Development of a Multiplex TaqMan Real-Time PCR Assay for Sensitive and Rapid Detection of Phytoplasmas Infecting Rubus Species

Rubus stunt, a disease associated with phytoplasma infections in wild and cultivated Rubus species, is a major challenge in the production of raspberries, blackberries, and loganberries. Phytoplasmas are cell wall-less bacteria inhabiting the phloem and are transferred by phloem feeding insects. As the time between infection of a plant and the development of disease symptoms can take up to 1 year, an early detection of phytoplasmas using highly sensitive and rapid molecular methods is of great importance to minimize their spread. Therefore, in this study, a multiplex real-time PCR assay using TaqMan probes in combination with four different kinds of fluorogenic dyes in the same reaction was developed, allowing a rapid and simultaneous detection of different groups of phytoplasmas infecting Rubus species. This assay is a solid tool for the screening of mother plants in nurseries and for further research in phytoplasmas infecting Rubus