38 



Robert S. Kirby 



TABLE 5. Relation of Date of Sowing to Amount of Disease 



Rate of seeding 



In Europe, where take-all is not sharply defined from several other 

 foot rots, Guerrapain and Demolon (1913), Mangin (1914), and Foex 

 (1919 b) all state that increasing the rate of seeding is favorable to the 

 disease. In order to determine this point, test rows of winter wheat were 

 planted in the 1921 plot at Ithaca and inoculated with pure cultures. The 

 results, given in table 6 show that the percentage of badly dwarfed plants 

 increases with the heavier seeding of the land. 



TABLE 6. Effect of Rate of Seeding on the Disease 



Elate of seeding per rod-row 



Per cent of take-all-infected plants 



Plants less 



than 



\ normal 



height 



Plants 



2 uu 10 



normal 

 height 



Plants 



of 

 normal 

 height 



Per cent 



of plants 



not infected 



Light, 7h grams. . 

 Normal, 15 grams 

 Heavy, 30 grams . 



23.2 

 30.0 

 38.0 



30.3 

 33.5 

 34 



46.5 

 33.5 

 28.0 



0.0 

 3.0 

 0.0 



CONTROL 

 EXCLUSION 



A quarantine to prohibit the importation of possible harborers of the 

 pathogene was attempted in the United States in 1919 (Ausley, 1919). 

 Present evidence, such as the general distribution of take-all in the State 



