The cotton leafhopper burns more vineyards in France

his year, the cotton leafhopper Jacobiasca lybica has spread to new parts of France. In the Pyrénées-Orientales area in the south of the country, “it has spread like wildfire in the plains of Perpignan. And from Port-Vendres, it has spread to Rivesaltes”, explains Lionel Delbac, a researcher with Inrae in Bordeaux (UMR Save).

Unlike last year, though, the onset started later, around the end of August. “A rainy start to the summer and lower temperatures delayed the emergence of the insect until the end of July, then pressure soared at the end of August. Near Perpignan, vineyards have been devastated with differences depending on grape varieties: damage is limited for Carignan and Grenache but explosive on Syrah”, adds Delbac. Similarly, the insect has appeared in Aude, farther east. “It has been reported in the Narbonne and La Clape area where a spot has started”. In Var, the insect was initially spotted in Bormes-les-Mimosas and La Londe-des-Maures, but has now also travelled east along the coast towards Brégançon.

Delbac also recently discovered the Erasmoneura vulnerata leafhopper on a Cabernet-Sauvignon vine in a private garden right in the town centre of Bègles, near Bordeaux. The leafhopper is an invasive species originating in the Great Lakes region of North America and has been reported in northern Italy, Slovenia, Romania, Hungary and Switzerland. “Whereas the cotton leafhopper pricks the veins of the leaves, Erasmoneura pricks the limb and empties the cells, reducing the photosynthetic capacity of the primary and secondary shoots. However, because it pricks the limb, it does not carry viruses or phytoplasma”, explains the researcher.