DASELISAs were conducted according to Clark and Bar-Joseph (and McLaughlin and Chen with the trapping and conjugated antibodies at a dilution of 1:400. Results of the ELISAs were determined by measuring absorbance of each well at 405 nm with a plate reader(Dynatec, Chantilly, VA) when the E. tracheiphila(ATCC 33245) bacterial culture(diluted to approximately 106 CFU) control absorbance reached 1.0 A405. The two antisera were compared by testing with DASELISA the original E. tracheiphila isolates and similar bacteria (E. amylovora, E.carotovora pv. carotovora, E. herbicola [=Pantoea agglomerans], and E. stewartii [=Pantoea stewartii subsp. stewartii]) maintained at Pennsylvania State University.All bacteria were diluted to approximately 106 CFU. Antisera produced for this study were also compared with antisera produced against an Arkansas strain