17 May 2002

At least one-third dose for ear wash

FUSARIUM is well controlled by an ear spray of Caramba (metconazole) or Folicur (tebuconazole), says Dr Jenkinson.

But because other fungi may be present it is best to widen the spectrum by adding Amistar (azoxystrobin), which controls M nivale but not fusarium species.

"You need to use at least one-third rates of these fungicides. Anything less and you are gambling," he warns. "The best timing is before or after a thunder shower during full ear emergence or anthesis."

Jo Sykes of BASF backs that view. One-third dose – 0.5 litres/ha in Carambas case – is quite low for controlling mycotoxins, and 0.75 litres/ha would reduce them much more effectively, she says.

Although not on its label, Caramba also controls glume blotch and suppresses sooty mould and mildew, she notes.

"Most quality wheat growers will consider a T3 spray," says Dr Sykes. Last year 53% of Malacca received such a treatment.

"We would not recommend a straight strobilurin because although giving a nice bright ear, it will not completely control fusarium ear blight." &#42