448 



IOWA DEPARTMENT OF AGRICULTURE 



The amounts of these solutions used per bushel ranged from one to 

 eight pints or one gallon. Different lots of seeds were treated with the 

 different solutions and covered for different periods of time ranging from 

 to fourteen hours. Germination tests were made with each lot of seed 

 treated to determine the effect of treatment on the vitality, and plots 

 were seeded in the field to determine the direct effect of the formalde- 

 hyde in killing the sxQut, as well as to determine the yield of the treated 

 seed compared with the same seed untreated. With slight variations 

 these tests were repeated in 1916 and in 1917. 



TABLE I— SHOWING YIELD IN BUSHELS PER ACRE OF DIFFERENT 



LOTS Of seed oats treated WITH VARIOUS AMOUNTS OF 



FORMALDEHYDE. 



TABLE II — SHOWING YIELD IN BUSHELS PER ACRE OF SEED OATS 



TREATED WITH FORMALDEHYDE AND THEN COVERED FOR 



A^VRIOUS PERIODS OF TIME. 



All of the treatments were effective in killing the smut in 1915 tho 

 the untreated seed showed but slight infection: 1.83 per cent of smut. 

 In 1916 the untreated seed produced 12.7 per cent smutted plants. The 

 use of one to fjve solution, (one pint of formaldehyde and five gallons of 

 water), also the one to ten and one to twenty solutions, entirely killed the 

 smut as did seven of the treatments with the one to thirty solution. All 

 of the plots treated with the one to forty solution showed a few heads of 

 smut, but in no case did the number approximate one per cent. 



