B. P. I. — 5or.. 



SEED STE.RlllZATlON AND ITS EFFECT 

 UPON SEED INOCULATION. 



INTRODUCTION. 



As a preliminary to carrying on experiments in legume inoculation 

 under control conditions, it is generally deemed advisable to disin- 

 fect the seed in order to prevent inoculation of the seedling roots 

 through wind-borne or dust-borne organisms which might be present 

 upon the seed. The subsequent effect of the sterilizing agents used 

 does not seem to have been generally considered, despite indications 

 thai ne'i-ative results secured in such tests have frequently been due 

 to traces of the chemicals adhering to the seed coat. 



STERILIZATION OF SEEDS. 



To secure some definite knowledge of the effects produced by steri- 

 lization, some experiments were started in which a number of dis- 

 infectants were used and both leguminous and nonleguminous seeds 

 were employed. Fifty seeds of each of seven different kinds were 

 treated for varying periods in test tubes, rinsed several times with 

 sterile water, and germinated in petri dishes. Equable moisture con- 

 ditions were maintained by covering the seed with sterile filter paper 

 of petri-dish size. Germination could then be noted without opening 

 the petri dishes. To determine the germicidal effect of the treat- 

 ments, platings were made on beef agar after sufficient time for ger- 

 mination had elapsed, a few seeds being shaken in with sterile water 

 or the excess water in the petri dishes being used for plating. The 

 (Termination and plating data are shown in the following tables: 



T.\i:i,i-; I. Ocniiiiinlion of .seeds (ift<r fnatniciit irHIi various disinfectants. 



[Cir. r,71 



