IDENTIFICATION OF A PHYTOPLASMA ASSOCIATED WITH CHERRY VIRESCENCE IN CHINA
R. Gao, J. Wang, W. Zhao, X.-D. Li, S.-F. Zhu, Y.-J. Hao
During a field survey in 2007, sweet cherry (Prunus avium L.) trees with symptom of virescence were found in Yantai, Shandong province of China. Total DNA extracted from symptomatic and symptomless trees was subjected to nested PCR with universal primers for phytoplasmal 16S rRNA gene. A specific fragment of approximately 1.2 kb in length was amplified from diseased but not from healthy samples. Phylogenetic analysis of the 16S rRNA gene sequence showed that the phytoplasma isolate associated with cherry virescence in Yantai (ChV-YT), belongs to ‘Candidatus Phytoplasma asteris’ (16SrI group). Phylogenetic and computer simulated RFLP analysis of 16S rRNA gene revealed that ChV-YT represents a new subgroup in the aster yellows group, tentatively designated as 16SrI-S. This is the first report of a phytoplasma associated with cherry virescence in China.