A Determinative Scheme for the Fluorescent Plant Pathogenic Pseudomonads

Abstract

Summary. The differential value of 15 characteristics was studied for the determination of plant pathogens in the fluorescent group of the genus Pseudomonas. All but 2 of the 161 pathogenic cultures and the 15 nonpathogenic cultures examined could be placed in one of 5 groups on the basis of tests for: oxidase, potato soft rot, arginine dihydrolase, levan production and a hypersensitivity reaction in tobacco leaves. Tests for production of acid from sucrose, nitrate reductase and a lipase for margarine were useful as subsidiary determinants. Aesculin hydrolysis, gelatinase and tyrosinase tests, and the production of a blue fluorescent pigment were of little or no value at the group level, and hydrolysis of Tween 80 and the catalase reaction had no differential value. With the exception of Ps. tolaaii and two cultures of questionable pathogenicity, the pathogens studied could be separated readily from the few nonpathogens studied. A determinative scheme for plant pathogenic fluorescent pseudomonads is proposed to serve until the taxonomy of the group is better understood.

DNA Relatedness among the Pathovar Strains of Pseudomonas syringae subsp. savastanoi Janse (1982) and Proposal of Pseudomonas savastanoi sp. nov.

“…that were either oxidase negative or oxidase positive (P. cichorii), corresponding to groups I through I11 of Lelliott et al (15). Phenon IV was subdivided into five subphena (subphena IVa to IVe), and phenon V was subdivided into subphena Va and Vb.…”

Numerical Analysis and Determinative Tests for Nonfluorescent Plant-Pathogenic Pseudomonas spp. and Genomic Analysis and Reclassification of Species Related to Pseudomonas avenae Manns 1909

“…White Burley) (19). Pectolytic activity was tested on pectate gels at pH 5 and 8 (15); pitting of gels at pH 5 is caused by the action of polygalacturonase, and pitting of gels at pH 8 is caused by pectate lyase.…”

Structure of fuscopeptins, phytotoxic metabolites of Pseudomonas fuscovaginae

“…This pathogen causes necrotic lesions of the flag leaf sheath and reduction of the peduncle elongation which results in the inhibition of inflorescence emergence and sterility of the panicle. Strains of P. fuscovaginae can be distinguished from other fluorescent pseudomonads by several biochemical reactions, as their positive reactions for the oxidase and arginine dihydrolase assays, as well as by serological and pathogenicity tests [2,6].…”