PSEUDOMONAS FLAVESCENS SP-NOV, ISOLATED FROM WALNUT BLIGHT CANKERS

Two pseudomonad strains that produce a yellow cellular pigment, in addition to a diffusible fluorescent pigment on Kings medium B, were isolated from cankers on walnut trees. Biochemical properties, such as a positive oxidase reaction, a negative arginine dihydrolase reaction, and the production of a fluorescent pigment; in addition to the results of an extensive nutritional characterization study and DNA-DNA hybridization experiments, indicated that these strains belong to a new Pseudomonas rRNA group I species. This conclusion was supported by the results of a determination of the sequence of the PCR-amplified 16S rRNA gene and a comparison with the 16S rRNA genes of other bacterial species. The genomic DNAs of the strains had a base composition of 63 mol% Gf C. The name Pseudomonas flavescens sp. nov. is proposed. Strain B62 (= NCPPB 3063) is the type strain of the species.