25 August 1995

Disease threat could explode

DRY conditions are creating their own disease worries for early drilled cereals, with soil-borne bunt a particular risk this autumn.

According to Dalgety cereal seeds specialist David Neale, a return to damper conditions around drilling time could prompt an "explosion" of seed and soil-borne disease in warm soils. Fusarium, yellow rust and blue mould could all threaten establishing crops, he claims.

He urges growers to opt for a broad spectrum seed dressing, despite the additional cost of about £7.40/ha (£3/acre).

If seedbeds remain dry after drilling blue mould could be a significant threat, he reckons. In Bayer trials from 1983-90 Baytan (fuberidazole + triadimenol) gave 95.4% protection.

But ADAS disease specialist David Yarham considers blue mould a small risk. Fusarium and yellow rust should also be rare owing to low levels of inoculum.

Septoria nodorum could be a threat to coastal and fenland crops, particularly of a susceptible Soissons and Brigadier.

But a great worry is soil-borne bunt. Dry weather has persisted long enough for spores to now pose a threat to establishing crops, he says. The only protection is a systemic seed treatment, such as Baytan or Sibutol (bitertanol + fuberidazole) or Beret Gold (fludioxonil). &#42