Problems encountered during immunofluorescent diagnosis of fireblight

Publisher Website
Google Scholar
Abstract
SUMMARY: An immunofiuorescent (fluorescent antibody or FA) staining technique was used to detect Erwinia amylovora (Burrill) Winslow et al. in plant tissue, but in preliminary trials it failed to do so in a majority of preparations from fireblight‐infected plants. Differential centrifugation greatly improved the rate of detection of E. amylovora in plant tissue. Ctiltures of E. herbicola subsp. ananas (Serrano) Dye, E. stewartii (Smith) Dye, E. rhapontici (Millard) Burkholder and two plant isolates (probably Pseudomonas fiuorescens (Trevisan) Migula and E. herbicola subsp. herbicola (Lohnis) Dye) cross‐reacted with E. amylovora in the FA stain. Of these only the Ps. fiuorescens isolate and a different plant isolate of E.h. subsp. herbicola cross‐reacted with E. amylovora anti‐serum in the slide agglutination test. Use of absorbed E. amylovora antiserum completely eliminated cross reactions in the slide agglutination test, but only partly removed cross reactions in the FA stain. Immunofluorescence appeared to be more sensitive but less reliable than conventional plating methods for fireblight diagnosis.