Green manures to control Verticillium wilt of strawberry

Abstract: The efficacy of different types of green manure plants to reduce the soil inoculum ofVerticillium dahliae, causal agent of Verticillium wilt, was tested in two different soils. A brownmustard (Brassica juncea) cultivar with a high content of glucosinolates (GSL) was used to test theeffect of biofumigation on the survival of V. dahliae microsclerotia in soil. The principle ofbiofumigation is based on the transformation of glucosinolates in isothio-and thiocianates (ITC),which are biocidal volatile molecules. A brown mustard cultivar with a low glucosinolate served toestimate the non-biofumigation effect of a Brassica green manure. Rye (Secale cereale) wasincluded to know the efficacy on V. dahliae of a non-cruciferous species. In a loamy soil, thestrongest reduction of V. dahliae microsclerotia was achieved with the high-GSL brown mustardand the lowest with rye. In contrast, in a sandy soil, rye was the most and high-GSL brown mustardthe least successful plant to reduce microsclerotia of V. dahliae.