- Volume 58, Issue 6, 2008

Phytoplasmas were detected in cactus (Opuntia species) plants exhibiting witches'-broom disease symptoms in Yunnan Province, south-western China. Comparative and phylogenetic analyses of 16S rRNA gene sequences indicated that an overwhelming majority of the cactus-infecting phytoplasmas under study belonged to the peanut witches'-broom phytoplasma group (16SrII). Genotyping through use of computer-simulated restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes revealed a remarkable genetic diversity among these cactus-infecting phytoplasma strains. Based on calculated coefficients of RFLP pattern similarities, seven new 16SrII subgroups were recognized, bringing the total of described group 16SrII subgroups to 12 worldwide. Geographical areas differed from one another in the extent of genetic diversity among cactus-infecting phytoplasma strains. The findings have implications for relationships between ecosystem distribution and the emergence of group 16SrII subgroup diversity.

On the basis of 16S rRNA gene sequence analysis and several key phenotypic features, it was ascertained that the cultures cited as the type strain of the species Pectinatus portalensis, CECT 5841T and LMG 22865T, do not conform to the description, [Gonzalez, J. M., Jurado, V., Laiz, L., Zimmerman, J., Hermosin, B. & Saiz-Jimenez, C. (2004). Antonie van Leeuwenhoek 86, 241–248]. The type strain does not exist in any other established culture collection or with the authors who described this species. Therefore, it cannot be included in any scientific study. It is proposed that the Judicial Commission place the name Pectinatus portalensis on the list of rejected names if a suitable replacement type strain is not found or a neotype is not proposed within two years following the publication of this Request for an Opinion.