The consequences of the phylloxera epidemic that nearly wiped out wine in the way we think of it, is still felt to this day. Jamie Goode introduces the 19th century epidemic that was caused by a tiny yellow Aphid.
Biosecurity is a hot topic nowadays. If you get off a long-haul flight carrying one of your apples in your baggage and be hit with a huge fine if you fail to remove it prior to completing the customs. In the 19th century, however it was never a thing. Plants were moved – along with them , diseases and pests all over the world.
It was the deficiency of understanding of the importance of biosecurity, and the advent of steamships which almost resulted in the end from wine in the way we recognize it today. What was the significance of the steamship? It meant that plants that were transported between one place to the next could arrive in a hurry so that any pests that were brought along have a better chances of surviving the trip.
Enter phylloxera. This aphid feeds on the vine’s roots which originate in North America. It is dependent on the type of vine and location it may also be found feeding on leaf. In this case, it coevolved with native vines, and both grew next to one another without much difficulty. The best parasites do not kill their hosts, because after all, they have to find a place to stay. They do take a small amount and less than. However, Vitis vinifera is the Eurasian grapevine species that makes up most wine that is produced around the world, has developed without the help of this aphid. when the two species came together, it was a conflict which led to the demise of this vine.
How did phylloxera make its way into Europe and, from there, across the globe? It’s all in a different disease that struck the world of wine that was powdery mildew. This was also a problem in the USA which arrived around the year 1850. Also the native American vines are resistant to this fungal disease however when it came to Europe, Vitis vinifera was extremely vulnerable. One solution suggested was to grow resistant American vines, and they were sent to Europe. They brought along the phylloxera.
The first outbreaks were reported in the 1850s in Southern Rhone and the Douro followed by a few months later in Austria. From the beginning it was a rapid spread and the final quarter in the late 19th century witnessed the spread of phylloxera across the wine-growing world leaving behind an economic trail of destruction.
Genetic studies of the present have demonstrated that there could have been two distinct instances of phylloxera which then expanded to all parts of the world of wine. The first, and the most well-documented case – occurred in southern France The second occurred in the nursery of Austria. At the time that people were aware of what was happening the affected plant material had already been widely distributed across these two areas by viticulturists seeking solutions to powdery mildew.
The life-cycle that this bug goes through is complex However, the damage it causes is very serious. As it pulls the poop from root system that is not protected the vascular system of the plant is affected and they stop functioning. The vine starts to decline that will result within a couple of seasons in the death of the vine. It is also believed that the damage to the feed makes the roots more susceptible to infection, which speeds up the end of the vine.
It’s difficult to imagine the rage that would have been experienced during the time of wine-producing countries like France in which this beverage was a major part of culture and economy. At the time, about one-sixth of France’s revenue was made by wine and one third of the workforce earned income from it.
It was the responsibility of Prof. Jules-Emile Planchon, a botanist selected by the government commission set up to study the outbreak, to determine the source of the problem. He excavated the branches of the healthy plant and observed clumps and clumps insects with no wings happily eating their way through.
Phylloxera has a long and complex life-cycle, which was discovered only after the disease had ended. As with many aphids is parthenogenetic. This means that it doesn’t require sex in order to reproduce. The form that grows roots settles on the appropriate roots and then punctures them using its mouthparts. It injects saliva which results in the roots cells to expand into a structure called galls, which increase the amount of nutrients available and also provides protection. Then , it lay eggs that hatch, and the winged forms of the aphids move along the roots, ascends the tree and is carried out into the air. If they can find the right place to feed, they’ll continue to multiply and populations will grow quickly. In certain regions, there are sexual forms of phylloxera, which develop on leaves. They can also cause gall formation and in this instance the protective structure that surrounds the feeding phylloxera is extended below the leaf and extends towards the leaf’s upper surface, allowing crawlers to escape.
A variety of options were explored. Chemical defences were attempted but generally did not work (a horrible insecticide known as carbon bisulfide showed some effects when injecting into the roots, however it was only a small amount) Flooding vineyards during the dormant season proved to be effective; the vines in sandy soils did not seem to be affected. However, for the majority of vineyards not in sandy soils and couldn’t be flooded there was no hope.
A controversial solution was suggested. American vines that harbored the invaders in the first place was naturally protected from the phylloxera. In the areas where they were planted, they flourished, and everywhere else was the scene of destruction. Sure, the wines produced was not very good, but it was better than none even if it was not, said the side that supported this method which was later referred to as the americanists. Wine tastings made with the American vinifera varieties were arranged however the sad conclusion was that the vinos, with their unique flavors, did not compare with the wines that people were used to drinking from vinifera varieties.
