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What Is Phylloxera and How Did it Effect Wine?

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The consequences of the phylloxera epidemic which nearly destroyed wine in the way we think of it, is still felt to this day. Jamie Goode introduces the history of phylloxera – 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 bag and be hit with a substantial penalty if you don’t take it out before you get to the border. In the 19th century, however the apple was not a thing. Plants were moved – along associated diseases and pests all over the world.

It was the inadequacy of awareness of the significance of biosecurity, and the introduction of the steamship 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 across continents from one to the next could arrive in a hurry so that any pests associated with them would have a greater chances of surviving the voyage.

Enter phylloxera. This aphid feeds on the vine’s roots which originate in North America. It is dependent on the type of vine and the area it is also able to consume leaves. In this case, it coevolved with native vines, and both grew next to each other without many issues. A good parasite doesn’t kill its hosts. After all, they require a place to stay. They do take a small amount however, very little. However, Vitis vinifera is the Eurasian grape vine that makes up the majority of wine produced around the world, has developed without the help of this aphid. when the two species came together, it resulted in an imbalance which resulted in the death from the grapevine.

How did phylloxera make its way into Europe and, from there, across the globe? This is the answer in a different illness that has shaken the wine industry that was powdery mildew. This was also a problem in the USA which arrived around the year 1850. Also is where 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 transported to Europe. They also brought the phylloxera.

The first outbreaks were reported in the 1850s in Southern Rhone and the Douro followed by a few months later in Austria. Since the first outbreaks it was a rapid spread and the final quarter into the nineteenth century witnessed the spread of phylloxera throughout the wine-growing world leaving behind the trail of economic destruction.

Genetic studies of the present have demonstrated that there could have been two distinct outbreaks of phylloxera , which later expanded to all parts of the world of wine. The first, and the most extensively documented case was in southern France The second occurred in an agricultural nursery in 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 searching for an effective treatment for powdery mildew.

The life-cycle for this bug is complex However, the damage it causes is very significant. As it pulls the poop from unprotected roots the vascular system of the plant is affected and they stop functioning. The vine then begins to decline that will result after a few years of dying. It’s also believed that the feeding injury exposes the roots to infections, which accelerates the demise of the vine.

It’s hard to imagine the fear that would have been experienced during the time of wine-producing countries like France in which this beverage was an integral part of the culture and economy. At the time, about one-sixth of the French state’s revenues were made by wine and one third of the workforce earned income from it.

It was the responsibility of the professor Jules-Emile Planchon, a botanist selected by the commission of the government to study the outbreak, to pinpoint the cause. He excavated the rootstocks of an energizing plant and observed tiny clumps of insects with no wings happily eating their way through.

Phylloxera is a complex life-cycle, which was discovered only after the plague broke. As with many aphids is parthenogenetic. That means it doesn’t require sex to reproduce. The form that grows roots settles on roots that are suitable and then punctures them using its mouthparts. It injects saliva into the roots, which triggers the root cells to expand into a form known as galls, which increase the amount of nutrients available and also provides protection. Then , it lay eggs which hatch and the winged forms of the aphids move along the roots, ascends the tree and is carried up into the air. If they locate an appropriate feeding spot, they’ll continue to multiply and the population can grow rapidly. In certain areas, 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 extends beneath the leaf and extends towards the leaf’s upper surface to let crawlers escape.

A variety of options were explored. Chemical defenses were tested and mostly 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) floods of vineyards during the dormant phase proved to be effective; vineyards that were planted in soils that were sandy did not suffer. However, for many vineyards not in sandy soils and couldn’t be flooded there was no hope.

A controversial solution was suggested. American vines that harbored the invader in the first instance was naturally protected from the phylloxera. In the areas where they were planted, they prospered, whereas the surrounding area was a scene of destruction. The wine they made tasted pretty bad, however, it was a better wine than none even if it was not, said the side that supported this method which was later referred to as the americanists. The tastings of the wines produced by the American vinifera varieties were arranged however the sad conclusion was that the wine, with its distinctive 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? Do they bring the strength of the vinifera with the resistance of the vinifera? The question was explored in an explosion of breeding efforts that resulted in what is today referred to as French-American hybrids. 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 interesting time in the breeding of vines.

