Evaluation of resistance to sharka (Plum pox virus) of several Prunus rootstocks

Abstract

Sharka (Plum pox virus, PPV) severely affects the production of most Prunus species in the areas affected by the disease. In this study, the resistance of 15 Prunus rootstocks to a Dideron type isolate of PPV was evaluated under controlled conditions in an insect-proof greenhouse. After four cycles of study, ÔGF677Õ almond · peach hybrid, ÔMyrobolan 29CÕ plum and ÔL2Õ cherry did not show any symptoms and were ELISA-DASI and RT-PCR negative. These were considered resistant to PPV. The rest of the rootstocks assayed showed symptoms of sharka (confirmed by ELISA-DASI or RT-PCR), although the level of susceptibility was different for each rootstock. ÔGF305Õ peach, ÔPuebla de SotoÕ plum and ÔReal FinoÕ apricot, were highly susceptible to PPV, showing strong sharka symptoms and being ELISA and RT-PCR positive. ÔMarianna 2624Õ plum, ÔAC 9921-07Õ hybrid and ÔCP-2Õ plum showed susceptibility to PPV confirmed by ELISA-DASI and RT-PCR positives. ÔNemaguardÕ and ÔNemaredÕ hybrids, ÔTorinelÕ plum and ÔSTN2Õ hybrid showed an intermediate susceptibility to PPV with slight sharka symptoms and were ELISA-DASI and RT-PCR positive. Whereas, ÔMontclarÕ peach and ÔEvricaÕ hybrid showed moderate resistance to PPV with slight sharka symptoms and were ELISA positive but RT-PCR negative. The results open new possibilities in the search for different sources of resistance to PPV within Prunus.

PPV susceptibility of commonly used peach rootstock-scion combinations

“…According to our results, out of combinations containing this rootstock, only the 'Cadaman' x 'Michelini' showed a tolerant feature. Th e rootstock 'GF677' has been reported to be resistant to PPV-D strain according to Rubio et al (2005), but the interaction with the scion is not clear, since two PPV-D isolates were identifi ed from the 'GF677' x 'Babygold 6' combination. Th e PPV susceptibility of 'Babygold 6' cultivar was confi rmed by our results.…”

Evaluation of the Prunus interspecific progenies for resistance to Plum pox virus

“…A solution can be found in using PPV resistant wild species closely related to peach such as P. davidiana (Anonymous 1974) and P. amygdalus (Dicenta et al 2002;Rubio et al 2003a). Interspecific hybrids GF 677 and Cadaman (Prunus amygdalus × Prunus persica and P. davidiana × P. persica, respectively) were shown to bear resistance to PPV (Rubio et al 2005;Polák & Oukropec 2010). They represent a good resistance potential to PPV in peach.…”

Epidemiología de Plum pox virus y Citrus tristeza virus en bloques de plantas de vivero. Métodos de control

“…Los datos obtenidos en condiciones naturales de inoculación por pulgones muestran una alta susceptibilidad de los ciruelos Mariana GF8-1 y Adesoto 101. Estos resultados están de acuerdo con los obtenidos por Rubio et al, (2005) que citaron la alta susceptibilidad de ambos patrones mediante injerto de inoculación. Nemaguard resultó también un patrón muy susceptible, aunque menos que Mariana GF8-1 o Adesoto 101.…”

“…Aunque es conocido que Prunus cerasifera es susceptible a la infección por PPV (James y Thompson, 2006), diferentes clones de este patrón, como BN 4Kr y Mirobolan 29C, han sido descritos como resistentes a PPV-D (Minoiu, 1998;Rubio et al, 2005).…”

“…En este sentido diversos trabajos han evaluado la susceptibilidad de diferentes patrones de frutales de hueso a la infección por PPV, mayoritariamente mediante desafíos con inoculación por injerto (Minoiu et al, 1998;Pascal et al, 2002;Rubio et al, 2005;Boeglin et al, 2006). En estos estudios se describieron diferentes patrones como resistentes: BN 4Kr (Prunus cerasifera) (Minoiu et al, 1998), GF677, Mirobolan 29C y L2 (P. lannesiana) (Rubio et al, 2005).…”