First report of Grapevine pinot gris virus in German vineyards.
During a field survey conducted in 2015 in the state of Baden-Württemberg (Germany), symptoms resembling those caused by a viral infection (short internodes, zigzag growth of shoots, disturbed berry development) were observed in Vitis vinifera cv. Riesling vines in a commercial vineyard. Thirty vines were analysed and were positive by RT-PCR using the Grapevine Pinot gris virus (GPGV)-specific primer pair DetF/DetR. The RT-PCR amplicons from 3 vines were cloned and sequenced. The 3 amplicons shared a high identity (99%). Sequence analysis results revealed a 99% nucleotide sequence identity with the Slovak isolate SK30 of GPGV. To check the presence of other viral pathogens or undetected divergent viral variants, small interfering RNAs isolated from one symptomatic Riesling plant were analysed using next generation sequencing (NGS) performed by the Illumina platform. Besides GPGV, this analysis identified 3 other infecting agents (Grapevine rupestris stem pitting-associated virus, Hop stunt viroid and Grapevine yellow speckle viroid 1). The full-length genome sequence of GPGV was obtained by combining the results of mapping of the Illumina reads on a reference GPGV genome, Sanger sequencing, and RACE PCR. This is thought to be the first official report of GPGV in Germany.