14 



THE SUSCEPTIBILILTY OF CERTAIN CEREALS TO SMUT. 

 Leonard S. Kiinck, Macdonald College. 



That certain varieties of cereals are inore susceptible to the attacks of 

 smut than others is a matter of common knowledge. This fact should be 

 borne in mind b}' every breeder of small grains when making his selections 

 for foundation stocks. Much valuable time has been lost and much money 

 needlessly spent in attempting to breed strains resistent to certain diseases 

 when varieties; nearly immune naturally, already existed. 



In order, therefore, to secure information as to the degree of smut 

 resistance naturally possessed by the different varieties of cereals under 

 test at the College, no grain sown on the plots has been treated for smut 

 for the past four years. After a lapse of two years, in order to allow the 

 influence of former treatments to be largely overcome, we began making a 

 count of the actual number of heads smutted appearing in each varietj^ The 

 heads were gathered three times a week during the period when the smut 

 was in evidence and a record made of the number found on each plot. Since 

 the results obtained cover a period of but one year in some cases, and but 

 two years in other cases, the conclusions drawn should be regarded as ten- 

 tative and suggestive rather than conclusive. 



A study of results obtained would indicate that the following factors 

 play an important part in determining the amount of smut : — 



First — Season. 



Second — Class of Grain. Milling spring wheats are more susceptible 

 than durum wheats. Two-rowed Duckbill barlej^s are less resistant than 

 two-rowed Chevalier barleys. The Chevalier, in turn, is much more suscept- 

 ible than the average six-rowed class while the hulless varieties appear prac- 

 tically immune. 



Third — Variety. In the milling spring wheats, Pringle's Champion 

 gave 1 smutted head; Huron, 293. In the durum wheats, Medeah gave 1 

 smutted head; Eoumanian, 147. In the six-rowed barleys, Oderbrucker gave 

 1 smutted head ; California Brewing, 341. Two-rowed Duckbill gave 

 .as high as 364 smutted heads; two-rowed Chevalier as high as 50. Of four 

 varieties of hulless barleys tested three did not produce a smutted head 

 while the fourth produced but one. 



Fourth — Strain. Of three strains of Red Fife wheat, obtained from 

 widely-removed sources, the most resistent produced 24, the second 108 

 and the third 278 smutted heads respectively. 



