SEED DISINFECTION FOR PURE CULTURE WORK 



H. C. YOUNG 



Forme 



Washington University 



In recent years the growing of seed plants in pure cultures 

 for both physiological and pathological purposes has become 

 recognized as an important research method. When parasitic 

 fungi are being studied in relation to their hosts it is necessary 

 to control as many conditions as possible, and especially is it 

 essential to prevent the entrance of other parasites. More- 

 over, when the relations of higher plants to organic nutrient 

 solutions are being investigated, it is usually necessary to elim- 

 inate the possible action of all microorganisms. In order to 

 obtain plants free from bacteria and fungi many and varied 

 methods have been advocated. It is obviously necessary to 

 begin with pure seed or with disinfected seed. This paper 

 deals only with the latter possibility in the establishment of 



pure cultures. 



An examination of the literature indicates that many germi- 

 cides have been tried in an effort to disinfect seed. In most 

 cases, the investigator has selected some particular germicide, 

 which had proved favorable in one or more cases, and has at- 

 tempted to make it applicable to all seeds under all conditions. 

 Accordingly, when others attempt to use the method under 

 different conditions poor results are obtained and the method 

 may be considered a failure. There is much dissatisfaction, 

 therefore, with any single germicide as an agent which will 

 disinfect all seed under all conditions. 



The chief observation that suggested a further test of dis- 



infectants was the difficulty experienced, at the Missouri 

 Botanical Garden, in obtaining consistent results in regard to 

 seedlings relatively free from contamination for certain "im- 

 munity" experiments in which the author was associated with 

 Dr. Duggar. It was found that seeds of the same varieties 

 grown in different parts of the country had to be treated dif- 



Ann. Mo. Bot. Gard., Vol. 6, 1919 



(147) 