In the following year, someone came up with an idea that was brilliant. It was in 1869 that monsieur Gaston Bazille suggested grafting vinifera varieties onto American rootstock. In the past, this appears to be an ideal solution, however at the time, there were many unanswered questions. The most important of these was the following. First, how long will the graft be in place? In addition, could the rootstock add the American wine’s character vinifera wine by altering quality of the vinifera grapes by this unnatural union between stock and scion? Thirdly what is the degree of resistance different rootstocks be? We already knew that certain American varieties were stronger against phylloxera than other varieties.

A first time that we have documented instances of this technique was in 1874 in the year 1874, when Henri Bouschet displayed an Aramon (Vitis vinifera) vine that was grafted onto an American rootstocks at the Congres Viticole at Montpellier. Within a few months, it was apparent that, contrary to what was expected the wine produced by vinifera vines that were grafted onto American rootstocks had all the characteristics of the vinifera grape while benefitting from the phylloxera resistance that is characteristic of American roots. It was the perfect circle. The plague came from America and was averted, but so too had the hope for salvation.

The idea was widely spread. The method of grafting was so simple to master that almost anybody could try it. The availability of American vines became more of a challenge as many wineries have begun to ban their importation in order to stop the remaining vineyards that were phylloxera-free from being afflicted by the disease. But not all were convinced by the revolutionary concept of the grafting. Some were against replanting, and the consequent loss of three years of production. They clung with fervor to their chemical treatments. However, common sense prevailed , and the grafters took the day. The lengthy work of replanting phylloxera-devastated vineyards began. It was not an easy procedure, and some of the more prestigious estates that were reluctant to remove their vines , kept them in place by applying insecticides as lengthy as it was possible. The selection of the right material for grafting was further complicated due to its length. It took time to locate American vine varieties that were well-adapted to chalky soils that prevailed in a few of France’s major regions.

The effects of the phylloxera outbreak continue to be felt. The primary impact was the alteration of the landscape of viticulture. If we take France to be an illustration, vineyards was reduced by a significant amount. Replanting also meant the existence of a form of viticultural bottle neck with traditional varieties being wiped out and being discarded to be replaced by more appealing commercially-oriented varieties. There are many regions where there are efforts to reintroduce the ‘lost’ varieties which lost their appeal in the replanting process.The replanting process is a long and tedious one. One of the oldest methods to plant vineyards is called marcottage or layering. It involves putting a still-attached vine in the ground , 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 a viable alternative. The reason is that the roots are vinifera and are therefore susceptible to the phylloxera. Prior to the crisis there were many vineyards that were planted en foule , basically randomly, without rows because of the continuous planting of canes and even the trunks renewing the vineyards without planting. Following the crisis, most wineries were planted with rows.

Additionally, the selection of rootstock, and its influence on parameters of grafts, like vigor, also became a factor, as well as a brand addition to the toolbox of viticulture.

Certain areas have been spared from the phylloxera virus, and are still plants that have been planted with their own root. The most well-known of these is Chile as well as South Australia, which have maintained a clean slate. Argentina as well as Washington State also have largely non-grafted vineyards. And while phytolloxera is present in both states, it doesn’t seem to be a huge issue. This could be due to the soil’s structure and in the case of Argentina, some have suggested that it’s because the majority of irrigation is done through regular flooding. Within Germany’s Mosel wine region, there remain many vines that are not grafted (again the soil appears to protect) in addition, the Douro is home to a well-known vineyard that is planted on its root: Quinta Do Noval’s Nacional. in the New Zealand’s Central Otago wine region the oldest vineyards in the region which date from the 1980s are not grafted (some have succumbed, unfortunately) as well as some of the older Oregon 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 has been a cease-fire. By grafting onto American rootstocks we can have wine, which is still in a way, the way it was. Roots and 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 type of phylloxera emerges which kills the vine? The idea is impossible.