The two varieties are interspecific new varieties created in 1964 by the breeder Vilém Kraus (1924-2013) in what was then Czechoslovakia. The white grape variety GM 6493 is a cross between Zarya Severa x Muskat Ottonel, the red grape variety GM 6494 is a cross between Zarya Severa x St. Laurent. Both hybrids contain genes from Vitis amurensis and Vitis vinifera. Both varieties are characterised by high resistance to both mildews and frost hardiness. Kraus offered some grapevine cores to Dr. Helmut Becker (1927-1990), then head of the Rebeninstitut Geisenheim (Rheingau), who recognised the importance of the breeding material and made selections. It was only here that they received their present names and also reached other institutes.
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