|Mohamad Chikh-Ali||University of Idaho|
|Lisa Tran||University of Idaho|
|Alexander Karasev||University of Idaho|
Potato virus Y is the main cause of potato seed lot rejections and downgrades, and its management in seed potato proved difficult in many regions of the world. Here, the potential of the age-related resistance (ARR) as a management tool for PVY was investigated in transplants of a potato cultivar Yukon Gold, to the infection with PVYNTN strain, in greenhouse experiments. Within the first three weeks after transplanting into soil (W1-3), Yukon Gold plants developed ARR that impaired the systemic movement of PVYNTN into upper, non-inoculated leaves and concomitant translocation into progeny tubers starting from week four (W4) after transplanting. The yield and quality of tubers from PVY-infected plants with the established ARR (W5-W8) were comparable to the healthy controls, suggesting late PVY infection would not significantly affect commercial potato production. Potato plants inoculated early (W1-W2), prior to the establishment of the ARR, exhibited a 100% primary systemic infection with PVYNTN and produced fewer tubers of smaller sizes, exhibiting PTNRD, which resulted in up to 70% yield reduction compared to plants inoculated later in the season, W5-W8. This ARR effectively restricted the systemic movement of PVY in potato foliage and limited virus translocation into progeny tubers of all plants inoculated later in the season, W5-W8. This study suggests that PVY management programs should focus more on the early stages of the potato development, prior to the onset of the ARR to PVY.