OCCURRENCE OF PHYTOPLASMA INFECTION IN EUROPEAN PLUMS (PRUNUS-DOMESTICA)

Phytoplasmas were constantly detected by the DAPI technique and by PCR amplification of DNA From European plums (Prunus domestica) cv 'Susin a di Dro' with symptoms similar to those reported for Japanese plum le ptonecrosis. These symptoms included upward rolling of the leaves, whi ch also became bronzed-reddish, thick and brittle, growth of normally dormant axillary buds, off-season growth during November-January and p hloem necrosis. Trees with symptoms showed progressive decline. RFLP a nalysis revealed that the phytoplasma isolated from the affected plum trees is closely related to the other phytoplasmas present in Prunus s pecies in Europe and can be included in the apple proliferation cluste r. Although Japanese plum leptonecrosis is common in Europe, this is t he first report of a wide-spread phytoplasma-induced decline in a cult ivar of European plum.