USE OF IMMUNOASSAYS FOR THE STUDY OF NATURAL ASSEMBLAGES OF AQUATIC HYPHOMYCETES

Specific monoclonal antibodies raised in previous studies were used in a quantitative ELISA to determine the biomass of three species of aqu atic hyphomycetes: Tetracladium marchalianum de Wild, Anguillospora lo ngissima Ingold, and Alatospora acuminata Ingold. The use of these met hods for the study of mixed assemblages was assessed in the laboratory . The presence of nontarget fungi did not interfere with specific reco gnition by antibodies in the ELISA assay. The immunoassays indicated t hat lower biomass was attained by individual species colonizing field- incubated leaf material compared to laboratory-inoculated material. Al atospora acuminata attained the highest relative biomass on field-incu bated leaf material, and T. marchalianum the lowest. These results con trast sharply with those obtained using more conventional methods base d on conidial abundance. Conidia of T. marchaliamum were recorded more frequently than conidia of A. acuminata, and are, therefore, assumed to have had a higher relative abundance. The implications of these app arently conflicting results are discussed.