SUSCEPTIBILITY AND TOLERANCE TO VIRUSES OF THE PRUNUS DOMESTICA SPECIES
- Susceptibility is the higher or lower degree of response of a plant to a virus infection;
- Tolerance is the absence of macroscopic symptoms in an infected plant.
The plant is apparently healthy, but the infection agent may exist in it in an appreciable amount.
The Prunus domestica species is characterized by a high genetic heterogeneity that is expressed in the varieties by a great variability of morphologic, physiologic and biologic characters. Susceptibility of the Prunus domestica species to viruses seems extremely fluctuating according to varieties, although our knowledge on the subject is but fragmentary.
When comparing the Prunus domestica species susceptibility to that of other Prunus species (P. persica, P. avium) with regard to virus diseases common to these species (Line Pattern, Ring Spot, Prune Dwarf), it may be generally observed that the Prunus domestica species has a certain tolerance.
The Prunus domestica species therefore seems to exhibit a rather moderate susceptibility to viruses, but there are three types of virus diseases that often cause high losses in some very susceptible varieties: their number is fortunately reduced. Production decrease or lowering of fruit marketing value appears only in these susceptible varieties