Use of optimised PCR methods for the detection of GLRaV3: A closterovirus associated with grapevine leafroll in Tunisian grapevine plants

We report a modification and optimisation of a previously published procedure (Minafra and Hadidi, 1994) for the detection of GLRaV3 in infected grapevine plants. GLRaV3 RNA was successfully detected not only in total crude nucleic acid extracts of infected grapevine tissues but also in viruliferous mealybug extracts by IC-RT-PCR. This detection was rapid, sensitive and specific without occurrence of any background. A comparative ELISA, RT-PCR and IC-RT-PCR assays were carried out and revealed the greater sensitivity and specificity of PCR techniques.