Based on a field trial, the impact of three different viticultural management practices on photosynthetic activity of Vitis vinifera cv. Riesling were compared. The vines were planted in 1991 at Geisenheim (Rheingau, Germany) and the different management practices i.e. integrated (good agricultural practice), organic (EU VO 834/07 and ECOVIN standard) und biodynamic (EU VO 834/07 and DEMETER standard) were established in 2005.
Even though all treatments received the same level of nutrients and water the initial measurements of photosynthetic activity differed tendentially. The integrated and biodynamic treatment showed a slightly higher degree of light saturation, as well as photosynthetic activity, compared to the organic treatment
