SELECTION TO INrREA.SE PROTEIDS IN KERNEL. 



83 



Table 18. — Variafion-^i iti content of proteids — Contimicd. 



It will he noticed that there is a very large range of variation in 

 the proteid nitrogen content of these wheats, running from 1.12 to 

 4.95 per cent. By referring to Table 8, it will be seen that an equally 

 large variation occurred between the plants when the whole plant 

 was sampled. In the 351 anah'ses the nitrogen ranges from 1.20 to 

 5.85 per cent. This is due in the main to the ability of the plant 

 to gather nitrogen from the soil. In no one of the experiments to 

 ascertain the effect of nitrogenous manures on the composition of 

 wheat has there been an increase of more than a few tenths of 1 per 

 cent, even when the nitrogenous fertilizer was added to an exhausted 

 soil. It is, therefore, not lils;ely that such large variation in nitrogen 

 content could be due to irregularities in the supply of soil nitrogen. 

 If this ability of the plant to store up a large amount of nitrogen in 

 the kernel is hereditar}^, as results given later indicate, there is ample 

 onportunity to develop by selection a strain of wheat of high nitrogen 

 content. 



