A work involving the finding, the description and the recovery of old grapevine varieties from the north and north east of Spain was begun in the CSIC in the year 1987. Among the red varieties that were found, the Verdejo Negro stood out because of its high quality. Different previous works (Martínez and Pérez 1999, 2000; Martínez et al. 2004, Santiago et al, 2003) have allowed us to know this cultivar from the ampelographic, agronomic and molecular point of view.
The aim of this study was to compare the agronomic behaviour of Verdejo Negro in two different climate areas from North Spain: one from a mountain viticulture area and other from a coastal one. In each of these areas we have an experimental plot. The first one is placed in western south of Asturias region; it is located in the slope of a mountain and has an altitude of about 506 meters with a strong slope; the geological base of the soil is formed basically by shale, sandstone and quartzite. The stocks were planted in 1991. The second plot is located in the south of Galicia region, near from the Atlantic coast, in an area without slope and with an altitude of about 35 meters. The geological bases of the soil are glandular orthogneis. The stocks were planted in 1993. In both cases the plants are grown en espalier, but pruning methodology is different and adapted to the conditions of the two areas studied. In the mountain plot pruning is made using a Guyot system and in the littoral one the Sylvoz system is used.
During four years (2002, 2005, 2006 and 2007) several agronomic parameters were measured such as the fertility rate, weight, length and width of bunches, probable alcoholic grade, must yield, pH and total acidity of the must.
The results showed that for some parameters, such as probable alcoholic grade and pH, there were no significant differences between plots, but for other parameters, as for example fertility rate, grape production per plant, must yield and total acidity, significant differences were found.
Authors: MARTÍNEZ M.C.; GAGO P.; BOSO S.; ALONSO-VILLAVERDE V. and SANTIAGO J.L.
Misión Biológica de Galicia (CSIC), Apartado correos 28, 36080 Pontevedra, España
Email: carmenmartinez@mbg.cesga.es
Keywords: agronomic characterization, Verdejo Negro, littoral area, mountainous area