22G Report of the Department of Botabty of the 



Exposed for 24 hours: Standard charge. 



5 lbs. per cu. ft. 

 « 



23 to 36 tubers. 



1, 



2 



3 



4 



5 



6 



8 

 10 

 12 

 14 

 16 



23 tubers. 



Exposed for 24 hours, but double quantity of chemicals. 



4 lbs. per cu. ft 1 20 5 15 



3.7 lbs. per cu. ft., dry 1 40 22.5 



3. 7 lbs. per cu. ft., wet 1 50 2 



25 



100 

 20 



DISCUSSION OF RESULTS. 



The data given in Table I and summarized in Table II, show that 

 the formaldehyde gas treatment is not reliable; that is, it is not 

 efficient in killing Rhizoctonia and some other fungi and bacteria 

 which occur on the surface of the seed potatoes. Humidity and 

 temperature do not appear to be responsible for the irregularities 

 in the efficiency of the treatment. Where several experiments were 

 conducted with equal quantities of tubers, the average results of 

 such experiments show that there is a lesser degree of efficiency 

 when there is a large quantity of tubers in the fumigator. However,, 



