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The science of description and identification of the vine species Vitis and its cultivated vine varieties. A volume of vine descriptions is also called an ampelography, the word coming from the Greek ampelos for vine, and graphe for writing. Some system of distinguishing between grapevine varieties is clearly necessary since the early French ampelographers Viala and Vermorel (see below) were able to list about 24,000 names of varieties and their synonyms in their seven-volume Ampelographie published between 1902 and 1910. Some system of vine identification is particularly necessary in the modern era of varietal wines (see below for examples of mistaken identification, especially in the New World).
There has long been an awareness of differences between vine varieties, and Pliny the Elder could already produce vine descriptions and state that synonyms were creating confusion in Ancient Rome. While regional ampelographies emphasizing the aptitudes of various cultivated varieties already existed in medieval Europe, it was not until the second half of the 19th century that a need for more systematic study developed. When serious vine diseases and pests were introduced to Europe from America (powdery mildew in 1852, phylloxera in 1863, downy mildew in 1878, and black rot in 1885), it became essential to identify those species and varieties which showed most resistance to these hazards. Such species were soon used for vine breeding and as rootstocks. Early ampelographic works emphasized fruit characters, and did not provide a key for classification, so that it was impossible to determine the name of a variety in a systematic fashion. Further, the distinguishing features of the vine varieties themselves were not emphasized. The vegetative parts of the vine were not used for identification since they were thought too variable and not stable. The Austrian ampelographer Hermann Goethe proposed measuring the angle between leaf veins as an identifying character in 1876, and this concept was developed by the French ampelographer Louis Ravaz when in 1902 he published his, presumably much-needed, book Les Vignes americaines. Several large regional ampelographies were published near the turn of the century, including Pulliat (1888) and also Viala and Vermorel (1902-10) in France; Goethe (1878) in Austria; Rovasenda (1881) and Molon (1906) in Italy; and Hedrick (1908) and munson (1909) in the USA. The most famous modern ampelographer, Professor Pierre Galet of Montpellier, began his studies in 1944 by inspecting rootstock plantings, and this led to the publication of a distinguishing key in 1946. These studies were extended to include wine and table grape varieties and in 1952 his Precis d'ampelographie pratique was published, followed by, among other works, Cepages et vignobles de France. Galet formalized the study of the morphology of the growing shoot tips, leaves, and shoots, including qualitative descriptions of leaf hair types and quantitative descriptions of leaf shape. Vine characteristics which ampelographers use to differentiate species and varieties include colour and hairiness of shoot, shoot tip, petiole, and young and mature leaves; the shape, contour, texture, and indentation of leaves; the sex of flowers; shape and compactness of bunches; and shape, colour, taste, and seed presence of grapes. These characteristics are more or less subjective but once an observer becomes familiar with the terminology they are easy to use. Grape flavour is admittedly subjective, but at the other end of the scale of objectivity is Galet's comprehensive quantitative description of leaf shape by measuring the lengths and angles of the veins, the ratio of length to width, and the depth of sinuses. Other characters have been considered for identification, including the timing of phenological or development stages such as budbreak, fruit maturation, or even leaf fall. Such features are known to be controlled by the environment, however, and can be used only in a relative sense for vine varieties in a single region. The disadvantages of the technique are that, while some characteristics are quite stable, others, such as leaf shape, can vary markedly even on one vine. Major differences can be caused by environmental factors, but also and to a lesser degree by variation between different clones, plant age, and the influence of pests and vine diseases. There are, however, five characters which are quite stable: sex of the flower; grape skin colour; pulp colour; the taste of berries; and the presence of seeds. Experience has shown that ampelography is a field of systematic botany requiring very specialized skills and interpretative ability, as well as an extraordinary memory. There are very few people who can walk into any vineyard and unequivocally identify varieties. Some modern acknowledged experts apart from Pierre Galet include his colleague Paul Truel and successor Jean-Michel Boursiquot of Montpellier, and the late Alan Antcliff of Australia. A complex ampelographic procedure was proposed by the Office International de la Vigne et du Vin (OIV) in 1951, based on 65 morphological characters. The International Board of Plant Genetic Resources (IBPGR) and l'Union International pour la Protection des Obtentions Vegetales (UPOV) have also produced lists of descriptors and all three international systems have been harmonized by the introduction of numeric codes. Ampelographic studies have recently been facilitated by application of computers and electronic data storage and retrieval, but final identification still relies heavily on the judgement of ampelographers. Blind tasting tests on varietal wines have demonstrated that the human palate does not reliably identify different vine varieties. More recently, attempts have been made to develop objective, laboratory-based tests for vine identification, including isozyme analysis and gel electrophoresis of enzyme banding patterns. The most recent are DNA `fingerprinting' methods. Unfortunately, mistakes in naming grapevine varieties are common, especially in the New World, in government collections as well as in commercial nurseries and thus vineyards. Some of the early introductions of vine cuttings to these regions were made before European vine-growers had correctly identified their own varieties. Sometimes name tags on bundles of vine cuttings, all of which look remarkably similar, were simply misplaced or transposed. In other cases, confusion was caused by different synonyms in different European regions. James Busby's celebrated vine collection introduced to colonial Australia in 1832, for example, probably contained Cinsaut cuttings under seven different regional synonyms, and Chenin Blanc under three. The noted French ampelographer Paul Truel studied a large collection of French varieties at Vassal on the Mediterranean coast in the 1960s and 1970s and found that as many as six distinct varieties grown in different parts of France were a single variety under different names, and there is even more variation in nomenclature between countries. The Graciano of Spain, for example, is the same as France's Morrastel while the Ottavianello of Italy is the same as Cinsaut of France, but more complex examples abound. Because its nursery has been able to provide virus-free, high-health vines, the University of California at Davis has been an important source of varieties for many establishing New World countries. Naming mistakes in this collection are legion, and have caused inconvenience for both the California wine industry and importers of plant material from Davis. Some examples of such errors cited in California by French ampelographers Galet and Boursiquot, in Australia by Truel, and in New Zealand by Zuur include Abouriou (incorrectly called Early Burgundy), Petit Verdot (Gros Manseng), one clone of Pinot Noir (Gamay Beaujolais), Negrette (Pinot St George), Valdiguie (Napa Gamay), Melon (Pinot Blanc), Muscadelle (Sauvignon Vert), Tempranillo (Valdepenas), a clone of Sauvignon Blanc (Savagnin Musque), Trousseau Gris (Grey Riesling), and Touriga (Alvarelhao). Generally rootstocks are more difficult to differentiate as they do not often fruit, so it is not surprising that problems have also occurred with their naming. In the 1990s California growers were forced to replace the rootstock AXR1 as it succumbed to phylloxera. This replanting effort was thwarted by finding that the rootstock thought to be SO4 was in fact 5C Teleki, and Riparia Gloire was mixed with Couderc 1616. Since the early 1970s many countries have recognized these problems and have attempted to reduce the confusion. Invalid synonyms are discouraged, as is incorrect naming. Problems inevitably arise, however, when incorrect names become established commercially (see Sauvignon and Merlot in Chile, for example). Bibliography - Galet, P., Cepages et vignobles de France (2nd edn., Montpellier, 1990).
- Galet, P., and Morton, L. T., A Practical Ampelography (Ithaca, NY, and London, 1979).
- Huglin, P., Biologie et ecologie de la vigne (Paris, 1986).
References black rot budbreak Chile Cinsaut clone Davis DNA `fingerprinting' downy mildew leaf fall New World phylloxera Pliny powdery mildew rootstock varietal vine breeding vine varieties Vitis
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