Investigations on the preservation of the South Tyrolean grape variety Vernatsch
Recently, a project which can be traced back to the late-1980s, was successfully concluded. In the context of extensive selection work in old South Tyrolean Vernatsch vineyards, more than 300 individual planting stocks were reproduced. After thorough testing, in the summer of 2020, four new Edelvernatsch clones were homologized and entered into the National Registry of Grape Varieties.
For years, the amount of acreage in South Tyrol under cultivation with the Vernatsch variety has been declining. Laimburg Research Centre thus wished to preserve the biodiversity of this typical South Tyrolean grape variety. The goal was to filter out suitable biotypes from the gene pool which had been selected back then – biotypes which meet the modern quality requirements. Besides its ability to adapt to different terroirs and its affinity for various different grape rootstocks, special attention was paid also to the suitability of its vine clones for wire frame training. Traditionally, Vernatsch is trained on pergolas. Extensive investigations at Laimburg Research Centre have shown that Vernatsch is also suitable for wire frame training. Besides clones and rootstocks, the investigations focused also on vine pruning and different spacing.
Analysis of wine quality
Another important aspect in clone selection is grapevine health. Only healthy vines – i.e., vines which are free of infection with the most important vine viruses and phytoplasmas – come under consideration.
Nevertheless, the decision for or against cloning a particular biotype is ultimately dependent upon the corresponding wine quality. For this reason, the grapes of the clones under investigation are vinified according to a standard procedure, subjected to analytical and sensory testing, and compared with already approved clones in a years-long process.
