Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Rhizobium skierniewicense sp. nov., isolated from tumours on chrysanthemum and cherry plum.

Abstract

Three isolates of Gram-negative, rod-shaped, non-spore-forming bacteria were recovered from galls on chrysanthemum (Chrysanthemum L.; Ch11T, Ch12) and cherry plum (Prunus cerasifera var. divaricata; AL9.3). All three isolates were able to cause crown galls on various plant species. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the three isolates were probably identical (100% sequence similarity) and closely related to Rhizobium rubi (99.6%), Rhizobium radiobacter (98.7%) and Rhizobium larrymoorei (98.1%). Similar analysis based on the housekeeping genes glnA, gyrB and rpoB also indicated that the novel isolates were identical and closely related to R. rubi. The major cellular fatty acids of strain Ch11T were C18:1ω7c (62.1%), summed feature 2 (comprising C12:0 aldehyde, iso-C16:1 I and/or C14:0 3-OH; 10.8%), summed feature 3 (comprising C16:1ω7c and/or iso-C15:0 2-OH; 7.7%) and C10:0 3-OH (7.5%). However, the DNA-DNA relatedness between Ch11T and R. rubi LMG 156T was only 48% and, unlike phylogenetically related established Rhizobium species, the novel isolates were able to utilize β-hydroxybutyric acid but not L-fucose. Based on the phylogenetic and phenotypic evidence, the isolates are considered to represent a single novel species of the genus Rhizobium, for which the name Rhizobium skierniewicense sp. nov. is proposed; the type strain is Ch11T (=LMG 26191T=CFBP 7420T).