726 



Preventing " Bunt " in Wheat. 



[Nov., 



In the first place it seemed desirable to ascertain whether 

 whole bunted grains could be passed through a drill without 

 being broken up. The following method of testing this was 

 devised : 1,000 bunted grains were counted out and mixed with 

 a gallon of seed free from bunt ; this was passed through a drill* 

 and collected. It was then steeped in water, when the bunted 

 grains floated to the top and were collected and counted : 996 

 of the original 1,000 were collected in this way. A few of these 

 were found burst in the water but this was probably due to water 

 soaking in through slight cracks, as this was found to occur when 

 slightly cracked bunted grains were put into water, but with 

 these exceptions the grains were recovered whole. There 

 appears then to be little danger of bunted grains becoming 

 broken up in passing through a drill of the type used. 



The field experiments for 1922 were modified from those of 

 previous years in order to study the effect of deliberately sowing 

 whole bunted grains with the seed. 



About 1 pint of bunted grains had been collected from the 

 plots of the previous season's experiment. 90 c.c. of these were 

 measured out into each of 5 glasses; the rest were crushed up 

 with a pestle and mortar and the powder (consisting of the spores 

 of the bunt fungus) was sprinkled over about 1J bushels of seed- 

 wheat (Standard Eed), the whole being mixed together until 

 every grain, so far as could be seen when examining a handful 

 of the seed, had a blackened tuft of hairs at the tip. 



Ten separate gallons of this inoculated seed were then mea- 

 sured out, and to each of five of these were added 90 c.c. of the 

 whole bunted grains, i.e., approximately 2 per cent. 



The samples were then treated as shown in the accompanying 

 table. The formalin, applied as in previous experiments, was 

 used at strengths varying from 1 : 820 to 1 : 800. The plots 

 were sown on the second dav after the treatment. 



The plots were examined periodically but no difference in the 

 stand could be detected among the plots. At harvest time 1,000 

 ears were collected from each plot and the number of bunted 

 ears present ascertained. 



Since, on the whole, the plots of which the seed contained 

 unbroken bunt grains showed no more bunt than those of which 



* The drill used was a Massey Harris No. 5 Disc Drill f" force feed "), set 

 to sow 3 bushels to the acre, travelling at a speed of 2 miles per hour. The 

 machine was operated, for the object of the experiment, by means of a crank 

 turned by hand, so that the machine itself was stationary, thus enabling- the 

 pasfipd seed to be collected in a sheet placed bflow the drill. We wish to 

 thank Mr. C. Davies, Head of the Engineering Department, Wye College, for 

 his assistance in this matter 



