‘Candidatus Phytoplasma pini’ affecting Taxodium distichum var. imbricarium in China

Suspected phytoplasma symptoms were observed in Taxodium distichum var. imbricarium at the Nanyang Normal University campus, Nanyang City, Henan, China. The major symptoms consisted of little necrotic leaves, abnormal proliferation of twigs and overall necrotic appearance of the whole tree. Nested PCR was performed to confirm the association of phytoplasmas with symptomatic T. distichum var. imbricarium. PCR amplification using universal phytoplasma primers P1/P7 followed by R16F2n/R2, amplifying 16S ribosomal gene, yielded positive results. Amplified products were cloned and sequenced. Blast analysis showed 99% sequence identity with several ‘Candidatus phytoplasma pini’. Phylogenetic analysis confirmed the close relationship of the phytoplasma from T. distichum var. imbricarium with ‘Ca. P. pini’ belonging to 16SrXXI group. Hence this is the first report of association of ‘Ca. P. pini’ with a disease of T. distichum var. imbricarium tree in China.