FAMILY HHIZOBIACEAE 



225 



hium frankii var. majus and var. mi- 

 nus Schneider (?), Rhizohium nodosum 

 Schneider (?), Rhizohium dubium 

 Schneider (?), Bui. Torrej' Bot. Club, 

 19, 1892, 213; Rhizohium sphaeroides 

 Schneider (?), Ber. deut. bot. Gesell., 12, 

 1894, 16; Bacillus tuberigenus Gonner- 

 mann and Micrococcus tuberigenus Gon- 

 nermann, Landw. Jahrb., 33, 1894, 654, 

 657, are thought bj" Fred, Baldwin and 

 McCoy (University of Wisconsin, Stud- 

 ies in Science, Xo. 5, 1932, 140) not to be 

 true noduJe organisms and to be too 

 poorly described to be recognizable to- 

 day ; Rhyzobium pasteurianum Maze (all 

 species), Ann. Inst. Pasteur, 13, 1899, 

 146; Pseudorhizobium ramosnm Hartleb 

 (?) (Chem. Zeit., U, 1900, 887) (used 

 for noninfective culture claimed b}" 

 Stutzer (Mitt. Landw. Inst. Breslau, /, 

 Heft 3, 1900, 63) to be }>;enuine root nod- 

 ule organism) ; Rhizohium radicicola 

 Hiltner and Stormer (several species) 

 and Rhizohium heijerinckii Hiltner and 

 Stormer (from lupine, serradella and soy 

 bean), Arb. Biol. Abt. f. Land-u. Forst- 

 wirthschaft a. K. Gesundheitsamte, 3, 

 1903, 269; Pseudomonas radicicola ]\Ioore 

 (all species), U. S. Dept. Agr. Bur. 

 Plant Ind., Bui. 71, 1905, 27; Rhizomonas 

 heijerinckii Orla-Jensen and Rhizomonas 

 radicicola Orla-Jensen (see Hiltner and 

 Stormer), Cent. f. Bakt., II Abt., 22, 

 1909, 328; Bacillus or Bacterium radici- 

 cola Lohnis and Hansen (peritrichous 

 species). Jour. Agr. Research, 20, 1921, 

 554 ; Rhizohium radicicolum Bergej' et al. , 

 Manual, 1st ed., 1923, 40 (monotrichous 

 species) ; Rhizohium loti Dangeard (from 

 lotus), Rhizohium simplex Dangeard 

 (from sainfoin), Rhizohium torulosum 

 Dangeard (from Scotch broom), Le 

 Botaniste, Ser. 16, 1926, 195-197. 



Rods: 0.5 to 0.9 by 1.2 to 3.0 microns. 

 Motile with peritrichous flagella. Bac- 

 teroids commonly irregular with x, y, 

 star- and club-shaped forms. Vacuolate 

 forms predominate. Gram-negative. 



Growth on mannitol agar is rapid, with 

 tendency to spread. Streak is raised, 



glistening, semi-translucent, white, slimy 

 and occasionally viscous. Considerable 

 gum is formed. 



Slight acid production from glucose, 

 galactose, mannose, lactose and maltose. 



Aerobic. 



Optimum temperature 25°C. 



Source : Root nodules on Lathyrus, 

 Pisum (poa), Vicia (vetch) and Lens 

 (lentil). 



Habitat : Widely distributed in soils 

 where the above mentioned legumes are 

 grown 



2. Rhizobiumphaseoli Dangeard. (Le 

 Botaniste, Ser. 16, 1926, 197.) From 

 Latin, phascolus, bean; M. L. Phaseolus, 

 a generic name. 



Rods : Motile with peritrichous fla- 

 gella. Bacteroids are usuallj^ rod-shaped, 

 often vacuolated with few branched 

 forms. Usually smaller than in Rhizo- 

 hium leguminosariim and R. trifolii. 

 Gram -negative. 



Growth on mannitol agar is rapid with 

 tendency to spread. Streak inoculation 

 is raised, glistening, semi-translucent, 

 white, slimJ^ Occasionally mucilagi- 

 nous but this character is not so marked 

 as in Rhizohium trifolii. 



Very slight acid formation from glu- 

 cose, galactose, mannose, sucrose and 

 lactose. 



Aerobic. 



Optimum temperature 25 ''C. 



Source : Root nodules of Phaseolus 

 vulgaris (kidney bean), P. ayigustifolius 

 (bean) and P. multiflorus (scarlet run- 

 ner). (Burrill and Hansen, 111. Agr. 

 Exp. Sta. Bui. 202, 1917, 137.) 



Habitat : Widely distributed in the 

 soils in which beans are grown. 



3. Rhizobium trifolii Dangeard. (Le 

 Botaniste, Ser. 16, 1926, 191.) From 

 M. L. Trifolium, a generic name. 



Rods : Motile with peritrichous fla- 

 gella. Bacteroids from nodules are pear- 

 shaped, swollen and vacuolated. Rarely 

 X and y shapes. Gram-negative. 



