First Report of an Aster Yellows Phytoplasma as the Cause of Rose Balsam Phyllody in China

In July 2010, symptoms suggestive of phytoplasma infection were observed on Rose Balsam ( Impatiens balsamina ) around Yangling, China. Nested polymerase chain reaction with universal 16S rDNA phytoplasma primers P1/P6 and R16F2n/R16R2 yielded amplicons of expected size (1.2 kb) from all symptomatic, but not asymptomatic, leaf samples. Sequencing results and NCBI BLASTn analysis of the 1246 bp products (R16F2n/R16R2) showed that the phytoplasma belonged to group 16SrI. Restriction fragment length polymorphism and phylogenetic analysis showed the phytoplasma had a close relationship to subgroup 16SrI‐D. This is the first report of a phytoplasma infecting Rose Balsam.