In a field survey, conducted during 2012-2014 in Bulgaria, symptoms of foliar reddening were observed on celery in the locality of the village of Stryama, near Plovdiv. Leaf samples from 9 symptomatic and 5 asymptomatic plants were collected and tested for phytoplasma presence detection. Nested polymerase chain reaction (PCR) analyses using universal primer pairs P1/P7 followed by R16F2n/R2 identified the presence of phytoplasmas in all symptomatic plants, while asymptomatic plants were tested negative. Restriction analysis of amplified 16S rRNA fragments with MseI enzyme identified in all positive samples the same pattern as a reference strain of stolbur phytoplasma belonging to the 16SrXII-A ribosomal subgroup.
Molecular diagnostics of stolbur Phytoplasma disease in celery Apium Graveolens L.