200 Proceedings of Indiana Academy of Science. 



Early blight caused by AUemaria solani was found epidemic in a field ol 

 early potatoes near Indianapolis July 17, and the disease was also noted at 

 Lafayette in the late crop. In October Gregory and Gaylord found early 

 blight prevalent in Floyd and Clark counties in the extreme southern end 

 of the state. 



Pig. 8. Potato scab. 



Common seal) (Fig. S) was of general occurrence where imtreated seed 

 was used and soil infestation is not uncommon since scab occurred in 

 some fields planted with treated seed. As a result of the observations of 

 Gaylord and Gregory scab is known to have been present in Lake, Porter, 

 Laporte, St. Joseph, Lagrange. Dekalb, Fulton, Cass, Whitley, Carroll, 

 Tippecanoe, Clinton, Madison, Hancock, Marion, Clark and Floyd counties. 



Black scurf caused by Rhizoctonia solani was of widespread occurrence 

 as a blemish of the tubers. The disease also caused the stunting and death 

 of young plants. Gaylord and Gregory report black scurf from Lake, 

 Porter, St. Joseph. Elkhart, Lagrange, Fulton, Tippecanoe, Madison and 

 Clark counties. In seed disinfection tests in Lake county as high as 67 

 per cent of the tubers in the check rows showed black scurf. The occur- 

 rence of a small percentage of black scurf on the tubers from disease-free 

 and treated seed indicated that the soil of this field which had not been in 

 potatoes for five years was infested to some extent. 



Gregory reports cases of black-leg caused by BaGillus phytophthorus in 

 Laporte, Tippecanoe and Hancock counties. 



Gregory found the non-parasitic leaf roll disease in St. Joseph, Noble. 

 Fulton. Hancock, Clark, Floyd and Dekalb counties and reports it rather 

 serious in fields noted in the latter three counties. In one field in Dekalb 

 county he reports a 50 per cent incidence of the disease and a 25 per 

 cent reduction in yield. When potatoes grown in the Wanatah region were 

 planted in the greenhouse a low percentage of typical leaf roll plants 

 resulted. 



Three typical and extreme cases of the mosaic disease occurrd in an 



