II. Not pathogenic to plants. A. From soil. Grows on potato. Nitrates completely assimilated; test for nitrites may be negative. 6. Agrobacieriion radiohacter . B. From marine mud. Does not grow on potato. Nitrites produced from nitrates. 7. Agrohacterium stellulatum. 1. Agrobacteriuni tumefaciens (Smith and Townsend, 1907) Conn, 1942. {Bacterium tumefaciens Erw. Smith and Townsend, Science, 25 (N.S.), 1907, 672; Conn, Jour. Bact., 44, 1942, 359.) tu.me.fa'ci.ens. L. part. adj. tumefaciens tumor-producing. Description taken from Riker, Banfield, Wright, Keitt and Sagen (Jour. Agr. Res., 41, 1930, 507), Sagen, Riker and Baldwin (Jour. Bact., £8, 1934, 571) and Hendrick- son, Baldwin and Riker (Jour. Bact., 28, 1934, 597). Rods, 0.7 to 0.8 by 2.5 to 3.0 microns, oc- curring singly or in pairs. Encapsulated. Motile by means of 1 to 4 flagella. Gram- negative. Agar colonies: Small, white, circular, smooth, glistening, translucent, entire. Broth: Slightly turbid, with thin pellicle. Litmus milk: Slow coagulation. Litmus reduced. Neutral to alkaline. Indole production slight. Slight acid from glucose, fructose, arabi- nose, galactose, mannitol and salicin. Starch not hydroh^zed. Nitrites produced from nitrates to a very slight e.xtent. Optimum temperature, between 25° and 28° C. Facultative anaerobe. Distinctive characters: Causes a gall formation, parenchymatous in character, which, because of its soft nature, is subject to injury and decay. Agrobacteriuni tumefaciens strongly ab- sorbs Congo red and aniline blue in contrast to little or no absorption by A. rhizogenes. A. tumefaciens makes abundant growth on sodium selenite agar and calcium glj'cero- phosphate medium with mannitol in con- trast to no growth or a very slight trace by A. rhizogenes (Hendrickson et al., loc. cit.). Comment: A variety of this species that causes galls on blueberry has been de- scribed by Demaree and Smith (Phyto- path., .^^, 1952, 88). Source: Isolated from galls on plants. Habitat: Causes galls on Paris daisy and is cross-inoculable on over 40 families. 2. Agrobacteriuni gypsophilae (Brown, 1934) Starr and Weiss, 1943. {Bacterium gypsophilae Brown, Jour. Agr. Res., 48, 1934, 1109; Starr and Weiss, Phytopath., 33, 1943, 316.) gyp.so'phi.lae. Gr. noun gypsus chalk; Gr. adj. philus loving; M.L. fem.n. Gyp- sophila chalk-lover, generic name; M.L. gen. noun gypsophilae of Gypsophila. Rods, 0.2 to 0.8 by 0.4 to 1.4 microns. Mo- tile by means of 1 to 4 flagella. Encapsu- lated. Gram-negative. Gelatin: Liquefaction slow, beginning after 1 month. Beef -infusion agar colonies: Circular, Naples-yellow, smooth or rough, butyrous. Broth: Turbid in 24 hours. Milk: Coagulation and peptonization. Indole not produced. Hydrogen sulfide: A trace may be pro- duced. Acid but no gas from glucose, sucrose, maltose, mannitol and glycerol. No acid from lactose. Starch not hydrolyzed. Nitrites produced from nitrates. Aerobic, facultative. Distinctive characters : Differs from Xan- ihomonas beticola in starch hydrolj^sis and hydrogen sulfide production; further- more, these two species cannot be cross- inoculated. Source: Isolated from several galls on Gypsophila. Habitat: Produces galls in Gypsophila paniculata and related plants.
