A new phytoplasma associated with little leaf disease in azalea: multilocus sequence characterization reveals a distinct lineage within the aster yellows phytoplasma group

作者：Wei, Wei; Cai, Hong; Jiang, Yi; Lee, Ing-Ming; Davis, Robert E.; Ding, Yang; Yuan, Enping; Chen, Hairu; Zhao, Yan^*

来源：Annals of Applied Biology, 2011, 158(3): 318-330.

DOI：10.1111/j.1744-7348.2011.00468.x

• Azalea little leaf disease
• gene lineage
• multilocus sequence analysis
• phytoplasma
• Rhododendron spp

An azalea little leaf (AzLL) disease characterised by abnormally small leaves, yellowing and witches'-broom growth symptoms was observed in suburban Kunming, southwest China. Transmission electron microscopic observations of single-membrane-bound, ovoid to spherical bodies in phloem sieve elements of diseased plants and detection of phytoplasma-characteristic 16S rRNA gene sequence in DNA samples from diseased plants provided evidence linking the disease to infection by a phytoplasma. Results from restriction fragment length polymorphism, phylogenetic and comparative structural analyses of multiple genetic loci containing 16S rRNA, rpsS, rplV, rpsC and secY genes indicated that the AzLL phytoplasma represented a distinct, new 16Sr subgroup lineage, designated as 16SrI-T, in the aster yellows phytoplasma group. The genotyping also revealed that the AzLL phytoplasma represented new rp and secY gene lineages [rp(I)-P and secY(I)-O, respectively]. Phylogenetic analyses of secY and rp gene sequences allowed clearer distinctions between AzLL and closely related strains than did analysis of 16S rDNA.

• 出版日期2011
• 单位云南农业大学