19 August 1997

Rhizomania and brown rot threat to eastern counties

NEW outbreaks of two root crop diseases are threatening the livelihoods of growers in the eastern counties.

The sugar beet disease rhizomania has been confirmed in Notts and brown rot, which attacks potatoes, in Bedfordshire.

The rhizomania outbreak, the first outside Norfolk and Suffolk, could damage prospects for maintaining the UKs rhizo-free status, warned experts.

A further seven outbreaks have been confirmed on new farms in Norfolk and Suffolk, and 13 more fields on already infected holdings.

Mike Asher of the Institute of Arable Crops Research at Brooms Barn is not surprised to see the disease spread to a new area. "The latest outbreak is on a light sandy soil where we would expect the disease to show. It continues the gradual progression of the disease as seen abroad."

The Notts outbreak is likely to mean the end of the UKs rhizomania protection policy which is due for discussion in 1999. "The EU is going to look long and hard now we have failed to contain the disease in Norfolk and Suffolk," said Steve Ashby of the MAFFs Plant Health Division, York.

If the protection policy ends, MAFF powers of containment, which include prohibiting the growing of beet on infected fields, will disappear.

Brown rot has been confirmed in two separate tomato glass houses in Beds, writes Charles Abel.

Infection is believed to have come from irrigation water taken from the River Ouse raising fears about possible contamination of irrigated potato crops.

MAFFs Brian Ellam said: "If its brown rot in the water then its likely to be further down the watercourse too." But he added that infected tomatoes were not thought to pose a risk of transmission and that no waste water from the tomato units is believed to have been returned to the river. Also potatoes grown in fields are at less risk than glasshouse tomatoes.

Speaking at Potato Harvest 97, David Walker, chairman of the British Potato Council, said: "While the outbreaks are serious, I dont think we should overstate the risk to potato crops alongside the river."

Growers should check stored potato crops and notify MAFF if they find vascular browning leading to weeping eyes. &#42