7 August 1998

Rhizo affects all…

RHIZOCTONIA is responsible for more than just skin-finish losses, making seed treatment justified even for processing varieties when seed infection is identified, says Profarma.

It is not just about black scurf and skin finish, says agronomist Serena Eustice. Mis-shapes and giraffe necking are also symptoms of the fungus.

This damage makes the disease relevant to all growers, not just pre-packers. Whether treatment is worthwhile for processing growers comes down to the marketable yield loss, she says. At about £60/ha for full-rate liquid seed treatment, this could be less than 1t/ha (2.5t/acre).

However the disease can be soil-borne too, in which case growers should adopt additional controls of earlier lifting, with more resistant varieties, she adds.

This is what rhizoctonia does," says Profarmas Serena Eustice. The fungus that causes black scurf also leads to mis-shapen tubers. which can make seed treatment worthwile even in processing crops. Giraffe-necking (inset) is another symptom of the fungus.