New grapes on the block: Varieties to watch

New wine grapes are being created all over the world, but with thousands already out there, why do we need more? Maggie Rosen explores efforts to build a better grapevine..

Aromella, Mystique, Divico and Floréal may sound like distant galaxies or characters from Game of Thrones, but in fact they are among the newest wine grapes available to winemakers.

Right now, in agricultural research stations and experimental vineyards around the world, hundreds of grapes are somewhere on the complex journey from bright idea to bottle.

The few that make it beyond the creator’s scratch-pad must be rigorously monitored through multiple harvests and micro-vinifications; cleared by regulatory and industry bodies; and above all, accepted by producers – well before they can be bottled for sale.

This process can take decades. Given the competition from thousands of established varieties, it’s a wonder that anyone tries. But man has always sought to perfect nature, for both practical and personal reasons – and grapes are no exception.

‘I find it fascinating to try to create new varieties,’ says Dr José Vouillamoz, grape geneticist and co-author of Wine Grapes. ‘But I doubt anyone does this for the beauty of it. Most breeders are trying to solve a problem – to reduce the need for chemicals or grow vines in places with extreme weather.’

Grape-scape: a potted history

Left alone for millennia to develop and adapt, most grapes are the result of spontaneous Vitis vinifera crosses. But following Europe’s phylloxera outbreak, the tradition of allowing several varieties to grow in one vineyard was eliminated. Scrambling to resurrect their livelihoods, growers grafted disease-free components, methodically separated into varietal parcels. Machines and chemicals have prevented the kind of uninhibited assignations that in the past produced a love-child like Chardonnay (Pinot Blanc, Gris or Noir x Gouais Blanc).

In with the new

Australia’s Brown Brothers has long embraced the new. In 1980, it launched Tarrango (a cross between Touriga Nacional and another Vitis vinifera, the white Sultana) – now its top-selling wine in Europe – followed in 2000 by Cienna (Sumoll x Cabernet Sauvignon), its most successful wine overall.

Both these and the company’s newest, Mystique, which was released in 2017, were developed to produce balanced, quality wine despite extremely hot and dry conditions. With fresh-picked black- and blueberry flavours, and only 12.5% alcohol, Mystique is light for the Murray Valley climate. ‘We were attracted to Mystique because of the amazing colour intensity for a red wine grown at warmer sites,’ says Joel Tilbrook, chief winemaker. ‘It is many times that of Shiraz or Cabernet Sauvignon.’

Brown Brothers is testing six other new grapes, as yet unnamed. Over the years, it has trialled – and rejected – dozens more. As a family company, it can afford to experiment and change direction quickly if unsuccessful.

Mystique’s lineage remains confidential, pending publication by its developer, Australia’s Commonwealth Scientific and Industrial Research Organisation.

Other key national breeding programmes include Switzerland’s Agrosocope, and Germany’s Geisenheim and Julius Kühn (Geilweilerhof) institutes. In the US, Cornell, the University of Minnesota and University of California Davis, funded by federal grants and industry endowments, are among the leaders.

Historically, all have concentrated on local challenges – such as extreme temperatures or an unstable water supply – to match fruit to terroir. Many new varieties belong to the so-called PIWIs, a group of hundreds of grapes bred to resist fungal diseases and therefore requiring less chemical intervention.

At UC Davis, Professor Andrew Walker has dedicated his 30-year career to Pierce’s disease – the vine-killing bacterium Xylella fastidiosa, borne by leaf-hopping sharpshooter bugs. Pierce’s, which also affects produce such as citrus, almonds and olives, thrives in hot conditions. As extreme heat and drought become more common, his grapes – five due for imminent release and 19 in the wings – will, Walker is confident, prove useful to growers and appealing to consumers.

Nobody expects these to unseat the behemoth Cabernet Sauvignon (the world’s most-planted grape, covering 290,000ha worldwide and 75% of vineyards in China). But they will be in demand because they are uniquely resistant to Pierce’s.

‘These are breakthroughs from the perspective that we’ll be able to make better wine in problem areas and grow grapes where you couldn’t before,’ says Walker. ‘Growers in Texas, Alabama, Georgia and Mexico – and of course hotspots in California – are very excited.’

