FORMALIN TREATMENT FOR OAT SMUT 617 



Effects of Various Treatments upon the Smut. 



In the field tests the grain was seeded on April 10th and 

 11th. Headin- was completed between the dates of June 22d 

 and 26th, and the grain was all ripe July 16th to 18th. Har- 

 vest was finished by July 20th. Notes on the percentage of 

 smut were taken at full heading. A two-foot division board 

 was used for spacing the plants while counting. Six counts 

 were made on each plot. The division stick was inserted at 

 given intervals on a number of check plots. In this manner 

 thirty-one checks were counted and the resulting average used 

 for the compilations. There was an average of 105 panicle- 

 bearing stems in the two-foot space. Only an average of 1.83 

 per cent of smut was noted on the checks, some ranging higher 

 than others. This percentage was much below the expected, 

 yet it served, to indicate the value of the treatments. 



In counting the percentage of smut on the treated plots every 

 row was observed. In no instance did the formalin treated plots 

 show any smut. This was contrary to expectations, especially 

 in the case of one to forty solution when applied in small 

 amounts. Such results can hardly be accounted for since there 

 was not a check that was not infected. 



The plots treated with hydrogen peroxide showed as much 

 smut as the cheek plots. It is no doubt safe to say that such 

 peroxide treatments as were used can not be relied upon to 

 control the oat smut. 



It has been recognized for some time that, climatic- conditions 

 have more or less influence on the intensity of the oat smut 

 disease. When the seeding period is followed by warm weather 

 a greater percentage of smut has been observed under similar 

 conditions than when followed by cool weather. This is due in 

 part to the maximum temperature of the smut spore being com- 

 paratively high. This, together with the adaptability of the 

 oat plant to a cool moist climate, may account for the compara- 

 tively small percentage of smut in the test plots. The reverse 

 conditions would result with wheat owing to the fact that wheat 

 does best in a warm seed bed. 



While some satisfactory results have been secured in regard 

 to various formalin solutions and their methods of application 

 it is desirable that the experiments be conducted one or more 



