“…nasturtii has been developed. Claxton et al (1995) described a system for releasing zoospores from crooked roots placed in a solution of nutrients, which provides a crude method of quantification, but this approach is laborious and takes at least 3 days to perform. Approaches based on monoclonal or polyclonal antibodies have not been attempted on this pathogen, but they have been tried with other plasmodiophorids: such attempts to use antibody-based assays for plasmodiophorid detection have frequently encountered difficulties with sensitivity in soil (Harrison et al, 1993;Wallace et al, 1995;Wakeham & White, 1996;Walsh et al, 1996) and an inability to distinguish between live and dead resting spores (Harrison et al, 1993;Walsh et al, 1996), although this latter limitation may also apply to DNA.…”