When you visit the vineyards of Beaujolais, the chances are that you expect to see vineyards populated with rows of gamay vines. Odds on you’d be right (with the slight caveat that around 5% of the region is planted with chardonnay). All these stats are what makes the Sicarex experimental vineyard in southern Beaujolais so unusual. There’s gamay planted here, of course, but each row features a different clone of the grape. Other rows are planted with different grapes, well-known in their home regions, but less so in this particular location – you’ll find gewurztraminer, auxerrois and roussanne, as well as merlot and syrah. And then things get a bit weird, with crosses, varieties like marselan, gamaret, picarlat and peaugaray, ripening gently in the warm summer sunshine. There are no hybrids planted in this particular vineyard, but they’re increasingly common in other regions and in other countries, where viticulturists and viticultural scientists are doing due diligence in researching varieties that may be better adapted to our mid-term-future. The clones, crosses and hybrids they’re planting are of increasing interest to grape growers around the world, for a variety of reasons, not least for their potential to help future-proof vineyards against climate change and to reduce the need for treatments of all kinds.
Clones
Clones are, perhaps, familiar to anyone who’s ever studied botany or viticulture (or, for that matter, anyone who’s ever seen a Star Wars movie). Grape varieties aren’t always consistent in their genetic make up, and gene variation within a species gives rise to different expressions of that variety. Among the numerous pinot noir clones available to growers, 777, is widely planted in both the Old and New World by producers seeking to make high-quality wines because it gives small bunches and berries, characteristics that give rise to wines of intense colour and structure (in the context of pinot), as well as typically spicy aromas. Move two numbers along, though, to number 779, and you find a higher-yielding clone that is more typically planted in Champagne (and other sparkling wine regions), where its relative lack of structure creates a more neutral platform for the winemaking processes to come.
It's not just pinot noir, of course, that comes in clonal ‘flavours’. Whether you’re planting shiraz or chardonnay, the selection of clonal material is an important decision. Unless, of course, you’re planting a massal selection rather than a clonal selection. In massal selections, rather than populating a vineyard with a single clone, growers take cuttings – often from older vineyards – in order to propagate new vines that share the diverse characteristics of their ancestors. If done carefully, by selecting the best vines from which to propagate your new vines, massal selection is a way of preserving genetic variation, ensuring that vineyards have greater resistance to disease and, potentially, are better adapted to the challenges imposed by ever more variable climatic conditions.
In theory, too, the diversity of massal selection may help your terroir express greater complexity than clonal selection can. However, massal selection carries its own risks; by planting selected clones, you can be sure that they are virus-free and resistant to certain kinds of pathogens. Some producers are now attempting to create the best of both worlds by planting their vineyards with a selection of different clones, sometimes interspersing them with vines sourced by massal selection.
Back to that vineyard in Beaujolais. Some of the gamay clones being trialled are being assessed for their ability to maintain high levels of acidity in hot, dry growing conditions, or for their propensity to ripen later at lower must weights, helping to keep alcohol levels from spiralling out of control. By planting appropriate clones – or a selection of clones – growers hope to be better placed to meet the challenges increasingly being imposed by rising summer temperatures.
Crosses and hybrids
Varietal clones are a fairly subtle way of introducing diversity into the Vitis gene pool. If you wanted, you could think of clones as being a bit like snowflakes in that snowflakes all look a bit different, but are all essentially snowflakes. Things get a bit more dramatic when you start looking at crosses.
The term is used to refer specifically to new varieties created by the interbreeding of two varieties of the same species, which in the context of wine grapes is generally Vitis vinifera. The origins of most of our best-known grapes lie in such crossings. chardonnay, for instance, is the offspring of pinot noir and gouais blanc – although proof of its ancestry lies in DNA analysis rather than contemporary records. A more recent cross that’s become well established – at least in South Africa – is pinotage, whose parents pinot noir (clearly a grape that gets around a bit) and cinsault got together in the 1920s. Marselan, the offspring of cabernet sauvignon and grenache, was born in the 1960s, but only began its rise to prominence in the vineyards of the Languedoc and China at the tail end of the 20th century, largely thanks to its resistance to powdery mildew. (Hold that last thought for a couple of paragraphs, by the way.)
Hybrids, on the other hand, are what you get when two different Vitis species get jiggy with each other. Typically one of the parents is a Vitis vinifera vine, while the other parent while be a Vitis species native to the Americas or Asia, such as Vitis amurensis or Vitis labrusca. The idea is that the offspring of such a cross will show what is known as ‘hybrid vigour’, improved traits that leave it more resistant to disease or extremes of climate. The use of the term hybrid for varieties such as sauvignac, souvignier gris and regent, although easily understood, is falling out of favour, tainted perhaps by connotations of Victorian-era racism. Instead these vines are increasingly referred to as PIWI varieties. The contraction is understandable when you realise the name is derived from a German term, ‘Pilzwiderstandsfähige Reben’, which can be roughly translated to mean ‘fungus-resistant’.
Fungal resistance is one of the key characteristics viticulturists are looking for when they plant crosses and PIWIs. In an era when changing weather patterns are putting vineyards under increasing pressure from fungal diseases, the ability to minimise the risk of infection without having recourse to anti-fungal sprays is an attractive one for anyone seeking a sustainable solution. But the sustainability of such grapes doesn’t stop short at their ability to lessen dependence on treatments – hidden environmental costs like the carbon footprint of regular tractor use and the compaction of the soil that follows on from the use of heavy machinery in the vineyards are considerations too. Furthermore, some crosses and PIWIs are better adapted to surviving in extreme weather conditions than better-known varietals. Frontenac, a black PIWI, is cold-hardy as well as being highly resistant to downy mildew, as is solaris, a white grape that is grown as far north as Scandinavia, while marselan’s late-ripening tendencies make it a useful variety to plant in warmer climates.
Given the increasing concerns about sustainability, the need for grapes to combat both fungal diseases and illnesses caused by other organisms, as well as an increasingly temperamental climate, there’s a strong possibility that grapes like gamaret and vidal blanc will become as recognisable to the wine lovers of the future as sauvignon blanc and nebbiolo are today.