Potato virus A

(PVA)

• Causal agent and transmission

PVA is a Potyvirus transmitted by many aphid species in the non-persistent manner, notably Myzus persicae, Macrosiphum euphorbiae, Aphis frangulae and A. nasturtii.  

As in the case of PVY, PVA can be acquired by M. persicae in less than one minute and transmitted to another leaf equally rapidly with no latent period. The virus may be retained for 20 min to 2 hours after its acquisition before it loses its infectivity.

The host range of PVA is narrow and confined to Solanaceae such as tobacco or tomato.

• Significance 

Virus A is widespread in most potato-growing countries but it is considered much less important than PVY. Most cultivars are resistant and yield losses are usually low even if the level of infection can reach up to 40% in some cultivars or in the case of co-infection with other viruses.