378 PROCEEDINGS OF THE INDIANA ACADEMY OF SCIENCE. 



The Effect of Hydrogen Peroxide in Preventing 

 THE Smut of Wheat and Oats. 



F. J. PlPAL. 



In order to determine the effieieney of hydrogen peroxide in preventing 

 the stinking smut of wheat and the loose smut of oats, a series of field tests 

 were made on Purdue Farm, during the seasons of 1913-1914 and 1914-1915. 



Nineteen lots of winter seed wheat (Egyptian Red) and nineteen of seed 

 oats (Great Dakota), used in these tests, were mixed with spores of Tilletia 

 foetans and Ustilago Avenae, respectively, to insure abundant infections. 

 They were loosely wrapped in cheese cloth packets and soaked in the variously 

 proportioned solutions of hydrogen peroxide as shown in the accompanying 

 tables. In addition to the above samples two lots of wheat and two of oats 

 were treated with formaldehyde solution, to compare the effect of the latter 

 with that of hydrogen peroxide. Two checks were left in the wheat and one 

 in the oat tests. 



All treated samples were dried, at least partially, immediately after 

 soaking, and then sown in the field. The amount of treated grain Avas suffi- 

 cient, in each case, to seed about 300 square feet of ground. When the grain 

 headed out, careful counts were mad(> to determine the per cent, of smut on 

 each plat. 



The results of the first season's treatment, recorded in table 1, indicate 

 that the weaker solutions of hydrogen peroxide increase the infection of the 

 stinking smut of wheat to a considerable extent. In all cases, exf^ept two, 

 where the treating solution ranged in the ])roportion of hydrogen peroxide 

 to water from 1 to 100 to 1 to 25, the i)er cent, of smut was higher than the 

 average of the two check plats. The average per cent, of smut of the first 

 twelve treated plats was 18.5, as compared with 16.0 per cent, of the untreated 

 plats. The stronger solutions and pure hydrogen ])eroxide effected a con- 

 siderable decrease in the amount of smut but in no case was it eliminated 

 entirely. 



Further tests, made in the season of 1914-1915, in which the time of 

 soaking was prolonged to five hours, similar negative results were obtained. 

 The plats on which seed wheat was treated with 1 to 100, 1 to 75, 1 to 50, 

 and 1 to 25 hydrogen peroxide solutions produced 14.6 per cent, of smutted 

 heads, as compared with 12.1 per cent, on the check plat. No stronger 

 solutions were used in these tests than those indicated above. The object 

 of these trials was to use solutions of such proportions as could be employed 

 Avithin reasonable cost limits, in actual farm practice, in case they proved 

 effective against the smut disease. 



