Cloning and sequence analysis of 16S ribosomal DNA of phytoplasma associated with witches' broom of bamboo

With specific primers designed based on phytoplasmal 16S ribosomal RNA gene sequences, a 1.2kb DNA fragment was amplified by direct PCR and nested PCR from total DNA of bamboo showing witches broom symptom. The amplified fragment was ligated into pGEM-T easy vector and then transformed into DH5 strain of E. coli. The clones were verified by restriction enzyme digestion and PCR. Sequence and homology analyses showed that this phytoplasma strain shares high homology (99.0%) with the phytoplasma of Aster Yellows that belongs to 16SrI group. A phylogenetic tree of bamboo witches broom phytoplasma strain was established based on 16SrDNA sequences. The taxonomic status of bamboo witches broom phytoplasma collected in Yunnan province is consistent with that reported before.