Neighbor-joining phylogeny for partial 16S rRNA sequences (alignment length, 1,050 bp) showing relationships between rhizogenic α-Proteobacteria isolated from RMA cucumber and tomato crops as well as a panel of representative strains. Footnotes: a, numbers on the dendrogram represent the percentages of grouping confidence calculated by bootstrap analysis (100 bootstrap replicates); b, GenBank accession numbers; c, strains in bold are the nine rhizogenic α-Proteobacteria strains plus two rhizogenic A. radiobacter strains isolated from RMA cucumber crops.