The white grape variety (also known as Emerald) is a new cross between Emperor x Sultana Moscata. The crossing took place in 1939 and the selection in 1950 by Dr. Harold P. Olmo (1909-2006) at the California University of California. Incidentally, the same parents also produced the new variety Ruby Seedless. It was a crossing partner for the Marquis variety. The seedless variety is used as a winepress and table grape. No stocks were reported in 2016 (Kym Anderson statistics).
Pictures: Ursula Brühl, Doris Schneider, Julius Kühn-Institut (JKI)
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)