The effect of the rootstock SO4 on the wine quality in comparison to the rootstocks 1103 Paulsen, 140 Ru, 420 A and Börner

In a steep slope with limited soil thickness, a rootstock comparison was established in 1999 with the Pinot Blanc variety and the rootstocks SO4, 1103 Paulsen 140 Ruggeri, Börner and two clones of 420 A in 5 randomised repetitions. From 2018, in the 20th year of the vineyard's existence, small-scale vinifications were carried out in three consecutive years and the wines were evaluated sensorially. In addition, ascertainments were carried out in the experimental vineyard to determine the growth strength of the rootstocks and their drought tolerance. Hardly any statistically significant differences could be found in the evaluations. At the tastings of the wines, a tendency towards atypical aging of the wines from Paulsen 1103 and 420 A clone SMA was noticeable. Furthermore, rootstocks 1103 Paulsen and 140 Ruggeri showed a tendency towards more growth and better drought stress tolerance compared to the other rootstocks. Both clones of rootstock 420 A fell sharply in their vegetation development in the field replicates with somewhat less favourable soil conditions, which was not observed to a comparable extent by the other rootstocks.