1913 ] Shaw : Studies on Influences Affecting Protein Content of Wheat 67 



Variation in Individual Plants. — That there is a wide dif- 

 ference in the ability of individual plants to elaborate protein 

 in the grain is shown from the analysis of a number of varieties 

 grown under like conditions on the same character of soils. These 

 plants were all grown in the same season in centgener plats, the 

 plants being four (4) inches apart each way, and seeded at uni- 

 form depth by means of a centgener planter. The outside rows 

 were all cut away at harvest and discarded, so that none of the 

 plants shown here represent outside rows, but all had a uniform 

 feeding area on uniform land. 



In each of the lots shown in Table 1 it will be noted that there 

 is a great variation between individual plants even when grown 

 under exactly the same climatic and cultural conditions. The vari- 

 ation in individual plants of the variety White Australian ranged 

 from a minimum of 9.06 to 15.31 per cent total protein, or a 

 variation of 6.25 per cent within 25 plants, and the range in 

 Little Club is even greater, being from 7.12 to 15.22. 



Such evidence as that presented above would seem to throw 

 the main factors determining the protein content of wheats, and 

 inferentially other grains, externally, primarily upon some cli- 

 matic influence, and secondarily upon the internal factors of 

 variety and individuality of the plant itself. It seems certain 

 that the individuality of the wheat plant is just as potent in 

 determining the protein content of the grain as is the indiv- 

 iduality of the dairy cow in determining the fat content of her 

 milk and that it is just as impossible to feed protein into wheat 

 by increasing the available nitrogen of the soil as it is to feed 

 butter-fat into a cow's milk. 



Following these general considerations of some of the external 

 and internal factors bearing upon the question of protein vari- 

 ation, attention is turned to more restricted phases of the problem. 



