Cucumber mosaic virus infection does not increase the translocation of the green fluorescent protein from GM rootstock to non-GM scion in transgrafted plants.

Plant viruses use the plasmodesmata and vascular systems to spread systemically in a plant, which may influence the translocation of exogenous transgene products in genetically modified (GM) plants. Transgrafting is a technique that involves the use of GM plants as grafting partners for non-GM plants, and yields non-GM edible harvests from transgrafted crops; thus, there is potential for its distribution as a non-GM product. However, when growing in agricultural fields, transgrafts are exposed to biotic stresses, such as plant virus infections. In this study, we investigated the influence of a plant virus infection on translocation of transgene products between GM and non-GM parts of transgrafts. We generated homo- and hetero-transgrafts of green fluorescent protein (GFP)-expressing GM tomatoes and GM Nicotiana benthamiana rootstocks with non-GM tomato scions and infected them with cucumber mosaic virus (CMV), a major plant virus, and analyzed the translocation of GFP protein in transgrafts. The results showed that CMV infection did not promote GFP transfer from GM rootstock to non-GM scions.