DETECTION OF SPONGOSPORA-SUBTERRANEA USING MONOCLONAL-ANTIBODIES IN ELISA

Five hybridoma cell lines secreting antibodies (MAbs) recognizing zoos pores of S. subterranea were raised from splenocytes of mice. One MAb also weakly recognized plasmodia/zoosporangia and cystosori of S. subt erranea, and another recognized only plasmodia/zoosporangia in plate-t rapped antigen ELISA. Polymyxa graminis was recognized most strongly o ut of 26 micro-organisms other than S. subterranea against which the M Abs were tested. Most were recognized only weakly or not at all. The M Ab that recognized zoospores of S. subterranea most strongly detected as few as three zoospores per microtitre plate well when 12 replicate wells per treatment were arranged randomly on plates and absorbance va lues subjected to analysis of variance. The sensitivity of detection w as not improved by mixing antibodies, using a biotin-streptavidin ampl ification system, or by using a double antibody sandwich system. Zoosp ores of S. subterranea flushed from soil were detected only after unre alistically large numbers of cystosori had been added. They were not d etected in samples of naturally infested soil removed from a field sho rtly after a severely scabbed potato crop had been harvested.