Information on PTNRD
PTNRD is short for Potato Tuber Necrotic Ringspot Disease which is a tuber defect associated with infection by the necrotic strains of PVY. Affected tubers show roughened rings of darker brown or reddened skin. Necrosis beneath the rings may extend into the tuber flesh. Our research is investigating which potato varieties are affected by this defect, and to what degree.
Tuber disease caused by PVY has swept across Europe in the past two decades. The reasons for this are unclear, but mild symptoms and slow recognition by seed certification programs did play a role. In the USA, the tuber necrotic strains of PVY are still confined and at low levels. A concerted effort by seed certification programs sanctioned by grower participation could keep this disease in check and prevent PVY from becoming a tuber quality disease – BUT the time to act is now. Delays will lead to widespread distribution of the disease, making management more difficult.
PVY strains in the USA There are different types of PVY called “strains” and individuals or “isolates” in a strain, vary in biological properties.
In the past decade, PVY has re-emerged in the USA as a serious disease. We are finding that strains PVYNWi and PVYNTN are more prevalent.
Some potential reasons -