Integrated control of Leptosphaeria pathogens on UK winter oilseed rape

Phoma stem canker is a damaging disease of oilseed rape in the UK, leading to yield losses > £100M p.a.

despite the use of fungicides. This disease is caused by two related pathogens: Leptosphaeria maculans

and L. biglobosa. However, current control of the disease focuses only on L. maculans. Recent work

showed that L. biglobosa can cause substantial yield losses and that it is less sensitive to triazole

fungicides than L. maculans. L. biglobosa is a threat to oilseed rape production in the UK since no

methods have been developed to control it. This project will investigate stem canker epidemics caused

by L. biglobosa, determine the proportions of L. biglobosa and L. maculans in pathogen populations,

screen cultivar resistance against L. biglobosa, determine efficacy of different fungicides for control of L.

biglobosa as well as L. maculans. The new knowledge about the pathogens, host resistance and efficacy

of fungicides will be used to develop new control strategies that ensure both pathogens are targeted.