Sub-varieties and Crossings
In the Trentino-Alto Adige region, several sub-varieties or clones of Trollinger have been identify. These include the large berry Schiava Grossa (also known as Grossvernatsch and Schiava Grigia) which is probably the highest yielding clone but tends to produce light bodied and neutral tasting wine, the smaller berry Schiava Gentile (also known as Kleinvernatsch) which tends to produce more aromatic wines and Tschaggle which is the lowest yielding clone but often produces the most critically acclaimed wines. Other known clones include Schiava Media and Schiava Piccola.
In Württemberg, Trollinger was crossed with the white grape Riesling to produce the cross Kerner in 1929 (received varietal protection and was released for general cultivation in 1969). The new crossing was named after the local poet and medical writer, Justinus Kerner. The variety was also crossed with Muscat of Alexandria to produce Black Muscat.
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