An international team of scientists has succeeded in mapping the phylloxera genome, more than 150 years since the tiny insect clandestinely travelled from the US to Europe and set about destroying huge swathes of vineyard.
It has taken more than 70 experts from eight countries nearly a decade to crack phylloxera’s genetic code, which includes ‘the largest gene family identified in a genome to date’, according to French research agency INRAE.
Why is phylloxera so feared?
After arriving in Europe as a stowaway in the early 1860s – and perhaps slightly earlier – the phylloxera pest is thought to have destroyed half of France’s vineyard area over the next few decades.
This naturally prompted despair among winemakers, and other countries were also badly affected, both in Europe and beyond.
Winemakers began to gain the upper hand once it was discovered that phylloxera could be beaten by grafting ‘vitis vinifera’ grapevines onto resistant American rootstocks.
This is still common practice, but not everywhere in the wine world. In many cases, ungrafted vines remain vulnerable to the pest, which attacks the roots in order to feed. Phylloxera therefore remains an ongoing concern.
Chile is considered the only major wine producing country to have largely avoided infestation, although pockets of untouched areas exist elsewhere, and the insect is believed to struggle on sandy soils.
The work to map the phylloxera genome, published in the BMC Biology journal, also shows that it likely comes from the upper Mississippi River.
The pest entered Europe by hitching a ride on the vitis riparia species, a wild type of American vine, according to the new research.
It is now hoped that unlocking phylloxera’s genome can help to improve ways of combating the insect.
INRAE said, ‘This new knowledge also serves to improve our understanding of biological invasions and their potentially disastrous consequences on agriculture and therefore on society and the economy.’
This page was originally published in 2010, but has been updated in July 2020.