SECTION XI 



SPECIAL METHODS 



For a detailed discussion of sterilization see one of the 

 standard works on bacteriologic technic. Here only special 

 phases of this subject will be considered. 



Seed Sterilization. — ^Although a great number of methods 

 employing various agents have been recommended for 

 removing micro-organisms from seed, only a few of the 

 more promising ones will be given. Where it is not neces- 

 sary to render the seeds free of bacteria, but merely to 

 destroy the majority of the flora, alcohol may be used. 





Fig. II. — Apparatus for seed sterilization. 



Among the chemicals that have proved satisfactory for 

 sterilizing seed, mercuric chlorid, hypochlorate of lime, and 

 silver nitrate are the most commonly used. The effective- 

 ness of these substances depends on many factors: strength 

 of solution, time of exposure, temperature, pressure, and 

 nature of the seed coat. 



