Synonym or breeding number (also FR 392-83) for the grape variety Souvignier Gris; see there.
The white grape variety is a new breed between Seyval Blanc x Zähringer. The true parentage was only determined by DNA analyses carried out in 2016; until then Cabernet Sauvignon x Bronner was accepted. It contains genes from Vitis lincecumii, Vitis rupestrisVitis...
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Sigi Hiss
freier Autor und Weinberater (Fine, Vinum u.a.), Bad Krozingen