First report of Grapevine yellow speckle Viroid-2 infecting grapevine (Vitis vinifera) in Thailand.
From February to March 2014, 22 leaves from the grape (Vitis vinifera) cultivars Black Opal seedless, Black Queen and Pok Dum were sampled from 8 vineyards in Saraburi (4 samples) and Nakhon Ratchasima (18 samples) provinces, which are the major grapevine plantation regions in Thailand. Various symptoms were found, including leaf roll with red colour, leaf malformation, vein banding and yellowing, yellow spots and yellow flecks (speckle). The causal pathogen was isolated and identified as Grapevine yellow speckle viroid-2 (GYSVd-2) based on various molecular analyses. This is thought to be the first report of natural GYSVd-2 infection in grapevine in Thailand.