Detalle de: Plum pox virus (sharka) resistance in peach by grafting ‘Garrigues’ almond as interstock

• Sources of resistance to sharka ( Plum pox virus ) have not been identified among peach varieties. • Grafting of ‘Garrigues’ almond induced plum pox virus resistance in peach. • ‘Garrigues’ graft as interstock could serve as a kind of "vaccine" against PPV-Dideron in peach that is ready to be used commercially. Sources of resistance to sharka ( Plum pox virus , PPV) have not been identified among peach [ Prunus persica (L) Batsch] cultivars to date. However, several studies have shown the possibility of inducing resistance to PPV by grafting with the ‘Garrigues’ almond [ P. dulcis (Mill) D. A. Webb] cultivar. The so-called “Garrigues effect” progressively reduces the symptoms of the disease and the accumulation of the virus in ‘GF305’ peach plants highly infected with PPV Dideron after grafting ‘Garrigues’. In addition, grafting 'Garrigues' onto ‘GF305’ before inoculation completely prevents infection by the virus. In this work, the ‘Garrigues’ cultivar has been used as an interstock to prevent PPV infection in peach. We have evaluated a collection of peach cultivars representing red and yellow skin, white and yellow flesh, and free and cling stones, in addition to platycarpa peaches (‘Maya’, ‘Transvalia’, ‘Romea’, ‘Catherine’, ‘Astoria’, ‘Tirrenia’, ‘Maruja M13’, ‘Levante 30′, ‘Alisio 15′ and ‘Carioca’). The cultivars were grafted onto ‘Garrigues’ that was already growing on ‘GF305’, ‘GF677’ and ‘Garnem’ rootstocks. Once the assayed plants were ready and fully developed [rootstock + interstock (‘Garrigues’) + peach cultivars], we graft inoculated the rootstocks and the growing peach plants with PPV at least three times. We were not able to obtain symptoms or detect the virus by RT-PCR in any of the cases, despite the proven susceptibility of these cultivars. In view of the results, we can affirm that using the ‘Garrigues’ graft as interstock could act as a kind of "vaccine" against PPV-Dideron in peach that is ready to be used commercially.