USE OF THE REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION FOR THE DETECTION OF PELARGONIUM FLOWER BREAK CARMOVIRUS

A polymerase chain reaction (PCR)-based assay was used to detect pelar gonium flower break carmovirus (PFBV) in total RNA extractions made fr om infected Pelargonium plants. Extracts were reverse transcribed (RT) and the resultant cDNA was amplified by PCR, using oligonucleotide pr imers specific for 343, 510 and 832 base pair fragments of the RNA-dep endent RNA polymerase gene of PFBV. The specificity and sensitivity of RT-PCR were compared with the enzyme-linked immunosorbent assay (ELIS A) for the detection of PFBV in Pelargonium tissues. The virus could b e detected efficiently in high dilutions of sap from infected plants a nd at low concentrations of purified virus. Although ELISA is a powerf ul tool for virus detection, RT-PCR was over 1000 times more sensitive in detecting PFBV in leaf extracts of infected Pelargonium than was E LISA. The limit of detecting PFBV RNA by RT-PCR was 200 fg, compared w ith 200 pg of virus by ELISA.