1922] 



ROSEN — A BACTERIAL DISEASE OF FOXTAIL 335 



In 1887 Burrill described a disease of broom-corn and sorghum 

 which he attributed to bacteria. Two years later, Kellerman 

 and Swingle (I, '89), under the name of "sorghum blight," pub- 

 lished an account of a disease which they considered the same as 

 Burrill's; they also accepted and seemingly substantiated his 

 work on the pathogenicity of the organism which he had named 

 Bacillus Sorghi. Several other investigators before and after 

 Burrill's time have worked on red spots of sorghum, but to this 

 day we have little exact information on the disease. Thus Pal- 

 merie and Comes in 1883 decided that red discolorations of sor- 

 ghum were due to yeasts and bacteria; Radais in 1899 concluded 

 that sorghum blight was due to yeasts; and Busse (I, '05), in a 

 rather extensive paper, showed that various causes can produce 

 reddening of sorghum. Concerning any bacterial disease of 

 sorghum, Busse concluded that there was no specific bacterial 

 pathogen involved, that the bacteria which have been found 

 within the tissues were merely facultative parasites which en- 

 tered by means of injuries induced by insects and other agents 

 and that Bacillus Sorghi was an organism of this sort. The writer 

 does not intend to go extensively into this disease, or rather 

 group of diseases, at this time; suffice it to say that as far as 

 the written descriptions of B. Sorghi are concerned the organism 

 cannot be identified. While apparently accepting Burrill's or- 

 ganism in an early publication (Smith and Hedges, I, '05) Smith 

 handles it with great caution in other publications (I, '05, p. 

 66, p. 92, pi. 20 [opposite p. 150] ; '11, p. 62 and 63), not defi- 

 nitely rejecting it but substituting another name, Bacterium An- 

 dropogoni. Smith's complete account of B. Andropogoni fol- 

 lows: "It is non-sporiferous, polar-flagellate (1-3), and white on 

 culture media, forming small circular colonies on agar-poured 

 plates. It is aerobic, non-liquefying, non-reducing (nitrates)." 

 Manifestly this preliminary description also is so incomplete 

 that it is impossible to make any adequate comparison with an 

 unidentified organism. We may note, however, that the foxtail 

 organism possesses similar characters with the exception that it 

 has but a single polar fiagellum and is a marked nitrate reducer. 

 The writer's preliminary studies on a bacterial disease of sor- 

 ghum present in Arkansas indicates that the pathogen there con- 

 cerned is different from the foxtail organism. 



Following the description of a bacterial disease of sorghum 

 Burrill (I, '89) described a bacterial disease of field corn. For 