Cabernet Sauvignon’s parents (Cabernet Franc x Sauvignon Blanc) were confirmed at UC Davis in 1997 using new DNA profiling techniques. These led to marker-assisted selection, which today allows breeders to follow a ‘trail of interest’ (such as improved productivity or tolerance of stress) by extracting and testing DNA for indications of desired traits, which can in turn be encouraged in the next generation.

Walker purposely sought parents (Vitis vinifera with a small percentage of Pierce’s resistant non-vinifera species) with characteristics that could, via blending, enable winemakers to comply comfortably with the state’s 75% threshold for single-varietal labelling.

‘We thought we’d choose the top 10 international varieties and try to make something resembling those,’ he says. ‘We have some Sauvignon Blanc-like material, some Pinot-like material, some Zinfandel-like material – not of course those specific varieties – and people who have tried the small vinified batches have been impressed.’

Signs of success

New York’s Cornell University has released dozens of cold-hardy, fungal disease-resistant, interspecific wine grapes since the 1800s. Cayuga White (1972, Schuyler x Seyval Blanc) and Traminette (1996, Joannes Seyve 23.416 x Gewürztraminer) are among the most successful, and though not household names, are significant to northeastern and mid-western states of the US.

Determining the success of a new grape is not a simple sales-based evaluation. Breeders try to keep track of the number of vines by consulting censuses, but these are not always current. They also monitor wine labels that disclose the components of a blend, and note competition award-winners.

Since 1980, Professor Bruce Reisch has overseen the release of 10 Cornell grapes, including the newest, a white grape called Aromella (2013, Traminette x Ravat 34) – and dozens more are in progress. ‘This makes beautiful wine,’ he says, ‘very aromatic, with good balance. Modern gene editing has also sped up the process of mitigating undesirable attributes – such as the “foxy” flavours present in American and Asian (non-vinifera) species – which some tasters find off-putting.

‘Our challenge is to figure out as early as possible which seedling has the most genes for the traits we want, and these tools help to speed up that process,’ continues Reisch. ‘Resistance may be one of our goals, but if it doesn’t make good wine, forget it.’

His wish list contains a suite of markers that are not yet available. ‘We’d love to identify the attributes that go along with Riesling or Merlot. The more quality characteristics we can identify at an early stage, the better we can focus our efforts and somewhat shorten the time it takes to release new varieties.’

It’s not just the New World that’s fruitforward in this respect. Switzerland and Germany have been creating grapes for years; consider Müller-Thurgau (1882, Riesling x Madeleine Royale), Scheurebe (1916, probably Riesling x Bouquet Blanc) and South Africa’s Pinotage (1925, Pinot Noir x Cinsaut).

Even conservative France, which banned propagation of most non-vinifera grapes in 1935, has recently launched four: Floréal and Voltis (white), Vidoc and Artaban (red).

‘One important issue is that EU regulations only authorise pure vinifera for the appellations,’ notes Laurent Audeguin, who oversees breeding programmes for the Institut Français de la Vigne et du Vin. ‘In my opinion, this regulation will evolve.’

Vine-breeding keywords

Cross-intraspecific When one variety of Vitis vinifera (the native Mediterranean species, source of ‘Old World’ fine wine grapes as opposed to table grapes) is combined with another Vitis vinifera via sexual reproduction. The pollen of the first fertilises the flower of the second. The four seeds of the resulting fruit are the offspring, each of which can create a new Vitis vinifera. Parentage is expressed as Grape A x Grape B (ie, Malbec’s parents are Magdeleine Noire des Charentes x Prunelard).

Hybrid This is also a cross but an ‘interspecific’ one, between a Vitis vinifera species and a non-vinifera one, such as Vitis labrusca or Vitis riparia.

Clone The creation of a plant with the same genetic material as another, via asexual reproduction: a piece of one vine is either grafted or planted directly in soil. The first generation will be identical to the ‘mother’, but as the plant mutates over time and adapts to different conditions, it will develop new characteristics that, if welcome, will be encouraged by the producer. This is why Syrah (Dureza x Mondeuse Blanche) from California is different to that of the Rhône.

Maggie Rosen writes about wine for English- and French-language trade and consumer publications, and helped to launch Coravin in the UK

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