Verticillium wilt, confirmed in UK oilseed rape last year for the first time, is adding to the problems of premature ripening caused by sclerotinia in this season's stands, warns ADAS.

Growers are advised to check crops now for the symptoms.

These typically consist of a dark brown stripe running up one side of the main stem. Closer inspection may reveal grey micro-sclerotia as the surface layers start to decay.

The wilt disease is becoming more widely recognised as awareness of the symptoms has grown, according to the service's Crop Action notes.

It can be detected at 0.1% of plants affected in some crops. But badly affected fields may have more than half the plants hit with either whole plants or just side branches ripening prematurely.

On farms where verticillium is obvious growers are urged to extend rotations to at least one in four and longer if possible where the infection is severe.