Roots and rhizosphere microbiota diversity is influenced by rootstock and scion genotypes: can this be linked to the development of the grafted plant?  

Nitrogen fertilisation of grapevines is known to influence not only plant development and production yield, but also yeast assimilable nitrogen (YAN). This parameter is related to the growth of yeast

The trial was conducted in variety/rootstock Riesling/Kober 5 BB in the vineyard district of Vrsac. The vineyard was planted in 1996 on a south-facing slope, with rectangular type pruning of 3×1 m. The training system is of symmetric cordon type and mixed type pruning is practiced.

To characterize a wine, the most frequently used criteria describe its color, its origin, the grape varieties from which they come, or even for white wines its residual sugar content (dry, semi-dry, sweet). In france, the system of appellations of origin set up in 1919 was initially based solely on the notoriety and origin of the wines. But given the unfavorable consequences that this lack of details generated, the public authorities quickly integrated in 1927 into the “capus” law criteria for access to designations of origin, relating to the specific characteristics of the soils of the vineyards and the grape varieties used, in particular exclusion of interspecific hybrid varieties. In 1935 the creation of the aoc system confirmed the interest in precisely defining all the production conditions that must be implemented to be able to claim the benefit of an aoc, and grape varieties were an essential condition for acquisition.

The grapes producing and wine making regions are différent in their use of agricultural, industrial or agroindustrial means. These means are quite often very original and/or specialised; and lately are also quite competitive. Such means are being defined with increased accuracy in the delimitation and definition of its characteristics (Paneque et al., 1996 a). Human action together with other Elements and Agents involved in the vine growing production (Reyner, 1989) over these means lead to agronomic systems with important characteristics. Finally, the transformation of the vine growing production, through different technologies (Fleet, 1992), results in the creation of products with a different acceptance and economical value in the market.

Aims: The aims of the present study were to (1) evaluate the water dynamics of Touriga-Nacional grapevines trained to spur pruned cordon and Guyot systems and (2) assess the effect of variable water availability in a commercial vineyard located in the Demarcated Douro Region (DDR), Portugal.