Abstract
Content of this study was the evaluation of 12 different rootstocks with 'Welschriesling', which is a very important grape variety for the wine-growing region Styria. The test site is located in region of high precipitation in the southernmost part of Styria on a medium-shallow deep ripped soil on limestone marl. Data collection over 16 years revealed significant differences in many parameters. The lowest stability was observed in the test variants C3309 and 161-49C with 55 % and 40 % failure rates, respectively. The rootstock varieties 5C, 5BB, 8B and Binova proved their high stability. Pruning weights and trunk diameters showed the strongest growth for the rootstocks 1103P, 5BB and 420A. The weakest growth was shown by grafting combinations on 161-49C and C3309. Suckers could only be seen on 1103P and Ganzin 9 (on 20 % and 5 % of the vines, respectively). Significant differences in the nutrient content of the leaf blades were found for nitrogen, phosphorus, potassium, calcium, magnesium, iron and copper. The highest nitrogen contents were measured in the test-variants with 5C and Binova and the lowest values with Ganzin 9. The leaf blades of the test-variants 1103P, 5C and 5BB contained the most phosphorus, and 161-49C, C3309 and Börner contained the least. For the element potassium, the contents were highest at 161-49C, SO4, C3309 and 8B, and lowest at 1103P and Ganzin 9. The highest calcium contents were found at 1103P, 5C and 5BB and the lowest at Ganzin 9 and C3309. 1103P and C3309 absorbed magnesium very efficiently, while Ganzin 9 and SO4 were the least efficient in this regard. Magnesium deficiency symptoms on the leaves were least pronounced in varieties 1103P, C3309 and Fercal. More copper in the leaf blades was found in 1103P and Ganzin 9, but little in 161-49C, C3309, Börner and 420A. The highest iron concentration was detected in 5BB and 1103P and the lowest in Börner and Ganzin 9. The time of berry ripening occurred the latest for Ganzin 9 and 1103P and the earliest for Börner, 161-49C and C3309. 161-49C produced the least compact bunches and was therefore significantly different from 420A, Binova, Fercal, C3309, 8B and 5BB. No significant differences were found in susceptibility to grape rot. The rootstock varieties 1103P and 420A produced the best yield performance. When dealing with drought, the 1103P and Fercal vine rootstocks tended to be more tolerant.