Transformation of grapevine rootstocks with the coat protein gene of grapevine fanleaf nepovirus.

Control of fanleaf disease induced by the Grapevine Fanleaf Nepovirus (GFLV) today is based on sanitary selection and soil disinfection with nematicides. This way of control is not always efficient and nematicides can be dangerous pollutants. Coat protein (CP) mediated protection could be an attractive alternative. We have transferred a chimeric CP gene of GFLV-F13 via Agrobacterium tumefaciens LBA4404 into two rootstock varieties: Vitis rupestris and 110 Richter (V. rupestris X V. Berlandieri). Transformation was performed on embryogenic callus obtained from anthers and on hypocotyl fragments from mature embryos. Success of the transformation was assessed by polymerase chain reaction and Southern analyses. Transformants with a number of copies of the CP gene varying from one to five were obtained. Enzyme-linked immunosorbent assay with virus-specific antibodies revealed various levels of expression of the coat protein in the different transformants.