Use of almond as interstock for PPV (sharka) protection in peach

Although no natural sources of resistance have been identified in peach, diverse experiments have demonstrated the possibility of inducing resistance to Plum pox virus through almond grafting.
As a result of the “Garrigues effect”, as we have called it, disease symptoms and virus accumulation progressively decrease in seedlings heavily infected with PPV-D after ‘Garrigues’ almond grafting.
Furthermore, grafting ‘Garrigues’ onto ‘GF305′ before PPV inoculation has completely prevented virus infection.
Based on these previous findings, we have used ‘Garrigues’ as an interstock (intermediate rootstock, bridge rootstock, intermediate wood, inter-stem, etc.) as an alternative way to protect peach cultivars against PPV. This is the first time that an almond cultivar has been used as an interstock to prevent sharka infection.
Thus far, we have only tested ten peach cultivars, which is a small representation of the huge catalog of Prunus persica available in the market.
Our tests have included cultivars with white and yellow flesh and cling and free stones, as well as nectarines and platycarpa peaches.
The following peach cultivars were grafted: ‘Maya’, ‘Transvalia’, ‘Romea’, ‘Catherine’, ‘Astoria’, ‘Tirrenia’, ‘Maruja M13′, ‘Levante 30′, ‘Alisio 15′ and ‘Carioca’. All were grafted onto ‘Garrigues’ wood that was already growing on ‘GF677′ and ‘Garnem’ rootstocks.
When the plants were ready (rootstock+interstock+peach cultivar), we tried to inoculate the growing peaches with sharka at least three times, with no success so far.
If the results are confirmed, we can say that we have a kind of “vaccine” for PPV on peach ready to be exploited at the commercial level.

X International Peach Symposium

M. Rubio, P.J. Martínez-García, F. Dicenta, P. Martínez-Gómez

Prunus, resistance, grafting, inter-stem, intermediate-rootstock

https://doi.org/10.17660/ActaHortic.2022.1352.17