FARMERS need to walk their crops carefully before applying T0 sprays to ensure they match chemistry to disease threat and apply them at the right time.
“The detection last year of yet another race of yellow rust undermined the reliability of wheat resistance ratings,” pointed out BASF business manager, Ben Freer. “The only way to be sure is to get out in to crops and see what’s there.
“The winter has dampened down infections but if the disease was present earlier and has apparently disappeared, don’t be fooled. It will return.”
The T0 spray also provides a solid start to septoria control, he argued. “T0 should be applied as leaf four emerges, within three weeks and a maximum of four weeks, ahead of the T1 (GS 32) spray. If you apply it too soon, you risk stretching the T0-T1 interval, which could compromise the whole fungicide programme.”
As an approximate guide, the T0 timing usually fall from mid-April in the North of England and heading further north – but could be earlier if the weather warms up. “T0 applications are cheap insurance as they are protectant only. Expensive curative chemistry is not needed,” added Mr Freer.
He recommended chlorothalonil (CTL) at 500g/ha to provide early septoria control. “A half-rate epoxiconazole, as contained in Opus Team, or Capalo, should be added for rapid control of yellow rust and to provide additional protection against septoria,” he said.