SMUT EXPEIUMENTS IN VICTOKIA. 591 



I. — Stinking Smut oit Bunt. 



(Tilletia tritici (Bjerk) Winl. ; and T. lev is, K^iehn.) 



This smut is known wherever wheat is cultivated, and has been, 

 recognised from the earhest times on account of the disagTeeable 

 odour emitted by it. This is due to Trimethylamin, a decomposition 

 product of the nitrogenous constituents of the parasite. There ai'e 

 two species of smuts responsible for this disease, tlie one with smooth 

 and the other with netted spores, but as both sometimes occur in the 

 same ear of wheat, and generally agree in their life history, they will 

 b^ treated here as practically the same. 



It is well known that tliis disease is caused by the sinut spores 

 adhering to the grain, infecting the young seedling, and thereby 

 enabling the mycelium of the fungus to grow inside the plant until it 

 has reached the seed-bearing stage, and then producing its spores. 



The practice of using a. " steep " for the seed, such as sulphate 

 oi copper or formalin, is also a well-known preventive of the disease, 

 since they either destroy the spores or prevent their gei-mination. 

 Seeing that the disease can be controlled, it is not regarded by the 

 intelligent farmer as of serious import ; but there is a growing feeling 

 among plant pathologists tliat all parasitic diseases, such as smuts, 

 should be combated, not merely by destroying the parasite, but by 

 rendering the host plant immune or resistant. Accordingly, the late 

 M)-. Farrer carried out the idea of producing a bunt-resistant wheat 

 plant, and it was reserved for his successor, Mr. Sutton, of the Cowra 

 Experiment Farm, New South Wales, to announce in the "Agricul- 

 tural Gazette" for March. 1908 : — " Florence and Genoa have in our 

 trial plots shown themselves under severe trial to be practically smut- 

 [iroof, and in consequence seed of them does not require to be blue- 

 stoned or treated with any other fungicide for the prevention of smut." 

 It is not necessary here to enter into any explanation of the parentage 

 of Florence and Genoa, which were selections from Mr. Farrer's 

 crosses, nor of how this supposed bunt-resistanoe was brought al>out, 

 but mei'ely to give the i-esidts of experiments designed to test how 

 far this immunity was hereditary and maintained under different 

 conditions of soil and climate, heat and moisture. Mr. Sutton 

 willingly supplied material for the purpose, and I w^as able to inoculate 

 a sufficient quantity of grain to have it sown at Dookie Agricultural 

 College, under the superintendence of the principal, Mr. Pye, at 

 Longerenong Agricultural College, under the charge of Mr. Pridham, 

 and at Bui-nley Horticultural Gardens imder my own personal super- 

 vision. 



Hulk samples of both varieties were dusted equally with spores of 

 Tilletia foetens, devrv^iX from a common source, and it is important to 

 note that the experiments were all on an equal footing, as far as the 

 amount and vitality of the bunt spores ai'e concerned. 



The seed was mixed with bunt spores as follows : — Bunt-balls 

 were taken direct from the- wheat plant, and then broken up by 

 rolling tliem in paper. The spores were next Avell dusted over the 

 moistened grains by thoroughly ruljbing them up together, so that 



