Inheritance of the stark early orange apricot cultivar resistance to Plum pox virus

Due to the economic impact of PPV disease on Mediterranean apricot production, there is great interest in finding solutions to overcome the problem. From the genetic point of view, a source of resistance has been identified in Stark Early Orange, an American cultivar. In order to assess the inheritance of the resistance, three contrasted progenies were characterised by graft-inoculation with the PPV-D strain: selfing of the resistant Stark Early Orange cultivar, hybrids between the resistant Stark Early Orange and the susceptible Bergeron cultivar, and selfing of the susceptible Bergeron cultivar. The absence of leaf symptoms were validated by DAS-ELISA, and the observations were continued over 4 consecutive growth periods. Preliminary results suggest that the resistance of Stark Early Orange cultivar to PPV is dominant and controlled by at least 3 genes. A validation phase in under progress with other progenies.