Leo Laliman

Leo Laliman was a winegrower and viticulturist from Bordeaux, France. He, along with fellow winegrower Gaston Bazille, is largely accredited for the discovery that when European vines are grafted with suitable American rootstock, they become resistant to grape phylloxera. This discovery was very relevant at the time, when France was suffering from a severe wine blight induced by the same phylloxera.

While Laliman was praised for his discovery, he was also a controversial figure at the time; for undocumented reasons, he was also branded by many as the introducer of the phylloxera, and, by extension, the crippling blight that came with it.

The blight, termed the Great French Wine Blight, was a severe blight of the mid-19th century that resulted in the destruction of over 4 million vineyards and 40% of all the grape vines in France, and that subsequently laid waste to the wine industry there.

This blight was brought on by a species of aphid that originated in North America and was carried across the Atlantic Ocean sometime in the late 1850s/early 1860s. However, how the phyolloxera had survived the journey remained a point of much debate; Europeans had experimented with American vines for centuries without any pestilential problems. Eventually, it was decided that, following the invention of steamboats, the grape phylloxera were able to survive the shortened journey.

The first instance of the blight was recorded sometime in the early 1860s, and France suffered the blight for a 15-year period, without any solution. Eventually, Jules-Emile Planchon and two colleagues made an important discovery; the discovery that sourced the aphid phylloxera to the blight itself — up until then, the source of the damage was unknown. In 1870, American entomologist Charles Valentine Riley confirmed Planchon's theory. However, this discovery caused controversy; some met it with optimism, saying that now that the cause had been found, it would just be a matter of elimination. Others disagreed completely with the theory, saying that the grape phylloxera were merely a symptom, an effect, of the blight, rather than the source.

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