“…In the absence of suitable host plants, these sclerotia may survive for many years (ColeySmith and Sansford, 1986). Although germination of sclerotia has been reported to occur at a low level in the absence of host plants (Merriman at al., 1981;Crowe and Hall, 1980), it is generally a very specific response to compounds released by Allium species (Coley-Smith and Holt, 1966;Coly-Smith and King, 1969). This germination response can be induced by treatment of sclerotia with Allium extracts (Crowe and Hall, 1980), artificial onion oil (Merriman et al, 1981) or diallyl disulphide (DADS) (ColeySmith and Parfitt, 1986).…”