Research conducted at El Encín, Spain's largest collection of grape varieties, has established that there are 235 different grape varieties, both for vinification and consumption.
Knowing the origin and evolution of the vines is a very complex task which faces major historical omissions. There is information about ancient viticulture practices as well as the style of wines that used to be made in the past. That is not the case for vine varieties, which have greatly evolved and changed throughout time.
Ampelography is the science devoted to describe and identify vine varieties. Certain features and characteristics allow their identification: the shape of leaves, bunches and grapes; fruit colour; oenelogical features (sugar and acidity content, phenological composition and aromas) and agronomic conditions (vigour, fertility, yields, maturation times, disease resistance).
In his Tratado de Viticultura (Viticulture Treatise) written in 1993, Spanish agricultural engineer and vine expert Luis Hidalgo calculated that the number of grape varieties ranged between 10,000 and 20,000; new research published by Patrice This in Trends in Genetics in 2006 narrow this figure down to 5,000. Ancient and new migratory movements, along with trade exchanges have helped well-known varieties to thrive in all corners of the world. The problem occurs when various names are used to distinguish a unique variety growning in different areas. The result is a high number of synonyms or worse still, in the use of a popular grape name to refer to radically different varieties, creating a homonym.
The birth of ampelography dates back to 1611 when French agronomist Olivier de Serres tried to shed some light into this complex puzzle. He mentions several French varieties' names, but it was not until the end of the 19th century when the first significant studies where carried out which culminated in 1910 with the publication of Viala and Vermorel's monumental treatise collecting 24,000 grape varieties.
The study of varieties was greatly boosted in the 1970s and 1980s by the popularity of varietal wines that swept across the New World, specially in Australia and America. This trend increased the interest for varieties and had also an effect in Europe.
Nowadays new technology has greatly helped ampelography: computer-analysed images, molecular identifications based on DNA profiling and the posibility to compare information among various specialist centres. Countless homonyms and synonyms are being resolved helping to uncover the origin and distribution of varieties which currently grow in our vineyards.
Spain's Register of Commercial Vine Varieties is the reference point where all known grapes varieties are found along with their names and authorised synonyms. The list includes 215 varieties divided in two groups: a definitive list and a provisional one. The first list includes 86 varieties, with 15 of them being table grapes, 4 are apt for both and the rest are used for vinification. This last group may be waiting to complete its characterisation process or a comparison study with other names (MAPA Wine Register, 2012).
All the appelations of origin publish a list of authorised and preferential varieties which must be used to produce wines in their catchment areas. In total, there are 1,040 references, including both varieties and appellations. Cabernet Sauvignon, which was a popular foreign variety in 1990s, is authorised in 48 appellations. Tempranillo, which is the most planted red variety in Spain, is present in 56 Denominations of Origin.
Research of 870 traditional vine varieties conducted at El Encín has shown that only 235 of them -both table and vinification grapes- are currently planted in Spain. Out of this number, 111 are native varieties suitable to make wine in the country's 70+ Denominations of Origin. There are five varieties included in the Commercial Varieties Registry which are not present in any appellation; 74 are a minority crop or in danger of extinction; 19 authorised foreign varieties, mostly originating from France and Germany and 26 traditional grapes.