WHEAT CULTURE. 



333 



Whilst the mel hods recommended 

 for treating seed grain will destroy 

 the spores which have become free 

 from the bunt balls, none of them 



is EFFECTIVE FOB DESTROYING THE 



SPORES which akk CONTAINED IN 

 UNBROKEN BUNT BALLS. It IS, 

 THEREFORE, NECESSARY, IF ANY 

 TREATMENT is TO BE EFFECTUAL, 

 THAT THE UNBROKEN BUNT BALLS BE 

 EITHER REMOYED OR BROKEN BEFORE 

 THE SEED is " PICKLED." If tliis is 

 not done the hunt hulls are likely 

 t<> become broken, during the sub- 

 sequent operation of planting, and 

 their contents (a myriad living 

 spores) spread over the treated grain, 

 thus nullifying all that has been 

 done : the effect of the treatment is 

 mainly to destroy the spores adher- 

 ing to the grain ; it does not render 

 the grain absolutely immune to the 

 attacks of Smut or to other spores 

 that may become attached to it 

 after treatment. 



It has been calculated that in a 

 single hunt ball — no larger than a 

 grain of wheat — there are about 



4,000,000 



Fig. 4.— Bunt Balls. 



The "Pickle" lias no effect on the spores 

 contained in tlie unbroken balls. 



Fig. 5.— Various Stages of Germina- 

 tion of Wheat during which Infec- 

 tion by Bunt Spores may take place. 



(a) Primary rootlet, (b) stc;::, ■) 

 secondary rootlets, (d) protective 

 sheath, (e) point where first 

 green leaf pushes through the 

 sheath, after which stage no infec- 

 tion occurs. (Ottawa Bui., 73. 

 Drawings from diagrams in Ken- 

 sington Museum.) 



spores, each of which is capable 

 of causing one wheat-plant to be smutted. 

 In a bushel of wheat there are 600,000 

 to 1,000,000 grains. There are, therefore, 

 in a single bunt ball enough spores, if 

 regularly and evenly distributed, to provide 

 each grain in a bushel of wheat with from 

 four to six spores. The great necessity for 

 removing the bunt balls or breaking them so 

 that the fungicide can act upon their contents. 

 is obvious. 



Fortunately, it is easier to remove the bunt 

 balls than to ensure that all are broken. Bunt 

 balls are very light and float in water, so 

 that if the wheat to be treated is poured 

 slowly into the "pickle," and in such a way 

 that the bunt balls are not carried down by the 

 grain, the bunt halls will float on the top and 

 can be skimmed off and destroyed. As a fu. 

 ther precaution, and in order to release any 

 bunt balls which may have been carried 

 down by the grain, the grain should be 

 stirred or raked ; this is also likely to break 

 up any partially broken bunt balls which 

 have sunk and become soft. 



