Verticillium Stem Stripe in Oilseed Rape

Verticillium longisporum is a soil-borne pathogen of brassicaceous crops, including the economically important oilseed rape. Its life cycle begins with dormant microsclerotia that can persist in soil for many years due to suppression of germination by soil bacteria. In the rhizosphere, plant root exudates can offset this suppression, triggering germination of adjacent microsclerotia, which enables root infection and subsequent colonization of the host xylem. Unlike other Verticillium species, V. longisporum only partially colonizes the vascular system, resulting in yield reduction without wilting but causing characteristic lateral stem striping symptoms. Verticillium stem stripe is among the major biotic stresses of oilseed rape in Europe and has recently gained increasing attention in Canada. Yield losses are difficult to quantify, as they vary considerably between years and locations. This variability is likely driven by environmental factors influencing microsclerotia germination and the extent of vascular colonization, including soil temperature, moisture, root exudates, and the soil microbiome. Currently, no effective chemical control measures or genetically resistant cultivars are available. However, promising sources of quantitative resistance have been identified and hold potential as an effective and sustainable management strategy. This case study provides an overview on the pathogen’s disease cycle, its pathogenicity and interaction with oilseed rape, and offers perspectives on future research and management directions.