Análisis of the intervarietal heterogeneity in the Vine Germplasm of La Rioja (Spain).

Resumen

The progressive decrease of the genetic diversity of plants is called genetic erosion. This problem also threatens Vitis vinifera. The genetic resources preservation is justified by the need of protecting varieties in danger of extinction, genes with a present or future agronomic interest, and variability in cultural aptitudes and organoleptic complexity. A project of genetic resources of Vitis vinifera preservation in la Rioja (Spain) made possible the creation of a germplasm bank. It contains fifty-four varieties, which have been characterized by ampelographic, phenologic and ripening studies. This bank represents the greatest collection of vine genetic resources in la Rioja. The aim of the current study is to analyse the variability of the germplasm bank of la Rioja. We have compared it with the bank from Domaine de Vassal (France), which represents the greater worldwide variability. For each variety, it has been studied (2000-2003) the following characters: sex of flower, color of skin, color of flesh, presence, width and length of seed, ratio W/L of seed, shape of berry, ratio L/W of berry, fertility and average weight of berry and bunch. At the same time, it has been studied the phenology of each variety: bud burst, blooming, veraison and ripening, as well as the blooming-veraison period. This study has shown that the germplasm bank of la Rioja (Spain) represents an important source of variability, which is very interesting for the support of the genetic resources.