Five viroids are reported to infect grapevines (Flores et al., 2005) Which include Hop stunt viroid (HSVd), Citrus exocortis viroid (CEVd) two Grapevine yellow speckle viroids 1 and 2 (GYSVd-I and GYSVd-2) and the Australian grapevine viroid (AGVd).We already reported that vineyards in Northwest Iran are infected by multiple viroids . But, there is no study on molecular characterization of grapevine viroids in this part of Iran. This paper reports a new proposed type of GYSVd-1-type 4 in Iran based on sequence variations.
