Picking right weapon for the situation
EYESPOT control at the 225ha (556-acre) Ferme de Puisieux, just outside Laon, hinges around the level of disease infection and the weather.
Grower Francois Fontaine favours cyprodinil (Unix) when infection levels are above 20% and the weather is dry. At levels below this, or if it is wet, he will consider cheaper prochloraz (Sportak).
"In 1996 I used Unix on all our wheat varieties and ended up with yields of 10.5t/ha," he recalls. "Last year, it was very dry, and test results showed there was no need to spray for eyespot. Both products control both strains of the disease," he says. But Unix has given him the best control. "That is why it is used if there is a lot of disease."
Wheat yields average 9.5t/ha, so Mr Fontaine believes in a robust, three-spray disease control programme and spends up to £65/ha (£26/acre) keeping his crops clean.
Unix has been used since its launch. Applied at second node (GS32), its use depends on results from a free eyespot testing service operated by co-op Norepi.
"We have had a lot more rainfall this year, so I will be watching for signs of the disease very closely," says Mr Fontaine.
He has also used Unix on spring malting barley. Drilled early and treated with a two-spray fungicide programme, at first node (GS31) and flag leaf emergence (GS49), it yielded 8t/ha (3.2t/acre).
"Our main concerns with spring barley are net blotch and mildew," he points out. "Unix is good on these and we tend to mix it with epoxiconazole in both spring and winter barley."
Laon farmer Francois Fontaine favours Unix over Sportak in wet, high disease pressure years.