INTERSPECIFIC TRANSFER OF RESISTANCE TO PLUM POX VIRUS IN PRUNUS BY GRAFTING

M. Rubio, P. Martínez-Gómez, J.A. García, F. Dicenta
Plum pox virus (PPV, sharka disease) is a serious limiting factor for Prunus production (mainly apricots, plums, prunes and peaches) in those areas affected. Previous works showed that almond ‘Garrigues’ (but not other – nine almond cultivars) eliminated sharka symptoms and PPV in heavily infected ‘GF305’ seedlings. In this study, grafting almond cultivar ‘Garrigues’ onto ‘GF305’ peach seedlings heavily infected by a Dideron strain of Plum pox virus (PPV) progressively eliminated sharka symptoms and drastically reduced virus accumulation in ‘GF305’ rootstock. This response appears to be specific between the almond and peach, since it was not consistently observed by grafting ‘Garrigues’ onto other Prunus species such as plum (‘Adesoto’) or apricot (‘Real Fino’). Furthermore, grafting ‘Garrigues’ onto ‘GF305’ before PPV inoculation completely prevented virus infection showing that the resistance is constitutive and not induced by the virus. In addition, in the previously diseased ‘GF305’, after removing the grafted ‘Garrigues’, sharka symptoms reappear. This fact suggests that resistance may be due to the transfer of a defense factor from ‘Garrigues’ almond through the graft union and its interaction with specific factors of ‘GF305’ peach to produce the antiviral response. These results open new avenues to a potential protection against PPV in peach, the most economically important affected species and one of the species where no natural resistance sources have been identified yet.
Rubio, M., Martínez-Gómez, P., García, J.A. and Dicenta, F. (2015). INTERSPECIFIC TRANSFER OF RESISTANCE TO PLUM POX VIRUS IN PRUNUS BY GRAFTING. Acta Hortic. 1063, 117-122
DOI: 10.17660/ActaHortic.2015.1063.16
https://doi.org/10.17660/ActaHortic.2015.1063.16
peach, almond, grafting, Prunus, Plum pox virus, PPV, sharka, potyvirus, resistance
English

Acta Horticulturae