31 May 2002

Industry learns

to live with rhizomania

NEARLY all the UKs rhizomania-blighted land could be back in sugar beet next year, easing rotational problems for growers affected by the disease.

Before then a well-advertised factory intake period for infected crops, involving extra hygiene measures, will be introduced, growers heard at an Advanta Seeds conference last week.

Allowed back

BSs John Prince confirmed that almost all 7000ha (17,300 acres) barred from growing sugar beet under the UKs former Protected Zone status would be allowed back into production.

"But tolerant varieties must be grown," he stressed. "It is important to minimise the build up and spread of this disease in the UK." Rhizomania affects only about 1% of the UKs beet growing area. In Holland resistant varieties are required on about 80% of the area.

Only on two farms in Norfolk, where the new Pithivier strain of the virus has been found, will freedom to sow be restricted.

The chance to grow beet on infected land again won praise from grower Robert Gooderham. "It is very welcome. It gives me more flexibility." A quarter of his beet land near Thetford, Norfolk has been rhizo-hit.

Many in the industry had hoped the UKs Protected Zone status would stay for another two years. "But that two years of comfort was denied us," said the NFUs Lindsay Hargreaves. "So we had to come up with something that balanced the needs of everyone.

"For a lot of growers rhizomania is not much of an issue. But others, whose rotations have been completely shattered, have been crying out for change."

Crops affected by the more common A and B strains will be allowed into growers contracted factories, albeit during a period yet to be finalised. "It will probably be a week in early December," said Mr Prince. "We will advertise it so all growers will know that rhizo beet is being harvested and delivered then."

Crop surveying and virus typing would continue, partly with CSL help and DEFRA funding. Much more needed to be known about the p-strain, similar but not identical to that found in France, delegates heard. China and Japan are the only other countries where it occurs.

Mike Asher of Brooms Barn said there was evidence that it may be eroding the value of resistant varieties in France. "We need to know how pathogenic it is and whether it is really as aggressive as the French claim it to be." &#42

2003 SOWING ADVICE

With rhizomania potentially costing growers up to £54/ha (£22/acre) in terms of lower yield compared with best susceptible types on healthy land, extra seed costs and maybe more rust control, BS advice on 2003 sowings is:

&#8226 Resistant varieties vital for infected land.

&#8226 At risk fields need threat assessment.

&#8226 Elsewhere stick to susceptible varieties – seed is cheaper.

2003 SOWING ADVICE

With rhizomania potentially costing growers up to £54/ha (£22/acre) in terms of lower yield compared with best susceptible types on healthy land, extra seed costs and maybe more rust control, BS advice on 2003 sowings is:

&#8226 Resistant varieties vital for infected land.

&#8226 At risk fields need threat assessment.

&#8226 Elsewhere stick to susceptible varieties – seed is cheaper.