The white grape variety is a new breed between Schiava Grossa (Trollinger) x Riesling, which was confirmed by DNA analyses published in 2012. Synonyms are Geisenheim 3-48 and Wittberger. Incidentally, the same parents also gave rise to the two new varieties Kerner and Rotberger. The cross was made in 1928 by Heinrich Birk (1898-1973) at the Geisenheim Research Institute in the Rheingau. The vine is susceptible to botrytis. It produces white wines with high acidity, which are particularly suitable for the production of sparkling wines. However, the variety has not become established. No stocks were reported in 2018 (D-STATIS).
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)