What do you think about crossings between American vinifera and vine species? Could these crossbreeds blend the strength of the vinifera with the resistance of the vinifera? This was the subject of the course of a series of breeding experiments which led to what are today referred to as the hybrids of French and American. A few of them are quite interesting, however they differ with respect to their resistance against phylloxera and didn’t really take off to the public. It was nevertheless an extremely interesting time for breeding vines.
In the following year, someone came up with an idea that was brilliant. The year was 1869 and man named Gaston Bazille suggested grafting vinifera varieties onto American rootstock. With retrospect, this is an ideal solution, however at the time, there were many unanswered questions. Most important among them were the following. First, how long will the graft be in place? Then, will the rootstock bring the American vinifera character to the wines, altering characteristics of the vinifera variety through the unnatural union of stock and scion? Thirdly what is the degree of resistance different rootstocks be? We already knew that certain American plants were less tolerant to the phylloxera, compared to other varieties.
A first time that we have documented examples of this technique was in 1874 at the time that Henri Bouschet displayed an Aramon (Vitis vinifera) vine that was grafted onto an American rootstocks at the Congres Viticole at Montpellier. After a brief period, it was apparent that, albeit in a strange way the wine produced by vinifera vines grafted on American rootstocks had the entire character of the vinifera grape while benefitting from the phylloxera-resistant qualities that is characteristic of American roots. It was the perfect circle. The disease had originated in America and was averted, but so too had the hope for salvation.
The concept spread. The process of grafting was so simple to master that almost anybody could try it. The availability of American vines became more problematic as many wineries were beginning to ban imports to keep the remaining vineyards that were phylloxera-free from falling victim to the disease. But not all were attracted by the radical concept of transplanting. Some were against replanting, and the consequent loss of three years of production. They clung with fervor to their chemical treatments. At the end of the day, common reason prevailed and the grafters took the day. The lengthy work of replanting phylloxera-devastated vineyards began. It was not an easy process, and some the most prestigious estates, unwilling to remove their vineyards, continued to treat them by applying insecticides as lengthy as it was possible. The selection of the right material for grafting was further complicated due to being unable to time to locate American vine varieties which were well-adapted for the clay soils that prevailed in a few of France’s major regions.
The repercussions of the phylloxera epidemic remain in the present. The most significant impact was the alteration of the landscape of viticulture. If we take France for an instance, vineyards decreased quite dramatically. Replanting also led to the fact it was form of viticultural bottle neck with traditional varieties being wiped out and being discarded to be replaced by more interesting varieties that are commercially appealing. There are many regions where there are efforts to reintroduce the ‘lost’ varieties which were able to disappear in this replanting phase.The replanting process is a long and tedious one. One of the most traditional methods of planting vineyardsis marcottage or layering, involves placing a cane that is still attached into the soil so that it develops its own roots, relying on the mother vine until it eventually becomes a distinct vine that is its own is no longer an appropriate choice. The reason is that the roots are vinifera, and therefore susceptible to phytolloxera. Prior to the crisis there were many vineyards that were planted in foule – basically randomly, without rows due to the continual lay-down of canes, and even the trunks renewing the vineyards without planting. After the crisis, the majority of wineries were planted with rows.
Additionally, the selection of rootstock, and its impact on the factors affecting grafts, including vigor, was added as an additional variable, and an entirely new feature in the toolbox of viticulture.
Certain areas have been spared from the phylloxera plague, and in these areas is still a variety of plants that have been planted in their roots. The most famous include Chile as well as South Australia, which have been able to stay free of the disease. Argentina along with Washington State also have largely ungrafted vineyards. While the phylloxera virus is prevalent in both, it does not appear to be a significant issue. This could be due to the soil’s structure, and in the case of Argentina, some have suggested that it’s due to the fact that much of the irrigation is done through regular flooding. Within Germany’s Mosel wine region, there are many vineyards ungrafted (again the soil appears to protect) as well as the Douro has a renowned vineyard that is planted on its root: Quinta Do Noval’s Nacional. The the New Zealand’s Central Otago wine region the oldest vineyards in the region that date from the 1980s are not grafted (some have succumbed, unfortunately) as well as many of Oregon’s oldest vineyards are growing on the roots of their owners (likewise that they’re in a state of decline).
For the last 130 odd years, there’s been a cease-fire. By grafting onto American rootstocks we can have wine, which is still in a way, like it was. Both the roots as well as aphids coexist together in a certain equilibrium. What is the outlook for the future? What happens in the event that this balance becomes unstable, and a new form of phylloxera is developed which kills the vine? The idea is impossible.
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