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MANUAL OF DETERMINATIVE BACTERIOLOGY 



Growth on mannitol agar is rapid. Tlic 

 colonies are white becoming turbid with 

 age. Frequently mucilaginous. Streak 

 cultures transparent at first. Growth 

 mucilaginous later flowing down the 

 agar slant and accumulating as a slimy 

 mass at the bottom. Produces large 

 amounts of gum. 



Slight acid production from glucose, 

 galactose, mannose, lactose and maltose. 



Aerobic. 



Optimum temperature 25°C. 



Source : Root nodules of species of 

 Trifolium (clover). 



Habitat: Widely distributed in the 

 soils where clover grows. 



4. Rhizobixim lupini (Schroeter) Eck- 

 hardt, Baldwin and Fred. {Phytomyxa 

 lupini Schroeter, in Cohn, Kryptogamen- 

 Flora von Schlesien, 3, I, 1886, 135; 

 Rhizobium minimum Dangeard, Le Bo- 

 taniste, Ser. 16, 1926, 198; Eckhardt, 

 Baldwin and Fred, Jour. Bact., 21, 1931, 

 273.) From Latin, Lupinus, lupine. 



Rods : Motile with flagella 1 to 4, usually 

 2 or 3. Bacteroids are vacuolate rods, 

 seldom if ever branched. Gram-negative. 



Growth on yeast water, mannitol agar 

 is scant to moderate with alkaline 

 reaction. 



Beef -peptone gelatin : Little growth 

 with extremely slow liquefaction. 



On galactose an alkaline reaction serves 

 to differentiate Rhizobium lupini from 

 all fast-growing rhizobia (R. phaseoli, 

 R. meliloti, R. trifolii, and R. legumino- 

 sarum). An initial alkaline reaction fol- 

 lowed more quickly by an acid reaction 

 on rhamnose and xylose separates R. 

 lupini from slow-growing R. japonicxim 

 and the Rhizobium sp. from cow pea. 



In general Rhizobium lupini produces 

 slight to moderate acidity on pentose 

 sugars and no change or alkaline reaction 

 on hexoses, disaccharides and trisac- 

 charides. 



Litmus milk : No serum zone, no re- 

 duction, and a slight alkaline reaction. 



Meager growth on potato and parsnip 

 slants, and carrot agar. 



Aerobic. 



Optimum temperature 25°C. 



Source : Root nodules on Lupinus 

 (lupine), Serradella and Ornithopus. 



Habitat : Widely distributed in soils 

 in which these legumes grow. 



5. Rhizobium japonicum (Kirchner) 

 Buchanan. (Rhizobacterium japonicum 

 Kirchner, Beitrage zur Biol. d. Pflanzen, 

 7, 1895, 213; Pseudomonas japonica 

 Lohnis and Hansen, Bacterium japoni- 

 cum Lohnis and Hansen, Jour. Agr. 

 Res., 20, 1921, 551; Rhizobium sojae 

 Dangeard, Le Botaniste, Ser. 16, 1926, 

 200; Buchanan, Proc. Iowa Acad. Sci., 

 33, 1926, 81.) From M. L., of Japan. 



Rods : Motile with monotrichous fla- 

 gella. Bacteroids of nodules are long 

 and slender with only occasional branched 

 and swollen forms. Gram-negative. 



Growth on mannitol agar is slow and 

 scant. The streak is slightly raised, 

 glistening, opaque, white, butyrous, with 

 little gum formation. 



Pentose sugars give better growth than 

 the hexoses. 



Little if any acid formed from carbo- 

 hydrates. Acid slowly formed from 

 xylose and arabinose. 



Aerobic. 



Optimum temperature 25°C. 



Source : Root nodules on Soja max 

 (soy bean). 



Habitat : Widely distributed in soils 

 where soy beans are grown. 



6. Rhizobium meliloti Dangeard. (Le 

 Botaniste, Ser. 16, 1926, 194.) From 

 Greek, melilot, a kind of clover; M. L., 

 Melilotus. 



Rods: Motile with peritrichous fla- 

 gella. Bacteroids club-shaped and 

 branched. Gram-negative. 



Growth on mannitol agar is fairly rapid. 

 The streak is raised, glistening, opaque, 

 pearly white, butyrous. Considerable 

 gum is formed. 



