Page:Bergey's manual of determinative bacteriology.djvu/154

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132
ORDER I. PSEUDOMONADALES

Hydrogen sulfide produced.

Acid but no gas from glucose, lactose, maltose, sucrose and mannitol.

Aerobic, facultative.

Source: Isolated from the black rust of tobacco.

Habitat: Pathogenic on tobacco, Nicotiana tabacum.


89. Pseudomonas rimaefaciens Koning, 1938. (Chron. Bot., 4, 1938, 11; Meded. Phytop. 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. rimaefaciens 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, convex, 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. Peptone, 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, succinates, 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 characters 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 brabantica, P. trichocarpa and P. candicans.


90. Pseudomonas striafaciens (Elliott, 1927) Starr and Burkholder, 1942. (Bacterium striafaciens Elliott, Jour. Agr. Res., 35, 1927, 823; Starr and Burkholder, Phytopath., 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 slightly undulating.

Broth: Clouding in layers. Ring and slight pellicle.

Milk: Alkaline, sometimes a soft curd which digests or clears.

Slight production of nitrites from nitrates.

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 produces 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 tabacum (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 tabacum tobacco; M.L. gen.noun tabaci of tobacco.