Short name for "fungus-resistant vines", the intersections between Europeans Vines and fungus resistant species of American vines have emerged. Occasionally, they are also referred to as fungus-resistant, fungus-tolerant or simply robust varieties. Newer breeds are very complex and they can too Asians Vines especially because of the also desired resistance against frost be involved. It follows that all these grape varieties are not with the help of Genetic Engineering, that is, without gene transfer, were bred. Most varieties today as hybrids. interspecific Varieties or falsely verallgemeindernd direct carrier (Hybrids are not necessarily direct carriers), which were created between 1880 and 1935 in France. One wanted the resistance of the American vines against mushrooms (especially mildew ) and the phylloxera to combine with the quality of the European species Vitis vinifera. The hope, these vines could be grown despite phylloxera directly (standing on its own root), but unfortunately not fulfilled.
Fungal resistance means more or less resistant to the various fungal diseases (especially true and false mildew as well as gray horse = Botrytis ), which are all worldwide. These infest all traditional grape varieties; such a fungus attack can totally destroy the grape harvest. The traditional grape varieties have to be six to ten times each year fungicides be treated, which means a corresponding environmental impact. This can be significantly reduced to less than half with PIWI varieties. Many of the varieties are as well frost resistant, Accordingly, especially in biological, as well as other forms of production like biodynamic and Bioenergetic viticulture increasingly used such varieties.
Known PIWI new varieties are among others Blütenmuskateller. bolero. Breidecker. Bronner. Cabernet Cantor. Cabernet Cortis. Calardis blanc. Divico. Divona. Danube Riesling. Danube Veltliner. Evita. Johanniter. Jutrzenka. Malverina. Merzling. monarch. Muscaris. Pinot Nova. regent. Rathay. Roesler. rondo. Solaris and Souvignier Gris, However, the list does not claim to be exhaustive, as there are also a number of older new breeds that have lived up to the name PIWI, which has become popular in recent years. All varieties include European, American and some of their parents Vitis amurensis also Asian genes, therefore there is a problem within the EU regarding the use for quality wines, Although this is nowhere near as strict as it was a few years ago, many varieties of American genes are still not (yet) approved for quality wines (see below) hybrids and Quality wine-grape varieties ).
An international consortium for promotion of fungus-resistant grape varieties (PIWI International) was founded in 1999 in Einsiedeln (Switzerland) and has more than 250 members, mainly from the German-speaking countries Germany, Austria, Switzerland, Lichtenstein and Italy (South Tyrol) but also from Hungary. Czech Republic, France, Ireland, Holland and the USA. Many members come from the field and grow their own PIWI vines. In addition, too nurseries as well as various grape breeders and state research institutes of the consortium. Especially the wine institute in Freiburg (Bathing), but also others like Changins (Vaud, Switzerland), Geilweilerhof (Palatinate) and Geisenheim (Rheingau) deal with the new breed of PIWI varieties. The aim and purpose of the PIWI working group is to exchange scientific and practical knowledge in the field of PIWI grape varieties at national and international level and to give suggestions. Among other things, meetings or regional working groups are therefore periodically held. See also a list of relevant keywords below grapevine,
Pictures: Ursula Bruehl, Doris Schneider, Julius Kühn Institute (JKI)