:io May, 1 910.] 



W lie at I inprovement Committee. 



treatments of the seed both before and after infection. There were ten 

 small plots altogether, each sown with 25 grains of Federation wheat 

 on 30th June, 1909, and three of these were used as a check to compare 

 with the others. Both spores and diseased straw were used for purposes 

 of infection. The following table gives the relative results : — 



Wlien seed dusted with spores was sown in clean ground, there was 

 83 per cent, of infection, and when clean seed was sown \n g.round con- 

 taining diseased straw, there was 52 per cent, of infection. The addition 

 of diseased straw to grain already dusted with spores did not increase the 

 virulence of infection. 



As regards different treatments, when the seed was dusted with spores 

 and afterwards treated with bluestone solution, the resulting plants were 

 all clean, and when the grain was treated with bluestone before the 

 addition of the spores no infection occurred. If, however, the grain was 

 treated with bluestone and diseased straw added there was infection to 

 the extent of 29 per cent. Even when the grain was treated with corrosive 

 sublimate and diseased straw added there was 44 per cent, of infection. 

 This infection could easily be accounted for, from the young shoots being 

 attacked which had necessarily no protective coating of the fungicide. 



Thus, the general results already obtained are corroborated, that if 

 the spores are only on the grain and no Flag Smut in the soil, treatment 

 with bluestone solution is a preventive. But if the diseased straw is 

 .already in the soil from a previousi crop, neither treatment of the seed 

 with bluestone nor corrosive sublimate is effective. 



Experiments will be continued this season in connection with rust and smut. 

 The different cultivated species and sub-species of Triticum will be 

 thoroughly tested, as well as the seed of various crosses supplied by Mr. 

 Biffen, of the Agricultural Department, Cambridge, who has succeeded 

 in breeding wheats immune to the Yellow Rust {Puccima glumarum) but 

 not to the Black Rust {Puccima graminis) whidh is the special scourge of 

 our wheat-fields. 



