CEREALS 



341 



plants, and it has been proved experimentally that such 

 seed carries the disease 

 to the offspring.^ 



As a preventive meas- 

 ure resistant varieties 

 should be selected for 

 planting, and all seed 

 from plants which are 

 at all diseased should be 

 avoided. The disease 

 may be carried from one 

 locality to another Ijy 

 any of the means sug- 

 gested under soil dis- 

 eases, and especially by 

 manure infected with 

 stalks of diseased plants. 



Rust (Puccinia Sorghi 

 Schw.). — Corn rust 

 seems to have taken its 

 place in literature in 

 1815. It is of compara- 

 tively slight harm, since 

 it does not usually 

 develop early in the 

 season, though in ex- 

 ceptionally favorable 

 climatic conditions it 

 may develop early upon 

 young plants. Its injury is then greater. 



1 Smith, E. F., Sci. n. s. 30, 223 



Portion of corn leaf showing sori of 

 rust. Original. 



The loss is en- 



