FUNGI AFFECTING BROOM CORN AND 



SORGHUM 



The Sorghum Blight 



Bacillus sorghi 



This disease is caused by bacteria, and so is some- 

 what similar to the bacterial disease of corn already dis- 

 cussed. It occurs upon both sorghum and broom corn, 

 and is especially characterized by the red markings it 

 produces upon affected plants. Its nature was first 

 worked out by Professor T. J. Biirrill, who gives the 



follow^ing description of the external manifestations of 

 its presence : 



^'Sometimes tlie ai^i^earance of injury is noticeable 

 upon 3'oung j^lants. They grow very slowly, are slender 

 and yellowish in color, and are easily pulled from the 

 ground. The lower leaves die, having previously shown 

 discolored (yellow or red, mostly the latter) patches on 

 various parts of their surface. Not unfrequently these 

 conditions prevail in special areas of the field; perhai^s 

 several acres, not apparently different in composition of 

 soil, condition of drainage, etc., will have throughout 

 their extent this dwarfed and sickly crop, while the rest 

 of the plantation remains healthy and vigorous. More 

 often the evidence of disease appears, to a greater or less 

 extent, over the entire field, all, or an exceedingly varia- 

 ble proportion of the jDlant suffering. Not unfrequently 

 stalks, four or five feet high, can be lifted with ease from 

 the soil, the roots being mostly dead and rotten. 



'^IJpon the aerial parts the conspicuous evidence of 

 disease, aside from the smaller size of affected plants, is 



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