29 March 2002

Lower water rates to achieve improvements at T1 spraying

By Charles Abel

CEREAL growers can achieve big improvements in workrates for T1 spraying by cutting water volumes this spring.

By working with a water rate of 70 litres/ha up to 50% more output can be achieved, calculates Tom Robinson, applications specialist for fungicides supplier Syngenta.

But not all strobilurin fungicides offer that opportunity. Extensive trials using new Syngenta strob Acanto (picoxystrobin) show application at 70 litres/ha brings no loss of efficacy, says Mr Robinson. It can also be applied at forward speeds up to 16kph.

That will help boost the chances of hitting the all-important T1 application at exactly the right time, he says.

The new recommendation is based on trials in the UK, France and Switzerland last year. They used full size spraying machinery, a range of nozzle types and sizes, varying water volumes and forward speeds from 8-16kph.

For a typical 2500 litre, 24m sprayer operating at 12kph the lower water volume will boost daily work rate by 47%, he calculates. A combination of fewer fill-ups and more spraying per tank-load will lift treated area from 79 to 116ha/day.

Where a contractor is used the higher workrates could bring savings of up to £370/day, assuming, typical charges of £10/ha, says Mr Robinson.

"The new, low water volume were supporting for Acanto is particularly useful for T1, because unpredictable weather in March/April can massively cut down the number of suitable spray days and enforce spraying delays," says Mr Robinson.

He attributes Acantos suitability for low water volume application to the way it redistributes around the plant after spraying.

Tank-mix partners should not suffer either. "Following work with a range of triazole partners, we are also prepared to back their efficacy at 70 litres/ha," says Mr Robinson. "Were happy with our own range of pgrs and herbicides and there should be no problems with other tank-mix partners, although that is not something we can support ourselves."

Syngenta is already backing a 50 litre/ha water volume in France and Switzerland. Further trials will assess its potential for the UK this year. &#42

Drop water volume to 70 litres/ha to boost spray workrates by up to 50%, says application expert Tom Robinson. Youll stand more chance of hitting T1 spray windows.

Message received…

During recent judging of the Syngenta/farmers weekly Farm Sprayer Operator of the Year competition it emerged that every one of the eight finalists visited already apply all their sprays at 100 litres/ha. "The message is getting through that lower volumes help you get round the farm quicker and with faster forward speeds it is no longer necessary to use very small nozzles," says Mr Robinson.