Universal primers for plasmid detection and method for their relative quantification in phytoplasma-infected plants

Abstract

Abstract Rep gene occurring in the majority of plasmids associated with phytoplasmas was selected as a target for real-time PCR together with single-copy Tuf gene from the phytoplasma genome. Rep-specific primers amplified products from host plants infected with phytoplasmas of groups 16SrI, -II, -III, -V, -X, and -XII. Relative concentrations of plasmids ranged depending on strain from 1-2 copies to several hundred copies per each phytoplasma studied. Primers targeting the rep gene are proposed for direct PCR detection of phytoplasma plasmids from experimental periwinkle host as well as from natural plant hosts