Fig. 1

Map of the vineyard plots. Seven pairs of plots that differed in their downy mildew incidence and severity were selected for the present study. They were all located in France (map 1) in the Nouvelle-Aquitaine region (map 2). They belonged to four wine-growing areas, namely, Médoc (ME), Libournais (LIB), Entre-deux-Mers (E2M) and Côtes de Buzet (CDB) (maps 3a–d). Plots belonging to the same pair are represented with the same color, with symbols indicating high and low downy mildew incidence and severity (triangles and circles, respectively). The distance between plots within a pair ranged from 0 km for pair CDB2 (adjacent plots) to 7.5 km for pair E2M (Table 1)