Biology and ecology of the Flavescence doree vector Scaphoideus titanus: a review

Flavescence dor,e is a serious disease for European vine growers. Indeed, Flavescence dor,e causes yield losses and lower grape quality. As a consequence, Flavescence dor,e is costly and needs advanced control strategies. For instance, in 2005, 34 million Euro was given to Italian vine growers to compensate losses due to the disease. The infection by Flavescence dor,e results from the association of a phytoplasma and the leafhopper vector, Scaphoideus titanus. Despite mandatory controls using insecticides, Flavescence dor,e is still spreading in Europe. Here, we review the biology and ecology of S. titanus to suggest improved management techniques. The main findings are as follows. (1) The long-distance spread of S. titanus is mainly due to human activities, and all European vineyards are susceptible to be colonized. (2) S. titanus is an efficient vector because it can reach a high population level and it is specific to Vitis spp. (3) Current control and prophylaxis are insufficiently effective. (4) Variation in vector populations and vector capacities lead to differential risks of plant infection. Factors driving such population variations could be modeled to improve S. titanus control. (5) Feeding behavior is a key factor in the phytoplasma-vector relationship. (6) The infection risk is mainly limited by vector control. To decrease pesticide use, a cross survey of the vector population and of the infected stocks triggers mandatory treatments. (7) Alternative sustainable methods or strategies are required to reduce insecticide use and increase control efficiency. In the short term, new models could support the establishment of more sustainable pest management operations. In the long term, innovative techniques involving symbionts, mating disruption and a push-pull strategy could improve S. titanus and Flavescence dor,e control with less environmental impact.