Nov. I, 1919 



Recent Studies on Sclerotium rolfsii Sacc. 



129 



TablB I. — Hosts affected by Sclerotium rolfsii — Continued 



Though Sclerotium rolfsii attacks a large number of hosts, its virulence 

 is more pronounced on tender plants and growth. As a storage-rot its 

 economic importance can not be overlooked. Pumpkins, squashes, cab- 

 bage, and Irish and sweet potatoes are often seriously affected under 

 storage conditions when the necessary ventilation is lacking. 



NAME OF THE DISEASE 



Plant pathologists are aware of the necessity of standardizing names of 

 plant diseases. The disease here considered seems to have as yet no 

 standard name. Rolfs {12) and Fulton (4) named it "blight," and 

 Earle (i) and Edgerton (5 p. ig) called it " Sclerotium wilt." McClintock 

 (jo) terms it "wilt," and Wolf {20, p. 142-146), working on a peanut 

 disease, named it "Sclerotial rot." Peltier {11) does not give it any par- 

 ticular name, but merely refers to it as a "disease" or "rot." Stevens 

 and Hall {18, p. 259-262) and the writer (19, p. 305) have referred to 

 it as "southern blight." However, this term is misleading, since the 

 bacterial blight of tomatoes named by Halsted (6), in Mississippi, as 

 southern blight is generally accepted now as being caused by Bacillus 

 solonacearum E. F. Sm. Neither would the term "Sclerotium rot" or 

 "wilt" be tenable, since there are several species of Sclerotium fungi 

 known to produce disease in plants. The term "southern Sclerotium 

 rot" is therefore proposed. This will suggest the nature of the causal 

 organism and its southern origin. 



PATHOGENICITY AND RACIAL STRAINS 



Few of the writers on Sclerotium rolfsii have mentioned an attempt 

 to carry out pure culture inoculations to prove the pathogenicity of the 

 fungus. It seems to have been taken for granted that this fungus is a 



