Risk factors

The development of PVY infection results from the combination of sources of infection, either internal (volunteers or groundkeepers, seed tubers, weeds) and/or external (nearby potato crops, gardens, weeds such as Solanum dulcamara or Datura spp.), the significance of flights of aphids during the growing season (related to climatic conditions and nearby crops), the level of control measures taken in seed potato production (roguing, crop management such as weed control, crop protection, haulm destruction or field and lot inspection) and the susceptibility of the potato cultivar.

Expression of PTNRD after harvesting is also enhanced by an early infection and by warm temperatures during the growing season and during storage.