24 May 2002

Right T3 nozzle can add up to 0.5t/ha

By Charles Abel

MORE effective control of cereal ear diseases could be achieved by changing nozzle set-up for T3 sprays.

"The problem with the standard downward facing nozzle is that most of the fungicide ends up on the side of the ear facing the sprayer," says Syngenta applications specialist Tom Robisnon.

Now a £100,000-plus project with Lurmark and Silsoe Research Institute has developed a T3 nozzle to enhance ear coverage.

Separate trials by Bayer suggest yield responses can be significant. Using 8001 flat fan nozzles angled forwards and backwards can dramatically improve spray coverage, halving fusarium infection in field trials and boosting T3 fungicide responses by up to 0.5t/ha, says the firms Richard Elliott.

But the two nozzle approach means very small nozzle openings. That can lead to big drift problems, particularly at the faster forward speeds and lower water volumes growers now use to speed workrate, warns Mr Robinson.

The Amistar Nozzle, based on a single 10í backward facing air induction nozzle, is Syngentas solution. Designed for use at 12kph and 100 litre/ha water volume it consistently gave the best spray coverage in wind tunnel tests, without risking drift.

Over 800 free sets are available from Syngenta this season. "If it does well we will look at offering it around the world, with a view to making it a commercial product," Mr Robinson concludes. &#42

&#8226 Good coverage vital.

&#8226 Forward + backward facing nozzles effective, but risk drift.

&#8226 "Amistar Nozzle" suits fast, low volume work.

&#8226 Free from Syngenta.