FAMILY IV. PSEUDOMONADACEAE 



163 



Gelatin: Liquefied. 



Beef extract agar colonies: Small, circu- 

 lar, smooth, flat or raised with regular 

 margins, white to pale yellow. 



Beef broth: Moderate clouding. 



Milk: Clearing after coagulation. Litmus 

 red. 



Uschinsky's solution: Good growth. 



Cohn's solution: Poor growth. 



Potato: Growthsmooth, copious andolive- 

 bufT. 



Nitrites produced from nitrates. 



Indole produced. 



Hydrogen sulfide produced. 



Acid and gas from glucose, sucrose and 

 glycerol. Acid from lactose. 



Starch hydrolyzed. 



Temperature relations: Optimum, 32° C. 

 Growth above 36° C. and below 2° to 8° C. 



Optimum pH, between 6 and 7; no growth 

 below pH 3. 



Aerobic. 



Relationship to other species: This spe- 

 cies closely resembles the specie.s placed in 

 Aeromonas Kluyver and van Niel. 



Source : Isolated from leaf spot of Jimson 

 weed. Datura spp. 



Habitat: Pathogenic on Datura metel, D. 

 meteloides, D. inermis, tomato and petunia. 



20. Xaiithomona.s holcicola (Elliott, 

 1930) Starr and Burkholder, 1942. {Bac- 

 terium holcicola Elliott, Jour. Agr. Res., 40, 

 1930, 972; Starr and Burkholder, Phytopath. 

 32, 1942, 600.) 



hol.ci'co.la. Gr. holcus kind of grass; 

 M.L. mas.n. Holcus generic name of velvet 

 grass and sorghum; L. v. cola to dwell ; M.L. 

 fem.n. holcicola, Holcus dweller. 



Rods 0.75 by L58 microns. Motile with 

 1 or 2 polar flagella. Encapsulated. Gram- 

 negative. 



Gelatin: Liquefied. 



Beef -infusion peptone agar colonies: 

 Round, umbonate, glistening, smooth, 

 translucent to opaque, wax-yellow, buty- 

 rous. 



Broth: Trace of growth in 24 hours. Later 

 turbid with a slight ring. 



Milk: Casein precipitated and peptonized. 

 Alkaline. 



Nitrite production doubtful. 



Indole not produced. 



Hydrogen sulfide produced. 



Lipolytic (Starr and Burkholder, loc. 

 cit.). 



Acid but no gas from sucrose. 



Starch hydrolyzed. 



Temperature relations: Optimum, be- 

 tween 28° and 30° C. Minimum, 4° C. Maxi- 

 mum, between 36° and 37° C. 



pH range for growth: pH 5.5 to 9.0. Opti- 

 mum pH, between 7.0 and 7.5. 



Source: Isolated from many collections of 

 sorghum leaves showing a streak disease. 



Habitat: Pathogenic on leaves of Holcus 

 sorghum and H. halepensis. 



21. Xanthomonas incanae (Kendrick 

 and Baker, 1942) Starr and Weiss, 1943. 

 (Phytomonas incanae Kendrick and Baker, 

 California Bull. 665, 1942, 10; Starr and 

 Weiss, Phytopath., 33, 1943, 316.) 



in.ca'nae. L. adj. incanus hoary, gray; 

 from host Matthiola incana. 



Rods 0.4 to 0.8 by 0.6 to 2.5 microns. 

 Motile with a polar flagellum. Gram-nega- 

 tive. 



Gelatin: Liquefied. 



Beef extract agar colonies: Round, 

 smooth, convex or pulvinate, glistening, 

 margin entire, picric-yellow to amber color. 



Broth: Turbid. 



Milk: No coagulation. A clearing of 

 the medium. 



Nitrites not produced from nitrates. 



Indole not produced. 



Lipolytic (Starr and Burkholder, Phy- 

 topath., 32, 1942, 600). 



Acid but no gas from glucose, lactose, 

 sucrose, mannitol, d-galactose, xylose, 

 d-mannose, raffinose, trehalose and glycerol. 

 No acid from maltose, 1-arabinose or 

 rhamnose. 



Starch not hydrolyzed. Starch hydrolyzed 

 (Burkholder). 



Pectate medium liquefied. 



Tolerates 3 per cent salt. 



Growth in beef broth at pH 4.4. 



Aerobic. 



Distinctive characters: Causes a disease 

 of flowering stock but not of cabbage. Dif- 

 fers from Xanthomonas campestris in that it 

 does not utilize 1-arabinose or maltose. 



Source: Four isolates from diseased plants 

 of Matthiola incana. 



