132 



ORDER I. PSEUDOMONADALES 



Hydrogen sulfide produced. 



Acid but no gas from glucose, lactose, mal- 

 tose, sucrose and mannitol. 



Aerobic, facultative. 



Source: Isolated from the black rust of 

 tobacco. 



Habitat: Pathogenic on tobacco, Nico- 

 tiana tnbacum. 



89. Pseudomoiia.s riniaefaciens Koning, 

 1938. (Chron. Bot., 4, 1938, 11; Meded. 

 Phj-top. Labor, Willie Comm. Scholt., 14, 

 1938, 24.) 



ri.mae.fa'ci.ens. L. rima a crack; L. v. 

 facio to make; M.L. part. adj. riniaefaciens 

 making cracks. 



Rods 0.6 to 2.4 microns in length. Motile 

 with 1 to 3 flagella. Gram-negative. 



Yellow-green, fluorescent, water-soluble 

 pigment produced in culture. 



Gelatin: Liquefied. 



Agar colonies: Round, conve.x, smooth, 

 somewhat granular with hyaline edge. 



Broth: Turbid. Surface growth with a 

 sediment in a few days. 



Milk: Alkaline and clears. 



Nitrites not produced from nitrates. Pep- 

 tone, asparagin, urea, gelatin, nitrates and 

 ammonium salts are sources of nitrogen. 



Hydrogen sulfide not produced. 



Indole production slight. 



Growth with the following carbon sources 

 plus NO3 : glucose, sucrose, glycerol, suc- 

 cinates, malates, citrates and oxalates. Less 

 growth with mannitol, fructose, galactose, 

 lactose and salicylate. Acid is produced 

 from the sugars. No growth with dextrin, 

 inulin, maltose, lactose, rhamnose, salicin, 

 tartrates, acetates or formates. 



Starch not hydrolyzed. 



Aerobic. 



Temperature relations: Optimum, 25° C. 

 Very slow growth at 14° C. Maximum, about 

 37° C. Thermal death point between 42° and 

 48° C. 



Relationship to other species: This may 

 be Pseudomonas syringae since the charac- 

 ters are the same and both organisms can 

 infect Impatiens sp. Pseudomonas syringae 

 infects poplars (Elliott, Bacterial Plant 

 Pathogens, 1930, 218). 



Source: Strains of the pathogen isolated 



from poplar cankers in France and in the 

 Netherlands. 



Habitat: Pathogenic on Populus braban- 

 tica, P. trichocarpa and P. candicans. 



90. Pseudomonas striafaciens (Elliott, 

 1927) Starr and Burkholder, 1942. (Bac- y 

 terium striafaciens Elliott, Jour. Agr. Res., 

 35, 1927, 823; Starr and Burkholder, Phyto- 

 path., 32, 1942, 601.) 



stri.a.fa'ci.ens. L. stria a furrow; M.L. 

 part. adj. striafaciens furrowing. 



Rods 0.66 by 1.76 microns. Motile with 

 one to several flagella. Encapsulated. Gram- 

 negative. 



Green fluorescent pigment produced. 



Gelatin: Liquefied. 



Beef -peptone agar colonies: White, 

 raised, margins entire or slighth' undulat- 

 ing. 



Broth: Clouding in layers. Ring and slight 

 pellicle. 



Milk: Alkaline, sometimes a soft curd 

 w^hich digests or clears. 



Slight production of nitrites from ni- 

 trates. 



Indole not produced. 



Acid but no gas from glucose, fructose 

 and sucrose. No acid from lactose, maltose, 

 glycerol or mannitol. 



Starch: Hydrolysis slight. 



Optimum temperature, 22° C. 



Optimum pH, between 6.5 and 7.0. 



Aerobic. 



Distinctive characters: Differs from 

 Pseudomonas coronafaciens in that the cells 

 are somewhat smaller and the pathogen pro- 

 duces a streak on oat blades instead of a 

 halo spot. 



Source : Forty cultures isolated from oats 

 gathered in various parts of America. 



Habitat: Pathogenic on cultivated oats 

 and, to a slight degree, on barley. 



91. Pseudomonas tabaci (Wolf and 

 Foster, 1917) Stevens, 1925. {Bacterium ta- 

 bacum (sic) Wolf and Foster, Science, 46, 

 1917, 362; also Jour. Agr. Res., 12, 1918, 449; 

 Stevens, Plant Disease Fungi, New York, 

 1925, 36.) 



ta.ba'ci. M.L. noun iabacum tobacco; 

 M.L. gen. noun tabaci of tobacco. 



