First report of ‘Candidatus Phytoplasma pyri’ in Portugal
A study has recently been carried out in Portugal on the following phytoplasma diseases of fruit trees: apple proliferation, pear decline (both EPPO A2 List) and European stone fruit yellows (EU Annexes) which are associated with ‘Candidatus Phytoplasma mali’, ‘Ca. P. pyri’ and ‘Ca. P. prunorum’, respectively. Until this study, there was no evidence of any of these diseases in Portugal, or evidence of the presence of their psyllid vectors (except Cacopsylla pyri which is known to occur in Portuguese pear orchards). During this study, ‘Ca. P. mali’ and ‘Ca. P. prunorum’ were not found in plant samples collected from fruit tree orchards. However, the presence of ‘Ca. P. pyri’ was detected (nested-PCR, RFLP, nucleotide sequencing, real-time PCR) in some psyllid and pear tree samples. This is the first time that ‘Ca. P. pyri’ has been detected in Portugal. Further studies are being carried out on pear decline to evaluate its distribution and prevent its spread.
The situation of ‘Candidatus Phytoplasma pyri’ in Portugal can be described as follows: Present, detected for the first time in pear orchards in 2012.
Sources
Sousa E, Marques A, Mimoso C, Cardoso F (2012) First occurrence of pear decline disease in Portugal. Abstract of a paper presented at the 22nd International Conference on virus and other graft transmissible diseases of fruit crops (Roma, 2012-06-3/8), p 11.