102 PROTECTION OF PLANTS — '1922-23 



EXPERIMENTS IN THE CONTROL OF OAT SMUT. 

 B. T. Dickson, R. Summerby, and J. G. Coulson. 



The chief grain crop in the province of Quebec is oats, and consequently 

 the control of oat smuts is of the utmost importance. The ideal method would 

 be to use absolutely clean seed, but since this is not commnoly possible at 

 present, it is necessary to disinfect the available grain by some means. The 

 usual methods of doing this are thoste involving the use of formaldehyde 

 either in a concentrated form i. e. equal parts of commercial formalin and water 

 sprayed thoroughly (so-called "Dry Method") or by soaking in, or thoroughly 

 sprinkling with, formalin 1 pint in 320 pints of water. The latter metliod is 

 safe and gives excellent control, but since it requires considerable time, the 

 handling of quantities of water and formalin, and since it cauges swelling of 

 the grain, etc. many farmers do not practise disinfection. If therefore a 

 simpler method can be used it may become more popular. 



In this connection considerable work has been done in Australia with 

 stinking smut or bunt of wheat. In 1917 Darnell-Smith (Agr. Gaz. New 

 South Wales 28: 185-189, 1917) reported good control by the use o^ copper 

 carbonate dust and again in 1919 Darnell-Smith and Ross (Agr. Gaz. New 

 S^^uth Wales 32: 685-692, 1919) reported good results. The trials were repeated 

 on this continent in California by Mackie and Briggs in 1920 (Science N. S. 52: 

 540-541, 1920) and again in 1921 (Phytopath. 11: 38-39, 1921). In 1921 

 Lambert and Bailey (Phytopath. 12: 36, 1922) confirmed the work of previous 

 investigators and further showed the use of copper carbonate dust in con- 

 trolling oat smuts. 



As a result of this and other work not mentioned here it was decided that 

 a project testing the use of copper carbonate among other disinfectants was 

 worth while and the Crop Protectibn Institute appointed a committee to organ- 

 ize such a project. Among representative American and Canadian Institutions, 

 Macdonald College was asked to co-operate through the first named author 

 of this paper. Land, seed and labour were provided through the courtesy 

 and co-operation of Prof. R. Summerby of the Agronomy Dept. and Mr. J. G. 

 Coulson, M. A., made soil moisture tests and careful percentage counts during 

 the season. All three authors co-operated in the planning and treatment. 



Grain used. 



Banner and Hull-less No. 709 MC oats of good average quality were used 

 in the tests. The lots of grain were thoroughly shaken with viable spores of 

 loose smut so that each grain carried a heavy spore load. That this is the case 



