Articles
EVALUATION OF RESISTANCE TO PLUM POX VIRUS IN APRICOT TREES
Plants remained ungrafted or were grafted onto PPV susceptible rootstocks of peach (GF305 or Rubira) and inoculated with PPV using either the chip-budding or aphid transmission methods.
Two strains of PPV were used for the inoculations: the D strain originating from infected apricots in the south-eastern part of France, and the Marcus (M) strain isolated from peach in Greece.
Inoculations were also developed on young plantlets transferred to the greenhouse following in vitro culture.
Symptoms of PPV infection developed more rapidly following inoculation by aphid transmission than by chip-budding, and the response of the plants to the M strain was generally greater than for the D strain.
Some apricot varieties showed a very high level of PPV resistance, occuring mainly in varieties originating from North America, i.e., Veecot, Stella, Stark Earli Orange et Henderson.
A significant level of resistance was transmitted from Stark Earli Orange to the progeny since 29% of the hybrids [Screara x Stark Earli Orange] appeared resistant.
Preliminary results concerning the evaluation of PPV resistance following in vitro culture, and the different approaches adopted to introduce this resistance into apricot varieties in France, are presented.