Investigation on the apple proliferation epidemics in the orchards of the Pelion Mountain and preliminary observations on possible phytoplasma vectors

Abstract

The apple producing region in the Pelion Mountain (Magnesia prefecture, Thessaly, Greece) is suffering for more than 10 years from the apple proliferation disease. The orchards are basically planted with cv 'Starking Delicious', are grafted on seedling rootstocks and are older than 40 years. The presence of the 'Candidams Phytoplasma mali' was proven by PCR/RFLP analyses as well as by sequencing. 'Ca. P. pyri' was also detected in at least three different orchards. First attempts to identify the vectors were carried out by monitoring the insect populations in 8 different orchards, one species of psyllids morphologically identified as Cacopsylla pulchella (Low) was the most present insect in the orchards all along the two-month monitoring (May/June). Cacopsylla mali (Schmidberger) was also present in the orchards but in lower numbers. The monitoring is continued and still in progress.