1919] 



T 



DUGGAR AND DAVIS — SEED DISINFECTION 



163 



the capacity for vigorous germination. Similar observations 

 upon the seed of certain grasses, sorghums, etc., which had 



undergone considerable heating 



during the 



curing process 



have led to the conviction that penetration of the seed by 

 microorganisms, especially fungi, is not infrequent, and there- 

 fore a certain "purity" of the seed employed is requisite. 



In table i are shown data obtained from the treatment of 

 Canada field peas and corn with chlorinated lime, chlorinated 

 potash, and chlorazene. In this case the first-mentioned disin- 

 fectant was more injurious to peas than in any other test made. 

 The results with chlorinated potash were considered particu- 

 larly good for the preliminary trials, while the results with 

 chlorazene were disappointing. 



Before proceeding further, tests were made, for compari- 

 son, with formalin and mercuric bichloride, and a second trial 

 of chlorazene was included, as given in table n. The use of 

 mercuric bichloride with such seed gave perfect disinfection, 

 but these, as well as subsequent experiments, seemed to indi- 

 cate that whenever this result was accomplished the injury 

 to the seed was considerable. Various grades of alcohol, from 

 20 to 95 per cent, were also used in this series, the treatment 



TABLE I 



DISINFECTION OF SEED (AFTER IMMERSION IN WATER FOR 16 HOURS) BY CHLO- 

 RINATED LIME, CHLORINATED POTASH (JAVEL WATER), AND CHLORAZENE. 



ftvat, OBSERVATIONS AFTER 72 HOURS. ROOM TEMPERATURE 



Disinfectant 





Treatment 3>h hours 



' o Germi 

 nation 



% Contami 

 nation 



Peas 



25% 



15% 



25% 



10% 

 4% 



2% 



1% 



chlor. lime 

 chlor. lime 

 chlor. potash 

 chlor. potash 

 chlorazene 

 chlorazene 

 chlorazene 



Corn 



15% 



25% 



10% 



4% 

 2% 



1% 



chlor. lime 

 chlor. lime 

 chlor. potash 

 chlor. potash 

 chlorazene 

 chlorazene 

 chlorazene 



12 

 6 



88 



94 

 

 6 



42 





 

 

 

 4 

 3-4 

 



80 

 75 

 88 

 94 

 94 

 88 

 75 







7 







3-4 







7 

 



Treatment \ hour 



% Germi- 

 nation 



25 



• • 



100 



88 







25 



87 



87 



80 



100 



100 



100 



66 



87 



% Contami 

 nation 



t • 









 

 

 

 





 7 

 3 

 

 11 

 10 

 7 



