22 March 2002

Solution for gout fly pest

SEVERE gout fly damage in early-drilled cereals could have been significantly reduced by an October pyrethroid spray, judging by observations from the Scott Abbot Arable Crops Station at Thornhaugh near Peterborough, Cambs.

Savannah winter wheat drilled on Sept 12 has been hit hard on the limestone brash site, 60% of plants being affected, says trials manager Nick Burton.

But Claire drilled on Sept 5/6 has less than 5% damage. "The only difference seems to have been that the early-drilled crop had an anti-BYDV pyrethroid spray included with Crystal herbicide at the peri-emergence/one true leaf growth stage."

Mr Burton believes that was enough to prevent adult gout flies feeding and laying eggs during the mild October conditions.

The struggling crop had not lost tillers last week, but Mr Burton fears more than just the main tillers are at risk. "The ability of crops to recover is directly related to their nitrogen uptake, so we applied 40kg/ha on Mar 8."

For more details see farm diary at www.SAACS.org.uk &#42