Multiplex rt-pcr method for the simultaneous detection of nine grapevine viruses

Viral diseases are a serious pathological problem for grapevines, and in recent years the need for increasingly specifi c and rapid diagnostic methods for the selection of propagation materials has grown. Arabis mosaic virus, Grapevine fanleaf virus, Grapevine virus A, Grapevine virus B, Grapevine rupestris stem pittingassociated virus, Grapevine fl eck virus, and Grapevine leafroll-associated viruses 1, 2, and 3 are nine of the most widespread viruses that naturally infect grapevines. A multiplex RT-PCR was developed for simultaneous detection of these nine grapevine viruses, in combination with a plant RNA internal control used as an indicator of the effectiveness of the reaction. One to ten fragments specifi c for the viruses and an internal control were simultaneously amplifi ed from infected samples and identifi ed by their specifi c molecular sizes in agarose gel. The protocol reported is an update of previously published protocols for RNA extraction and multiplex diagnosis of viruses. After several years of use and hundreds of samples tested, and following validation in several laboratories, this multiplex RT-PCR provides a reliable and rapid method for detecting grapevine viruses from a large number of samples.