fa:mily pseudomoxadaceae 



129 



Starch hydroh-sis feeble. 



Optimum temperature 25°C. 



Source : Isolated in England from 

 brown-spot of cultivated mushrooms. 



Habitat : Pathogenic on cultivated 

 mushrooms. 



104. Pseudomonas xanthochlora 



(Schuster) Stapp. {Bacterium xantho- 

 chlorum Schuster, Arbeit, a. d. Kaiserl. 

 Biolog. Anstalt. f. Land. u. Forstw., 8, 

 1912, 452; Phytomonas xanthochlora Ber- 

 gey et al., Manual, 1st ed., 1923, 180; 

 Stapp, in Sorauer, Handbuch der Pflan- 

 zenkrankheiten, 2, 5 Auf., 1928, 213.) 

 From Gr. xanthus, yellow; chlorus, green. 



Description from FJrw. Smith, Bacteria 

 in Rel. to Plant Dis., 5, 1914, 272. 



Rods: 0.75 to 1.5 by 3.0 microns. Mo- 

 tile with 1 to 3 fiagella. Gram-negative. 



Green fluorescent pigment produced in 

 culture. 



Gelatin: Slow liquefaction. 



Agar colonies : Circular, slightly raised, 

 yellow -white. 



Broth: Strong clouding in 24 hours. 

 A white pellicle. 



Milk : Slow coagulation and clearing. 



Nitrites are produced from nitrates. 



Indole is produced after 10 days. 



Hydrogen sulfide produced slowlj-. 



Acid but not gas from glucose and 

 galactose. 



Optimum temperature 27"C. Maxi- 

 mum 44°C. Minimum 2'C. 



Source: Isolated from rotting potato 

 tubers in Germany. 



Habitat : Pathogenic on potato tubers 

 and a number of unrelated plants. 



105. Pseudomonas rhizoctonia (Thom- 

 as) comb. nov. {Aplanobacter rhizoctonia 

 Thomas, Ohio Agr. Exp. Sta. Bull. 359, 

 1922, 211 ; Bacterium rhizoctonia Stapp, 

 in Sorauer, Handbuch der Pflanzenkrank- 

 heiten, 2, 5 Auf., 1928, 290; Phytomonas 

 rhizoctonia Burkholder, Ph3'topath., 20, 

 1930, 7.) From Gr. rhizo, root; ctoiuis, 

 murder. 



Rods: 0.5 to 0.85 by 1.4 to 1.9 microns. 

 Non-motile. Gram-negative. 



Green fluorescent pigment produced in 

 culture. 



Gelatin: Liquefaction. 



Nutrient agar colonies: Greenish-yel- 

 low, later olive-buff, circular, raised, 

 slightly viscid. 



Broth: Turbid, pyrite yellow. 



Milk: Alkaline; clears. 



Nitrites are produced from nitrates. 



Indole reaction very slight. 



No HoS formed. 



Starch : Potato starch slighth- hy- 

 drolyzed. 



Growth in 8 per cent salt. 



Optimum temperature 25° to 27''C. 

 Maximum 38°C. Minimum 0°C. 



Source : Isolated from roots of lettuce 

 showing the rosette disease. 



Habitat : Pathogenic on roots of let- 

 tuce. 



106. Pseudomonas barker! (Berridge) 

 Clara. (Bacillus of pear blossom dis- 

 ease. Barker and Grove, Ann. Appl. Biol., 



I, 1914, 94; Barker and Grove's organism, 

 Doidge, Ann. Appl. Biol., 4, 1917, 50; 

 B. barkeri Berridge, Ann. Appl. Biol., 



II, 1924, 73; Phytomonas barkeri Bergey 

 et al.. Manual, 3rd ed., 1930, 265; Bac- 

 terium barkeri Elliott, Bacterial Plant 

 Pathogens, 1930, 95; Clara, Science, 75, 

 1934, 11.) Named for B. T. P. Barker 

 who first reported the species. 



Description from Doidge (loc. cit.). 



Rods : 0.5 to 0.8 bj^ 2 to 4 microns. 

 Motile with 1 to 4 polar flagella. Gram- 

 negative (Burkholder), not Gram-posi- 

 tive as stated. 



Green fluorescent pigment produced in 

 culture. 



Gelatin: Liquefaction. 



Agar: Growth is white, feeble, flat, 

 glistening, smooth edged. 



Broth: Slightly turbid in 24 hours. 



Milk: Slowly cleared. 



Nitrites not produced from nitrates. 



Indole not formed unless culture 

 warmed. 



Starch slowly digested. 



Source : Barker made many cultures 



