Comparison of the viral transmission efficiency of different grafting techniques on grapevines

With the objective of screening a great number of grapevine varieties for their resistance to virus diseases, we looked for the most appropriate technique of inoculation. As the mechanical inoculation of a virus to the grapevine succeeds only under special conditions, we compared different grafting techniques: dormant grafting and green grafting, the last with and without previously rooted rootstock. For each of these three methods, the inoculum was used as the stock on one hand, as the scion on the other hand. This study proved that the dormant grafting technique using the inoculum as the rootstock is the most efficient technique. Nevertheless, good results were obtained by using the green grafting technique without previously rooting the rootstock, the inoculum being also used as the rootstock. As the green grafting method doesn't require a great area, is not time-consuming and can be performed throughout the year, it seems therefore to be a very convenient method of inoculating a great number of varieties.