Study of Grapevine fanleaf virus Distribution in Iran Using Test Plants, DAS-ELISA and IC-RT-PCR

Fanleaf degeneration, a disease caused by Grapevine fanleaf virus (GFLV), is considered as the most destructive grapevine viral disease worldwide causing severe losses in vineyards, annually. GFLV is apparently believed to have originated from ancient Persia and therefore, to restrict it in its further infections, a precise identification along with a monitoring of its distribution pattern is crucial. Distribution and relative rate of infection to GFLV in vineyards and nurseries from some different parts of Iran was studied. A total of 882 cuttings were collected from Karaj, Bavanat, Shiraz, Jahrom, Maymand, Ourmia, Naghadeh and Abhar. Infection was confirmed in 204 samples using such different diagnostic methods as mechanical transmission to test plants, as well as serological and molecular techniques. Results confirmed GFLV infection in some new regions of Iran for the first time, including some nurseries in Karaj and some in Naghadeh city. The most severely infected samples were observed in Bavanat, while 63.7 percent of the samples being infected. No infection was detected in Abhar city. Infection varied from 1.8 to 43.1 percent in the other regions. Results proved widespread distribution of GFLV races to different regions of Iran, confirming the fact that it had been spread from its believed origin through infected cuttings and scions.