A new winter oilseed rape hybrid variety is clearly standing up to pressure from the fungal disease sclerotinia, as infection has taken its toll in different parts of the UK.

PT303 Protector Sclerotinia, from Pioneer – the seed brand of Corteva Agriscience – is living up to its claim to be the first variety offering growers genetic tolerance to the disease.

Near the end of the growing season, sclerotinia symptoms had been observed in a Corteva trial field near Ingatestone, Essex. In the trial, PT303 was in a 3ha block next to a different hybrid being grown commercially on the farm. The trial showcased a stark contrast in disease levels (see picture).

Corteva’s trials showed that when sclerotinia infection is at 25% or above, the severity of the disease in PT303 was reduced by up to 75%. Its seeds manager, Andy Stainthorpe, said PT303 will be a good option for farmers looking to add a layer of ‘built-in’ protection against the disease.

He said: “We are starting to see the exciting potential of PT303. We are seeing a visible lack of sclerotinia compared to a different hybrid sown in the same field. The infection seems to have taken hold, despite the whole trial field having received one fungicide at flowering time.

“This trial is a direct demonstration of PT303’s inherent sclerotinia tolerance, which could prevent a reduction in yield as high as 60%. This comparison confirms our view that the trait incorporated into PT303 is a crucial one for growers looking for consistent protection against this damaging and unpredictable disease.

“In addition, PT303 has already shown in AHDB Recommended List trials results it can deliver the highest yields and vigour, which growers will rightly be demanding to exploit the current high prices for oilseed rape. PT303 also offers proven TuYV resistance in addition to its unique sclerotinia tolerance,” he pointed out.