Situation of plum pox potyvirus in Valencia, Spain
Plum pox potyvirus (PPV- EPPO A2 quarantine pest) was first detected in Spain in 1984 on Japanese plum (Prunus salicina cv. Red Beaut) grown in Sevilla, Murcia and Valencia and on peach (cv. Rojo del Rito) grown in Lerida. So far, only PPV-D isolates have been found in Spain. In the Valencia region, a significant spread of PPV has been observed since 1988, with severe losses, particularly in early apricot cultivars. Between 1991 and 1996 more than 600,000 infected trees (apricots and Japanese plums) were removed in Valencia, but spread of the disease was not restrained. However, it is noted that peach trees are scarcely affected by PPV. This situation in Valencia might be explained by different factors: 1) PPV was first introduced on Japanese plum, which was a new natural host at that time, and this probably allowed the disease to spread for several years without being noticed; 2) PPV is not causing significant symptoms and losses in Japanese plum fruits, which rendered early eradication more difficult; 3) in Valencia region, there is a predominance of small plots where Japanese plum, apricot and peach are grown together, within a large area of extensive citrus cultivation, which implies a great abundance of aphid vector populations.
Sources
Llácer, G.; Cambra, M. (1997) Thirteen years of sharka disease in Valencia, Spain.
Abstract of a paper presented at the ISHS XVII International Symposium on virus diseases of fruit trees, Bethesda, US, 1997-06-23/27, p 32.