THE USE OF GREEN FLUORESCENT PROTEIN-TAGGED RECOMBINANT PLUM POX VIRUS (PPV) TO STUDY VIRAL INVASION IN PPV/PRUNUS INTERACTION

Abstract

The sharka disease caused by the potyvirus PPV (Plum pox virus) is one of the most serious viral disease affecting stone fruit trees. PPV/Prunus interaction is now quite well known at the whole plant level. However, few data are available on the interaction between the virus and Prunus at the cellular level. A green fluorescent protein (GFP)-tagged PPV, constructed by JA Garcia team, is now available to facilitate studies at the cellular level. In this study, we are first focusing on testing PPV-GFP as a new tool to follow PPV in 'GF305' susceptible host. Healthy and PPV-GFP infected 'GF305' are cultured in vitro. In vitro PPV-GFP infected 'GF305'/'GF305' or 'GF305'/PPV-GFP infected 'GF305' homografts were used to study the ability of the virus to spread from one plant to another. PPV-GFP can be detected in the whole plant by using a fluorescence binocular microscope showing the systemic spread of the recombinant virus. In both ways of grafting, PPV-GFP can be detected in the graft or in the rootstock one or two month after the graft. The presence of the virus was confirmed by ELISA. GFP tagged PPV offers a new and powerful tool that will be used to compare the dynamic of infection between resistant, tolerant and susceptible Prunus, especially in PPV/apricot interactions.