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MANUAL OF DETERMINATIVE BACTERIOLOGY 



Among the synonyms listed in previous 

 editions of the Manual has been Poly- 

 monas tumefaciens Lieske, Cent. f. 

 Bakt., I Abt., Orig., 108, 1928, 118. This 

 is only a partial synonym, however, as 

 its author described it as the cause of 

 animal and human cancer, of which he 

 regarded crown-gall of plants as merely 

 a phase : for the origin of this theory, see 

 Smith and Townsend, Sci., N.S. 25, 1907, 

 671, and Smith, Jour. Cancer Res., 7, 

 1922, 1-105. 



Description taken from the following: 

 Riker, Banfield, Wright, Keitt and 

 Sagen, Jour. Agr. Res., 41, 1930, 507; 

 Sagen, Riker and Baldwin, Jour.Bact., 

 £8, 1934, 571; Hendrickson, Baldwin and 

 Riker, Jour. Bact., 28, 1934, 597. 



Rods: 0.7 to 0.8 by 2.5 to 3.0 microns, 

 occurring singly or in pairs. Capsules. 

 Motile with 1 to 4 flagella. Gram- 

 negative. 



Agar colonies: Small, white, circular, 

 smooth, glistening, translucent, entire. 



Broth: Slightly turbid, with thin pel- 

 licle. 



Litmus milk: Slow coagulation. Lit- 

 mus reduced. Neutral to alkaline. 



Nitrites produced from nitrates to a 

 very slight extent. 



Indole: Slight amount. 



Slight acid from glucose, fructose, 

 arabinose, galactose, mannitol and salicin. 



Starch not hydrolyzed. 



Optimum temperature 25° to 28°C. 



Facultative anaerobe. 



Distinctive characters : Causes a gall 

 formation parenchymatous in character 

 which because of its soft nature is sub- 

 ject to injury and decay. 



Agrobacterium tumefaciens strongly ab- 

 sorbs Congo red and aniline blue in con- 

 trast to little or no absorption by A. 

 rhizogenes. A. tumefaciens makes abun- 

 dant growth on sodium selenite agar and 

 calcium glycerophosphate medium with 

 mannitol in contrast to no growth or a 

 very slight trace by A. rhizogenes (Hen- 

 drickson et al., Jour. Bact., 28, 1934, 

 597). 



Source: Isolated from galls on plants. 



Habitat : Causes galls on Paris daisy 



and cross-inoculable on over 40 families. 



2. Agrobacterium rhizogenes (Riker 

 et al.) Conn. (.Bacterium rhizogenes 

 Riker, Banfield, Wright, Keitt and Sagen, 

 Jour. Agr. Res., 41, 1930, 536; Phyto- 

 monas rhizogenes Riker et al., ibid., 

 536; Pseudomonas rhizogenes Riker et 

 al., ibid. 536; Conn, Jour. Bact., 44, 1942, 

 359.) From Greek, rhiza, root; genes, 

 producing. 



Rods: 0.4 by 1.4 microns, occurring 

 singly. Motile with one to 4 flagella. 

 Encapsulated. Not acid-fast. Gram- 

 negative. 



Gelatin : No liquefaction. 



Agar colonies : Circular, smooth, con- 

 ve-x, finely granular; optical characters, 

 translucent through gray to almost white. 



Agar slant: Moderate, filiform, trans- 

 lucent, raised, smooth, slimy. 



Broth: Turbid, with heavy pellicle. 



Litmus milk: Acid, slow reduction. 



Indole not formed. 



Nitrites not produced from nitrates. 



Acid but not gas from arabinose, xy- 

 lose, rhamnose, glucose, galactose, man- 

 nose, maltose, lactose, salicin and ery- 

 thritol. No acid or gas from fructose, 

 sucrose, raffinose, melezitose, starch, 

 dextrin, inulin, aesculin, dulcitol or man- 

 nitol. 



Starch not hydrolyzed. 



Optimum temperature 20° to 28°C. 



Aerobic. 



Distinctive characters : Agrobacterium 

 rhizogenes differs from Agrobacterium 

 tumefaciens by stimulating root forma- 

 tion instead of soft parenchymatous 

 crown galls. A. rhizogenes lacks ability 

 of A. tumefaciens to utilize simple 

 nitrogenous compounds as KNO3. A. 

 rhizogenes absorbs congo red and brom 

 thymol blue slightly and aniline blue not 

 at all. Will not grow on sodium selenite 

 agar (see A. tumefaciens for response 

 to same materials). Does not infect 

 tomato . 



