Erythroneura spp. (Cicadellidae) feeding behaviour on grapevine

Leafhoppers of the genus Erythroneura cause severe damage in vineyards of North America. Between 2006 and 2008, a survey conducted in British Columbia, Ontario and Quebec vineyards showed that Erythroneura species represented the most important group of leafhoppers. Some of them were detected positive for Aster Yellow phytoplasmas. In order to understand the mechanisms of phytoplasma acquisition and transmission, the feeding behaviour of E. elegantula, E. vitis and E. ziczac was investigated by way of electropenetrography and histology. Results have shown that the three Erythroneura species essentially feed in the mesophyll (for ca. 80% of the time), and also in the xylem (ca. 20%). No puncture was recorded in phloem sieve elements. Our results raise the question of phytoplasma acquisition by Erythroneura in mesophyll, a compartment known to occasionally contain phytoplasmas.