lo April, 1909.] Rust a)ul Sniiit Ilcsistancc. 25; 



maintained under different conditions of soil and climate, heat and mois- 

 ture, were carefully planned. Mr. Sutton willingly supplied seed-wheat 

 of Florence and Genoa for the purpose, and a sufficient quantity of grain 

 was mixed with bunt spores to allow of its being sown in such distinct 

 districts of Victoria as Dookie Agricultural College in the 

 North, under the superintendence of the Principal, Mr. Pye; 

 at Longerenong Agricultural College in the West, under the 

 ■charge of Mr. Pridham ; and at Burnley Horticultuxal Gardens, 

 near Melbourne, in the South, under my own special supervision. 

 The seed was all dusted equally with spores of TiUetia levis, Kuehn, derived 

 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 are concerned. A bulk sample of wheat was mixed with the spores 

 as follows : — Bunt balls were taken direct from the wheat plant and then 

 broken up by rolling them in paper. The spores were next well dusted 

 and rubbed over the moistened grains, so that every grain looked as if it 

 had been dressed with soot. The grain was sent out immediately afterwards 

 for sowing. The results of the experiments have been carefuUv tabulated, 

 and while they show that Florence may have as much as 12 per cent, 

 of stinking smut and Genoa 22 per cent., yet on the whole they are fairlv 

 resistant. 



Burnley. — The plots were sown on i6th June in a moist seed-bed. In 

 all cases, the ordinary seed was sown as a check and the check-plots were 

 invariably free from bunt. Florence had an average of 5.66 per cent., 

 and Genoa of 4.72 per cent, of stinking smut. 



Dookie. — The sowing took place on 17th June, and the seed-bed was 

 a moist one. The average here was low, being 2.42 per cent, for Florence, 

 and 2 per cent, for Genoa. 



Longerenong. — The seed was sown on ist June in a moist seed-bed. 

 There were only two plots of each sown, a large and a small one, together 

 with the check-plots. The general average was much higher here than 

 in the other two localities, being 9.20 per cent, for Florence, and 14.60 

 per cent, for Genoa. 



The above are the results obtained by treating a bulk sample of wheat 

 v.ith spores from the same species of smut {T . levis) which is the one 

 u.sually met with in Victoria. The average varied from 2 per cent, to 

 14 per cent., and it is very noticeable the high average obtained at 

 Longerenong. 



Since the weather conditions exercise an important influence on the 

 germination of the spores, it may be noted generally for the first quarter 

 of the year 1908, that the rainfall was scarcely 50 per cent, of the average 

 amount, and this was followed bv one of the driest April months ever 

 known. The breaking up of the drought occurred in May, and the rains 

 in June were abo\'e the average, so that altogether the conditions were 

 favorable for the germination of the spores and the seed-wheat at the same 

 time. It is not always easy to account for differences in the amount of 

 infection, but if we take into account the rainfall for Mav, the month 

 preceding the sowing of the infected wheat, it may throw some light on it. 

 At Burnley it was .87 inches, at Dookie 1.99 inches, and at Longerenong 

 3.22 inches, while the mean temperature was verv much the same in all. 

 The heavy rainfall at Longerenong immediatelv preceding the sowing of 

 the wheat on ist June, would have a tendency to cause a general germina- 

 tion of the spores, and the wheat being in the best possible condition for 

 infection, there was likely to be the maximum of infection. 

 2843. I 



