Transgenic rootstocks expressing GFLV coat protein gene in a three years field trial ; resistance assessment, impact on GFLV diversity and exchanges between rootstock and scion
Résumé
Transgenic rootstock lines expressing the full-length translatable coat protein (CP) gene of Grapevine fanleaf virus strain F13 (GFLV-F13) are under evaluation in an open-field trial. Control plants were contaminated after nematode-mediated transmission of GFLV after three years. In contrast, viral infection of non-transgenic scion (Vitis vinifera cv. Pinot Meunier) was delayed in vines grafted onto transgenic rootstocks. Sequencing of CP genes from GFLV isolates from this field, suggests that CP gene-expressing transgenic rootstocks do not influence significantly natural viral biodiversity. Transgenic-derived expression products were detected in GM rootstocks. However, their systemic movement was not detected suggesting that the scions remain truly wild-type. All experiments were coconstructed and followed within a Local Steering Committee. Thus, this field trial is a unique support for the assessment of environmental impact of genetically-modified plants (GMPs) and a survey of public perception of GMPs.