SLU news

Biological control of fungal disease in carrots

Published: 24 April 2012

Treatment of carrot seeds with a certain soil bacteria can reduce storage losses caused by an increasingly common fungal disease. The treatment was developed by researchers at SLU.

In recent years, the problems have increased with the storage disease Acrothecium carotae in carrots. The roots are attacked in the field, but symptoms appear as black dimples on the long-stored carrots. Infected carrots must be discarded. As with any storage diseases Acrothecium major causes major financial losses for growers who already have had expenses for harvesting and storage of the product.

There will be opportunities already this year for organic farmers to use carrot seeds that are treated with the soil bacterium Pseudomonas chlororaphis (under the product name “Cedress”) in order to reduce the problems with this costly and serious disease.

Soil bacteria have a number of different effects that can affect the fungus negatively, for example through direct competition for nutrients and space, but also by stimulating the plant's own defence, known as induced resistance. The results have been very promising in field trials conducted in carrots.

Cedress was developed within the research program MASE at SLU and is produced by Lantmännen BioAgri.