An aggressive strain of disease is a major threat to the United Kingdom's potato industry, a leading researcher has warned.The seed-borne disease, now renamed dickeya solani and closely related to traditional blackleg, causes soft rots and severe damage to tubers.
It has also spread rapidly across Europe in just seven years since it was first identified in eastern Poland in 2005, said Dr Mike Storey, the Potato Council's head of research and development.
"It is a much more aggressive pathogen than the traditional blackleg bacteria. Its incidence is increasing," he said.
It was found in England and Wales in 2007 when seed samples were submitted for voluntary checks by growers. Another case was confirmed in 208, 16 in 2009 and 24 in 2010.
Dr Storey was presenting a summary on behalf of Ian Toth, of the James Hutton Institute, which was one of the leaders of research into dickeya. He had been unable to attend the conference because his flight from Edinburgh could not land at Norwich because of fog.
In his paper, he argued that growers could prevent further spread by sourcing home-grown quality seed potatoes and avoiding importing. Research in Sweden had identified seed potatoes from the Netherlands as a source of dickeya.
In Scotland, the developed administration had introduced legislation in 2010 setting "nil-tolerance" standards for dickeya. Dickeya had been detected in four ware potato crops in 2009 and nine more in 2010. However, although there had been no findings in Scottish seed, it was found in a survey in England and Wales.
In 2011, there were no findings of dickeya in ware or seed which was a reflection of the legislation and much more awareness by growers and consideration of the source of seed.
And the link with imported seed from Holland was obvious because all but two of the 22 samples of seed tested in the past two years were infected. In England and Wales, dickeya was found in 17 (6.7pc) of 243 certified seed samples in 2010. Last year, there were just five or 2.9pc of 173 seed stocks tested.
An investigation in Sweden had also identified dickeya as the source of infection, which had spread through Poland to become much more widespread by 2009. The import of seed potatoes from the Netherlands was responsible for most of the infection.
"This is emphasising the importance of seed as the source of origin of the disease and leading to its spread, said Dr Storey, who added: "It is a major threat to all production in Britain.
While dickeya was widely distributed around the world, it was this aggressive type, which was now of particular concern to the UK industry, he said.
Compared with the rest of Europe, Britain has made a stand to control the spread and incidence of dickeya, said Dr Storey.
SOURCE: Michael Pollitt, Agricultural editor, Edp24.co.uk