What are fungus resistant grape varieties (PIWIs)?

Cabernet blanc

„PIWI“ is a German abbreviation and stands for fungus resistant grape varieties. These were created by crossing European grape varieties and American fungus resistant varietals.  Most of them still are known as hybrids or interspecific varietals and were first used in France from 1880 to 1935. The aim was to combine the good resistance to diseases and phylloxera of the American grape varieties with the high quality of European varietals. Unfortunately these new varietals were not able to survive on their own root.

New cultures, which have been grown after 1950, are very complex, may have been created with Asian varietals and are the result of decades of crossings. They belong to the type Vitis vinifera because they are not to be distinguished taxonomically. An official examination in comparing different grape varieties has proven the high quality in wine production of Piwi varietals. This is why, winemaking with Piwi varietals is allowed by European law.

Since which moment in time do European grape varieties suffer diseases?

The two diseases, which require the most treatments in viticulture, are the downy and powdery mildew. Originally these fungus illnesses were not a problem in European viticulture, since they were not native. Only in the 19th century these diseases were imported with new varietals from Northern America. Within a short period of time the diseases spread significantly all over Europe. Viticulture in Europe was to be ruined completely, also because of the phylloxera, which devastated vines at the same time. This is the reason why every year traditional grape varieties have to be treated chemically 6 – 16 times, depending on weather conditions. Every time a wine grower treats his vines, he sprays chemicals on them and this is how theses substances end up in nature. According to analysis by the European Institute of Statistics (EuroStat), the use of chemicals in viticulture is much higher than the same use in any other agricultural sector within Europe.

Do act and not only react!

Your first choice should be a fungus resistant grape variety, because any type of pest management will not solve the problem of pollution. Of course this still doesn’t mean that there might not arise any other challenges. This is due to the fact that vines, if they are planted in monocultures may attract also other vermins, such as insects or virus, which ones again require treatments of some kind. Maybe one day there will be even a mutation of the above stated illnesses, which might once again lead to the damage of PIWI grape varietals.

As far as the present and nearer future are concerned though, PIWI varietals represent for sure the best choice to do something against pollution. Sustainable viticulture is possible! PIWI is reality and the only way to use no chemicals and to decrease soil pollution by also running less your tractor.