Description of 'Candidatus Phytoplasma meliae', a phytoplasma associated with Chinaberry (Melia azedarach L.) yellowing in South America

F. D. FERNÁNDEZ; GALDEANO, E; M. KORNOWSKI; ARNEODO, J; CONCI, L. R.

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY.

SOC GENERAL MICROBIOLOGY

Lugar: London; Año: 2016 vol. 66 p. 5244 - 5251

1466-5026

China tree yellows phytoplasma (ChTY) is associated with yellowing disease of China tree (Melia azedarach) in Argentina. According to partial 16S rRNA gene analysis, ChTY phytoplasma belongs to 16Sr XIII group, subgroup G. ChTY strains have 98-99% 16S rDNA gene sequence similarity with 16SrXIII-group phytoplasmas, and less than 97.5% when compared to all ´Candidatus Phytoplasma´ described so far, except for the novel "Candidatus Phytoplasma hispanicum". However, ChTY strains are differentiated from the latter by additional molecular and biological attributes. The presence of unique features in 16S rDNA sequence distinguishes ChTY from all currently described ´Candidatus Phytoplasma´ species. In silico RFLP profile of 16S rDNA (1.2kb) and rpLV-rpsC (1.3kb) genes distinguished ChTY in 16SrXIII-G subgroup within 16SrXIIII group. The phylogenetic analyses based on 16S rDNA, rpLV-rpsC and secA gene sequences, in addition to the restricted host range, characteristic symptoms and geographical distribution, confirm that the ChTY collective strains represent a distinct lineage within the phytoplasma clade and support the description of the novel ´Candidatus Phytoplasma meliae´ species with reference strain ChTY-Mo3 (Montecarlo, Argentina).