Hi 
Research Bulletin No. 1 
TECHNIQUE. 
In their studies Appel and Wollenweber tested all sorts of 
media and came to the conclusion that the normal conditions 
for Fusarium culture could be realized on sterilized vegetable 
substrata. They used as much as possible the tissues of the host 
on which the fungus is found. 
In the course of these studies with Fusarium tuberivorum, 
sterilized potato plugs, sterilized potato stems, raw potato 
plates, glucose agar, beef bouillon (4-10), sawdust soaked with 
potato- vine extract, filter paper soaked with a synthetic solution 
of the same composition as the glucose agar, and potato agar 
were used as solid culture media. Various liquid media, such as 
glucose solution and water, were used. 
The plugs were prepared from potato tubers grown under 
irrigation and put into Roux tubes whose container was half 
filled with water. The tubes were then plugged and sterilized by 
steaming on three consecutive days at 100° C. The first day they 
were steamed for a period of one-half hour and on the other days 
for a period of 15 minutes. Pieces of young potato vines were 
prepared in the same manner. 
The glucose agar used was of the same composition as that 
used by Appel and Wollenweber with the exception that 15 grams 
of agar were used instead of 10 grams. 
The following is the formula for the agar: 
1,000 c.c. water. 
20 grams ammonium nitrate. 
10 grams di-potassium phosphate. 
5 grams magnesium sulfate. 
100 grams glucose. 
15 grams agar (Witte's powdered). 
The chemicals were Merck's and chemically pure. The agar 
was dissolved in the water, autoclaved and then the other in- 
gredients were added and the solution sterilized on three con 
secutive days at 100 C. in streaming steam. 
Cultures were also grown in hanging drops of agar prepared 
in the above manner and in distilled water. By using these drops 
we were enabled to study the progress of a single spore's develop- 
ment for nine days. Some cultures were also grown in Erlen- 
meyer flasks in distilled water, 1 per cent glucose, and in a solu- 
tion of the following composition : 
1.000 c.c. water. 
20 grams ammonium nitrate. 
10 grams di-potassium phosphate. 
5 grams magnesium sulfate. 
100 grams glueose. 
