Archivio Journal of Plant Pathology

Abstract:

The incidence of Potato virus Y (PVY) and Potato leafroll virus (PLRV) was studied in field crops and potato seeds in Greece. In 2006, 1-17% of the plants in ware potato crops were affected, the autumn more than the spring crops. PVY infections were detected in ware potato and non-certified seeds in all areas at rates of up to 100% of the suspected plants or tubers. PLRV was widespread mainly in the upland crops in Xanthi (37.8%) and Kilkis (30%), and in non-certified seeds in Pella (29%). A limited number of field plants were infected also by Tomato spotted wilt virus (TSWV). More than 50% of the potato seed lots produced in Thessaloniki and Arkadia were rejected in 2005 and 2006 during their final stage of certification due to heavy PVY infection (up to 60%). Both PVY and PLRV were also detected with a different incidence in several imported lots of the categories “basic” and “certified” in 2005 and 2006. In “basic” seeds, out of 96 and 84 lots tested, PVY was detected in tubers of 25 and 33 lots, and PLRV in 12 and 3 lots in the respective years. Occasionally, Potato virus X (PVX) was detected in 9 and 7 “basic” seed lots of 2005 and 2006. In “certified” seed-potatoes, PVY was detected in 86 and 145 lots out of 302 and 336, while PLRV was found in 31 and 55 lots in 2005 and 2006, respectively. The results showed that PVY is widespread in Greece and that PLRV is restricted to cold mountainous regions. It was also shown that non-certified seeds are highly infected with PVY, while certified seeds were only occasionaly infected at high rates.