‘Candidatus Phytoplasma pyri’ in peach orchards in Spain

Symptoms similar to those associated with phytoplasmas such as early reddening, curling of leaves, chlorosis, reduced vigour, abnormal fruits, irregular branches, and in some cases death of the trees, were observed in peach orchards in the area of Lleida (northeast of Spain) in 2013. The objective of this study was to carry out surveys on a larger surface area in Lleida to determine the possible spread of the disease, as well as to determine a possible transmission between peach trees through insect vectors. Results obtained after analysis for phytoplasma detection by nested PCR with generic phytoplasma rDNA primers P1/P7 and R16F2n/R16R2 and sequencing, indicated the presence of ‘Candidatus Phytoplasma pyri’ in the samples and not the one of the expected ‘Ca. P. prunorum’. Results were confirmed by the study of gene imp. The disease is similar to the peach yellow leaf roll disease identified in California. The pull up of a great number of pear tree orchards, with new plantations of peach trees may have led to the transmission of the phytoplasma through Cacopsylla pyri to peach.