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Abstract

The ectoparasitic dagger nematode Xiphinema index specifically transmits Grapevine fanleaf virus (GFLV) which is responsible for a progressive degeneration of grapevines occurring in most vineyards worldwide. In the last years, new data on the biology and ecology of the vector nematode and on the virus-nematode and plant-nematode interactions have contributed to draw new alternatives to chemicals for nematode control. New insights have been acquired into its genetic diversity at both the world (phylogeography) and local (field) scales. Moreover the long nematode survival and its long virus retention together with the location of the nematode in deep soil layers highlight the interest of nematode-resistant rootstocks as priority control alternative. Some Muscadine accessions are currently the most efficient resistance sources. Despite the crossing difficulties between the genera Vitis and Muscadinia, F1 and BC1 resistant material has been selected and the first X. index resistant rootstock has been recently released. Results obtained with this rootstock, despite its agronomical defaults, are a proof of concept of the resistance strategy. Recent work aims to unravel genetics of this muscadine-derived resistance in order to optimize its durability in future rootstocks. Perspectives of integrated control rely notably on combination of fallow crops reducing nematode numbers between two successive grapevine plantings and nematode-resistant rootstocks.