5 September 1997

Rhizo explosion falters

RHIZOMANIA is proving tougher to find than expected this season, with just 13 newly infected sugar beet fields confirmed so far.

All but one is on a farm already contaminated with the disease.

"Given the warm spring we were convinced there would be a lot of new outbreaks this year," said Mike Asher of IACR Brooms Barn, Suffolk. "In Holland and France rhizomania appeared earlier than ever and on our two UK trial fields symptoms were already evident in early July."

He added that aerial photo-graphs were now failing to show the tell-tale yellow patches in crops which denote suspected outbreaks. "Widespread yellowing is making such areas hard to find this season."

The only new outbreak identified so far was in an existing East Anglian rhizomania zone. "It is early days yet. The next week will show what is really happening," Dr Asher said.

Only a huge number of new outbreaks would jeopardise the UKs rhizo-free status, which is set to remain until renegotiation in 1999, he said. That means vegetable imports, including seed and ware potatoes, will remain subject to inspections and must come from rhizo-free areas. &#42