OPTIMIZATION OF SEROLOGICAL DETECTION (ELISA) OF THE QUARANTINE BACTERIUM PSEUDOMONAS-SYRINGAE PV PISI, USING IGY-TYPE ANTIBODIES FROM CHICKEN EGG-YOLK AND SELECTION OF A PEA CULTIVAR FOR BIOTEST

Serological detection of the quarantine bacterium Pseudomonas syringae pv. pisi, causing blight in Pisum sativum was affected in direct DAS-ELISA with a detection limit of 5 x 10(4) cells/ml 1:5 diluted sprout sap and 9 x 10(5) cells/ml 1:5 diluted seed sap. This ELISA variant had proved more sensitive than three others. Comparison of the suitability of IgY-type antibodies directed against the pathogen and raised in chicken egg yolk with that of IgG-type antibodies from rabbit serum showed similar detection limit. The reliability of positive ELISA signals was ensured by proving no cross-reaction of Igy with 12 heterologous bacterial pathogens and by testing IgY arid IgG for antigen-unspecific adsorption. The yield (mg) of IgY was 20 times superior to that of IgG in the same period of time. Of several cultivars, Pisum sativum cv. 'Konservenkonigin' showed typical symptoms already 9 d after inoculation under controlled growth conditions. For sanitation temperature treatment (microwave; 50-100-degrees-C) and several chemical disinfectants effected 100% inactivation of the pathogen.