Detection and Identification of Group 16SrVI Phytoplasma in Willows in China

In 2010 and 2011, willow proliferation disease was observed in Erdos, Inner Mongolia, China. The phytoplasma-specific 16S rRNA gene fragment of 1.2 kb was amplified by a nested PCR with universal primer pair P1/P7 followed by R16F2n/R2. Phylogenetic and virtual RFLP analyses revealed that the phytoplasma associated with willow proliferation was a member of subgroup 16SrVI-A. The field survey indicated that the incidence of willow proliferation in Erdos was approximately 36.84%. To our knowledge, this is the first record of group 16SrVI phytoplasma infecting willow in China.