Plate V. — Diseases of sweet potatoes, a, A section through a 

 sweet potato sliovving the blackened ring just below the surface 

 caused by the stem-rot fungus, b, A sweet potato plant showing 

 the characteristic symptoms of stem-rot. c, Sweet potato black-rot. 

 Small sweet potato plant showing the characteristic blackening of 

 the underground part of the stem, d. Soft-rot. A sweet potato 

 showing the moldy growth of the fungus causing soft-rot. e. 

 Soil-splotch. 



