446 



SCIENCE 



[N. S. Vol. LII. No. 1349 



stimulating tone and its frank acknowledg- 

 ment of our ignorance in regard to many 

 matters of fundamental importance. So 

 valuable a work should have been printed on 

 much better paper, but the exigencies of the 

 war probably made this impossible. One 

 could have wished also that the author had 

 provided the volume with an index and had 

 seen iit to give careful citations of the many 

 interesting works to which he refers. 



W. M. Wheeler 



SPECIAL ARTICLES 



ON THE PROTEIN CONTENT OF WHEAT 



Wheats of the Pacific coast states are con- 

 spicuously low in protein, so much so that 

 western millers are obliged to ship in large 

 quantities of high protein wheat to mis with 

 their domestic wheats in order to manufacture 

 flour of good baking qualities. The cause of 

 the low protein content of western wheats 

 has been the object of considerable investiga- 

 tion on the part of interested agronomists 

 and plant physiologists for the last two 

 decades. Eesults obtained from these investi- 

 gations have led to a rather common belief, 

 that the cause of the low protein content of 

 Pacific coast wheat is primarily attributable 

 to peculiar influences of climate. 



In an investigation by the writer on the 

 effect of applications of certain forms of 

 soluble nitrogen to plants at different growth 

 phases, results obtained with wheat, one of 

 the plants studied, throw new light upon this 

 protein question. In this paper, only that 

 part of the plan and the results that pertain 

 to the subject under discussion, need be given. 

 These are essentially as follows : 



Glazed stone jars were filled with a soil 

 very low in nitrogen. This soil, as taken 

 from the field, had a very low crop-producing 

 power when cereals were planted, but upon 

 receiving a moderate application of soluble 

 nitrogen salt would yield large crops. This 

 soil was planted to a pure strain of White 

 Australian Wheat. Two hundred and fifty 

 milligrams of nitrogen per jar, that is, at the 

 rate of 100 pounds of nitrogen per acre, were 

 added in single applications to different jars. 



at dfferent times' during the growng period of 

 the plants. The nitrogen was added in two 

 forms, ISTalSrOg and (]SrH^)2S04, respectively, 

 for two different series that were tested. 

 Every application was made in triplicate. 

 The first application of nitrogen to the first 

 set of triplicates of each of the two series 

 was made at the time of planting, the second 

 was made to other jars 17 days after planting 

 and so on at intervals until the last sets in 

 each of the JSTalSTOg and (NH^)2S0^ series 

 received their nitrogen application 110 days 

 after planting. Every application of nitrogen 

 made to the several sets in the series was, 

 therefore, made at different ages of the plants 

 and obviously represents more or less different 

 growth phases of the plants. The tabulated 

 data for a N'aN'Og series will serve as an 

 example of the plan of the investigation and 

 gives the results obtained. 



EFFECT OP NaNOa APPLICATIONS ON THE PROTEIN 

 CONTENT OP SPRING WHEAT APPLIED AT DIF- 

 FERENT GROWTH PHASES OF THE PLANTS 



Eesults Average of Triplicate Jars 



It will be noted that the data show a 

 decided increase (about YY percent.) in the 

 protein content of wheat obtained from the 

 plants that received nitrogen when they were 

 110 days old over those that were treated with 

 nitrate at the time of planting. The protein 

 content of the wheat obtained from these two 

 different treatments are respectively 15.2 per 

 cent., and 8.6 per cent. The data show that 

 for each of the different applications of 

 nitrate made after the time of planting, there 

 was a corresponding increase in the protein 

 content of wheat. As these increases in the 



