164 EXPERIMENT STATION. [Jan. 



NOTES ON THE OCCURRENCE OF FUNGOUS 

 SPORES ON ONION SEED. 



BY GEORGE H. CHAPMAN. 



It has been found in the seed separation and germination work 

 in this dei^artment that spores of various fungi are often found 

 on market seeds. This has been especially noticed in the germi- 

 nation work, for in many cases, no matter how carefully the 

 germinating dishes were sterilized and the tests carried on, some 

 of the samples would mold much worse than others. It was also 

 thought that in the case of onion seed the spores of onion smut 

 might be carried from one locality to another, and thus spread 

 the disease in that way. 



Under the direction of the head of this department several 

 samples of onion seed were examined during the past year and 

 the different kinds of spores present noted. The method of ex- 

 amination was as follows : — 



A representative sample of the lot was taken, and then of 

 this sample about 15 grams were shaken up with warm, dis- 

 tilled water for ten minutes. The supernatant liquid was then 

 drawn off in a pipette and drops placed on a slide for examina- 

 tion. Several examinations of each sample were made and the 

 different kinds of spores found were noted. This method of de- 

 taching the spores may be open to objections, but it is thought 

 that enough of the spores are detached to give an idea of the 

 different kinds present. 



In all, ten different samples of seed were examined, and in two, 

 onion smut spores were found in small quantity. It has been 

 the generally accepted opinion that the smut spores do not occur 

 on the seed, but this idea is probably due to the fact that only 

 in very few cases do these spores appear to be present. From 

 our results we are forced to conclude that onion smut spores may 



