Detection of Spiropiasma citri in plants and insect hosts by ELISA.

Enzyme-linked immunosorbent assay (ELISA) was shown to be a sensitive method for the detection of Spiroplasma citri in plants and insect hosts. S. citri was detected in Vinca rosea less than 1 week after infection by grafting, and reached a peak titre of up to 109 spiroplasmas per gram of tissue in infected shoots and root tips. Multiplication of S. citri in the leafhopper Euscelidius variegatus was also monitored by ELISA. S. citri could be detected in a single insect, showing that this technique is suitable for screening insect populations to the field for potential vectors of spiroplasma diseases. A method is described for raising a pathogen-specific antiserum from r. rosea infected with S. citri which reacted with cultured S. citri and also with S. citri in plant tissue. [ABSTRACT FROM AUTHOR]