New detection method for phytoplasmas
A new universal PCR detection method has been developed in Maryland (US) to detect phytoplasmas. Two pairs of universal primers can specifically initiate amplification of 16S rRNA sequences of 19 phytoplasma (representing all known 16S rRNA groups). No amplification was obtained with 48 related mollicutes (except an Acholeplasma sp. but this type of organism has never been found in living plant tissues) and some plant pathogenic bacteria and other prokaryotes. Compared to direct PCR assay, the nested-PCR was more sensitive and phytoplasmas could be detected from all woody hosts and insects tested. In addition, the RFLP analysis of the PCR products obtained can allow the specific identification of the phytoplasmas present in plant tissues. The authors felt that this method is particularly useful for etiological studies of unknown diseases which are suspected to be associated with phytoplasmas and also for testing plant material in certification programmes.
Sources
Gundersen, D.E.; Lee, I.M. (1996) Ultrasensitive detection of phytoplasmas by nested-PCR assays using two universal primer pairs.
Phytopathologia Mediterranea, 35(3), 144-151.