Wild and ornamental species of this genus may also become infected by some strains of the virus. Economic Importance of Plum Pox Plum pox is economically important because it can cause fruit to be unmarketable and can decrease the yield of infected trees. In southeastern France, a newly identified strain of PPV induces severe necrosis, resulting in early leaf drop and tree decline, even in the absence of endemic Prunus viruses. Spread of Plum Pox Several aphid species can transmit plum pox within an orchard and from other trees to nearby orchards. Long-distance spread usually occurs as a result of the movement of infected nursery stock or propagative materials.
Aphids spread plum pox by carrying the virus in a nonpersistent manner.
This means that the virus remains on the stylet from minutes to perhaps a few hours. These species include Myzus persicae, Aphis spiraecola, A. gossypii, and A. fabae. Some PPV strains have been identified that are not transmissible by aphids. Sources of resistance exist in Prunus but are not abundant. This provides a unique source of germplasm for future breeding programs worldwide.