1046 
Journal of Agricultural Research 
Vol. XXIV, No, 12“ 
The fact ^at the movement into the grain is continuous while respira- 
tion activities are in operation makes it impossible to determine the 
exact effect of respiration upon the variation in protein percentage. 
Assuming that the possible variation in protein is as great as mentioned 
above, namely, 1.46 per cent in wheat, 1.62 per cent in oats, and 2.20 
per cent in barley, this would not be sufficient to account for the wide 
variation in the percentage as found in grain when produced in different 
localities, as given in Table II. 
Upon analysis of Table II, a very wide variation in protein per¬ 
centage is found for the grains grown in different localities and also 
for different years when grown in the same locality. In the year 1921 
wheat grown in the hard spring wheat section at Fargo, N. Dak., yielded 
16.10 per cent protein, while the same variety at Puyallup, Wash., shows 
9.98 per cent. Another extreme variation may be seen by examination 
of the results at Havre, Mont., showing a protein content of 18.24 cent, 
and Waterville, Wash., 9.19 per cent in the year 1920. In the former 
case there is a variation of 6.12 per cent in this regard, and 9.05 per cent 
in the latter. It would not be possible to attribute these differences to 
the respiratory process alone, as the above results show a 1.46 per cent 
variation in the protein which can be due to this phenomenon. 
The data for oats indicate a much greater uniformity in this respect 
than is found in wheat. While this uniformity is especially prondunced 
throughout the year 1920 for the different areas, there are several cases 
in 1921 which vary considerably. The oats produced at Moccasin, Mont., 
Moro, Oreg., and Umatilla, Oreg., have a protein content which will aver¬ 
age 14.12 per cent. Those grown at Waterville and Puyallup, Wash., 
and Corvallis, Oreg., average approximately 11.32 per cent. The spread 
in oats is not so great as in wheat, but this fluctuation of 2.80 per cent 
is much greater than that caused by the effect of respiration. 
While the loss of carbohydrate material from the barley grain is much 
greater than that from wheat or oats, owing probably to the higher 
moisture content, it is not sufficient to account for the protein variation 
where the grain is grown under different conditions. Barley grown at 
Fargo, N. Dak., in 1920, yields 16.06 per cent protein, while that pro¬ 
duced at Corvallis, Oreg., yields only ii.ii per cent. This is a differ¬ 
ence of 4.95 per cent, which is more than twice the difference which 
could be due to respiration. In 1920, 14.50 per cent barley was pro¬ 
duced at Havre, Mont., and Logan, Utah, yields ii.ii per cent. Here, 
again, is a spread of 3.39 per cent in the protein content, or 54 per cent 
greater than that attributed to respiration. 
In a number of the analyses of each of the grains, the differences in 
protein percentage falls within the respiration possibility. These smaller 
differences may or may not be due to respiration, depending largely 
upon the environmental conditions under which the grain is matured. 
It is quite possible that respiration is effective to a degree in shaping the 
percentage composition of the grains when grown in the areas as indicated 
in Table II, but it is also possible that respiration plays a rather unim¬ 
portant role in this regard when the synthetic process which goes forward 
throughout the period of desiccation is taken into account. 
The exact influence of respiration upon the protein percentage com¬ 
position of the grain is yet to be determined, but there is no foundation 
for the general sweeping statement that the variation in composition 
is dependent upon the respiratory process. 
