Development of immunochemical and PCR methods for qualitative detection of Tilletia species in organic seeds

A rapid and sensitive detection of Tilletia species in contaminated cereal grains could enhance the quality of organic seed production and would also improve quarantine regulations. The final aim is to develop methods based both on molecular and immunological techniques for determination and differentiation of fungal species causing smut diseases mainly on seeds produced under conditions of organic farming. First results demonstrate that it is possible to verify an infection with Tilletia caries in freshly harvested grains in less than 5 h by Western blotting and in less than 3 h by PCR. The specific primer-pair developed for T. caries does not show any signifi- cant reactions with T. controversa or other seed-borne fungus pathogens like fusarium. In Western Blots using a polyclonal antiserum against T. caries spores, a specific reaction in form of a single band was observed when total spore-protein extracts were analyzed in the gel. In addition, there was no cross reaction to the protein extract prepared from T. controversa spores. Further methods for the specific detection of T. controversa and T. indica by PCR, ELISA or Western blotting are in development.