Stinking Smut or Bunt in Wheat. 



77 



that he cannot account foi" the inferior protection against infection Allora 

 Spring received when treated with a stronger sohition and planted later. 



In 1902'*, the experiments were continued, but the drought which prevailed 

 and the excessive dryness of the seed bed at the time of planting were not 

 favorable for obtaining normal comparative results. Yandilla was the only 

 variety chosen, and the seed was soaked for 4 minutes in a 2| per cent, 

 solution of bluestone (1 in 40), then dried, and afterwards infected. A 

 second similar experiment was tried, the only difference being that the bluestone 

 was dissolved in water to which a little gelatine had been added to sec if a 

 thicker coating would be formed on the grain, and thus protect it all the better 

 against infection. The planting was done as late as 3rd September, and the 

 percentage of bunty plants was a little over 4 and 8 respectively. The addition 

 of gelatine did not add to the protective qualities of the bluestone solution. 



It is evident from these experiments that grain may be re-infected after 

 treatment, and every precaution should be taken to prevent this re-infection. 

 The principal source of danger arises from smut-balls, which are liable to be 

 broken in the seed drill, but no sample of wheat containing smut-balls should 

 be used for seed purposes, and any stray ones should be skimmed off in the 

 process of pickling. 



Proportion op Smutted and Sound Stalks in same Stool. 

 It is commonly stated that when a plant is infected with stinking smut 

 all the ears are generally affected, and that the cases are exceptional where 

 smutted and sound stalks occur in the same stool. But a lengthened exper- 

 ience in Australia has led me to the opposite conclusion, viz., that it is less 

 usual to find a stool in which all the ears are bunted, and it will be satisfactory 

 to give examples bearing out this contention. This occurred during the past 

 season at all the stations where bunt experiments were being conducted, but 

 actual figures will be given. At Burnley, Dexter wheat was infected with 

 bunt-spores — one plot with those of T. levis and another with those of T. tritici. 

 At the end of the season I selected ten stools with bunted ears at random from 

 each plot and counted the number of ears on each, separating them into 

 bunted and clean. The following table gives the result : — 



Table V. — Bunted and Sound Ears in each Stool of Dexter Wheat. 



It is seen from the above Table that every stool was only partially bunted 

 whether the spores of T. levis or T. tritici were used, and that in both cases 



