Since 2010, sunflower in France has been severely affected by a vascular wilt disease caused by Verticillium dahliae. Disease is widespread and causes significant damage up to 30% yield loss. V. dahliaeis a soil-borne fungus living in roots able to survive in the absence of a host in the form of microsclerotia (MS). Brassica crops used as cover crops can naturally suppress soilborne pathogen viability. This fumigation activity has been linked to volatile isothiocyanates (ITCs) released from glucosinolates (GSLs). In this study, Brassicacover crops of white and brow mustard, radish, rape and rapeseed were evaluated for their ability to reduce the viability and development of V. dahliae. Cultivars were selected by GSL side-chain and concentration, and V. dahliaestrain for its aggressiveness on sunflower. Biofumigation was assessed in a laboratory assay. MS and developed V. dahliaeon growing media were exposed for 20 days to volatile compounds released by fresh or freeze ground plant tissues. The toxicity of ITCs-GSLs on V. dahliaewas assessed by the area under fungus progress curve relating its development on the media. The five Brassicareduced the development and germination of V. dahliaeby 90% (brown-mustard) to 63% (radish), and the development by 90% (rape) to 69% (white-mustard) compared to the control in absence of tissues. Aliphatic GSLs in brown mustard and rape, and indole GSLs in rape and radish may explain the strong reduction of V. dahliaedevelopment and viability respectively. These results indicate that Brassica have potential for use as cover crops for the control of soilborne disease problems and sunflower wilt.