have.

“Following their high yield results, SDHI fungicides are likely to form the backbone of T2 disease control in many winter wheat crops this season. So to help growers get the best from our SDHI fungicide isopyrazam (IZM), which is in the product Seguris, we have conducted trial work looking specifically at its performance with different application techniques to help growers protect more hectares on time.

“In the trial we found IZM worked well when applied in a 100 l/ha water volume, as well as through Amistar Nozzles designed to reduce drift and at a 16 kilometre per hour sprayer speed. All of these can help to improve spraying efficiency.”

In response, Mr Robinson suggests that growers consider these in a three-point plan:

1. Water volume

Spraying in a 100 l/ha rather than 200 l/ha water volume can allow 30% more hectares to be treated per day, and therefore potentially on time, calculates Mr Robinson. Usefully, he says testing of IZM in a 100 l/ha water volume has shown it worked fine.

2. Nozzles to reduce drift

Using nozzles that reduce drift can open up more spraying days, says Mr Robinson. He adds that Amistar Nozzles, which have been designed to reduce drift, can potentially open up four more spray days in May and four more in June – both of which are months when T2 fungicides could be applied this season. Importantly, IZM has been shown to give good spray deposition on flag leaves and other upper yield-building leaves through Amistar Nozzles, he says.

3. Sprayer speed

In suitable conditions, spraying at 16 kilometres per hour, rather than a more typical 12 kilometres per hour, can achieve around a 15% increase in the number of hectares treated per day, calculates Mr Robinson.

A specially-developed Go Faster version of the Amistar Nozzle, which has a larger 035 orifice, has also been tested with IZM, he points out. “In the trial, an extra 0.3 t/ha was produced compared to traditional fan jet applications when applying IZM through the Go Faster Amistar Nozzle at 16 km/hr and at a 100 l/ha water volume,” he says.