There seems little hope that sclerotinia, a soil borne fungus disease which costs carrot, lettuce and potato growers an estimated £6 million a year will be eradicated, according to Dr Mark McQuilken of the Scottish Agricultural College.
However, despite this, he believes the disease can be controlled and kept to “an economic threshold”.
A four-year research programme is underway at Warwick University, funded by Defra, and there is interest in a Norwegian approach, which uses DNA readings in the soil which can identify the possible presence of sclerotinia prior to planting.
While onions may not share the same problems, growers are also losing money through the presence of downy mildew, leaf blotch and leaf spot. Stefan Williams, technical manager of P.G. Rix (Farms), believes the loss to be approaching £2.8m.
Particularly susceptible were red onions, where production was expanding, and some southern hemisphere Grano types.
A research product part funded by the Horticultural Development Council has shown that some older, cheaper products were still outperforming newer treatments, but breeders were making progress with resistant varieties
