Detection and characterization of grapevine leafroll-associated viruses (GLRaVs) in Aegean vineyards

This study was carried out main viticulture production areas of Aegean Region from 2011 to 2015. The aim of this study, was to determine presence and prevalence of Grapevine leafroll-associated viruses (GLRaV-1, GLRaV-2, GLRaV-3, GLRaV-4, GLRaV-5, GLRaV-6, GLRaV-7, GLRaV-9, GLRaV-Pr and GLRaV-De) via serological (DAS-ELISA) and molecular (Real-time RT-PCR) methods; to indicate symptoms development for some isolates of selected samples on herbaceous and woody indicator plants with biological indexing and to examine the isolates of selected samples phylogenetic relationship with each other's and reported world isolates too. Between 2011-2012, samples which collected from Manisa, Denizli, İzmir, Aydın and Uşak provinces were performed DAS-ELISA and Real-time RT-PCR analyses for detection GLRaVs. At the end of DAS-ELISA and Real-time PCR assays 133 out of 424 samples were found infected at least one GLRaVs and the infection rates were 34,1%, 32,2%, 26,7%, 20% and 18,2% for Denizli, Manisa, İzmir, Uşak and Aydın provinces, respectively. Regardless the mixed infections, GLRaV-Pr was found to be the most widespread virus with 12% infection rate that followed by GLRaV-De (12%), GLRaV-3 (8,5%), GLRaV-2 (2,8%), GLRaV-4 (2,4%), GLRaV-9 (0,9%), GLRaV-1 (0,5%), GLRaV-5 (0,2%) and GLRaV-7 (0,2%) respectively. In addition GLRaV-6 was not detected within the collected samples. 133 out of 424 tested samples were found infected by one (22,2%) or more (9,2%) GLRaVs. In biological indexing assays on herbaceous indicators only the isolate of U-5 was indicated symptoms on Nicotiana benthamiana. On the contrary biological indexing on herbaceous indicators, the isolates were indicated various severity GLRaVs like symptoms on at least one woody indicators (Cabernet Franc, Cabernet Sauvignon and Pinot Noir). Phylogenetic analyses were indicated that obtained sequences belong to native virus isolates show high identity at nucleotide and amino acid levels with selected reference isolates. In addition 23 native virus partial genome sequences were recorded to NCBI genbank. GLRaV-9, GLRaV-Pr and GLRaV-De were firstly reported for viticulture areas in Turkey with this study.