Practical observations on the presence of AP disease (‘Candidatus Phytoplasma mali’) in Trentino (Italy)

Abstract: An epidemic spread of apple proliferation, a disease caused by ‘CandidatusPhytoplasma mali’, started in Trentino (north-eastern Italy) in 1998. This disease was alreadyknown in this region, as its first report dates back to 1951, but this was the first time that itshowed an epidemic behaviour, spreading over both mountain and bottom-valley environments.Since 2008 the distribution of this disease appears to be locally, again due to a typical “recovery”phenomenon. In this note some field observations carried out in two research projects, funded byProvincia di Trento (SMAP1 and SMAP2), are reported. Symptoms, transmission trials by insectvectors and root bridges, monitoring surveys, practical control experiences and examples for“recovery” are presented.