Leptosphaeria maculans

Is a fungal disease agent of stem canker on oilseed rape (OSR), which causes losses throughout Europe, amounting to greater than 20% seed yield if uncontrolled. Use of fungicides is usually only partially effective due to difficulties with timing, and resistance genes are used in breeding programmes to prevent systemic movement of the organism to the stem base. Major gene resistances are very effective, but changes in the organism have led to erosion of their effectiveness. This provides an example of an indigenous and established disease where emergent pathotypes have the potential to cause significant and rapid loss of a major control element.

Oilseed rape and wheat are two crops of major importance for domestic and industrial uses in Northern Europe. They are often used in rotations in agronomical practices. Both M. graminicola and L. maculans are characterized by the importance of crop debris in their fungal life cycle. They are two very interesting targets for conventional control methods based on sustainable use of pesticides (efficient for a whole rotation at the agrosystem scale) or more innovative methods based on discovery and exploitation of other micro-organisms competing with L. maculans and M. graminicola for nutrient sources, inhibiting its sexual reproduction or directly toxic for the fungi during the saprophytic stages. EMPHASIS will target L. maculans for early action on detection within WP2 (sentinel crops). In WP3 both fungal diseases L. maculans and M. graminicola will be targeted for the wheat – OSR rotation: biological control agents (microbes) will be screened concomitantly on both wheat and OSR debris to develop methods for fungal disease management (including optimized use of chemicals and debris management) for a whole rotation at the agrosystem scale.

Management approach

For Biological monitoring: Early detection of wind-borne pathogens through extensive sentinel plots.

For biological control agents: Metagenomic microbiological & epidemiological approaches for identifying microbes as potential bio-controls

Cultural controls: Rotation and crop management

Solution proposed by EMPHASIS

For Biological monitoring: An early detector network of sentinel plot locations appropriate for monitoring infection potential of target pathogens (PU) for increased understanding of disease cycle; and Potential identification of BCA’s

For biological control agents: Screening of microbial BCAs candidate for L. maculans and M. graminicola control on debris (PU)

Cultural controls: Guidelines for crop debris management and enhancing the action of some microbes as direct or indirect biological control in a wheat/oilseed rape rotation (PU) and Protocol for debris management

Contact person/organisation

Frederic Suffert (INRA)