Phylogenetic analysis of phytoplasmas based on sequences derived from the secA and 23S rDNA genes
نویسندگان
چکیده
Phylogenetic analysis of a 500 bp fragment of the secA gene has been performed on 35 phytoplasma isolates representing 10 of the 16S rDNA groups. The lineages obtained coincide with those delineated by 16S rDNA phylogenetic analysis but much greater genetic variability was evident. In addition, phylogenetic analysis based on part of the 23S rDNA gene combined with T-RFLP (terminal restriction fragment length polymorphism) analysis of this region supports the lineages. The results clearly indicate a significant delineation between the 16SrI and 16SrXII phytoplasmas and those in other 16Sr groups, and support the proposals that the coconut lethal yellowing type phytoplasmas should be divided into three ‘Candidatae species’.
منابع مشابه
Phytoplasma phylogenetics based on analysis of secA and 23S rRNA gene sequences for improved resolution of candidate species of 'Candidatus Phytoplasma'.
Phytoplasma phylogenetics has focused primarily on sequences of the non-coding 16S rRNA gene and the 16S-23S rRNA intergenic spacer region (16-23S ISR), and primers that enable amplification of these regions from all phytoplasmas by PCR are well established. In this study, primers based on the secA gene have been developed into a semi-nested PCR assay that results in a sequence of the expected ...
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