108 University of California Publications in Agricultural Sciences [Vol. 1 



Discussion. — If the proportion of protein to starch, or the per- 

 centage of nitrogen, increased inversely as the amount of sun- 

 shine the phmts received we would expect the percentage of 

 protein to be highest in the plants receiving only one quarter of 

 the total sunshine and to decrease gradually to full sunshine. 

 This, however, does not seem to be the case. Taking the 

 average of the six samples grown at the Tulare station 

 in 1908, we find just the opposite result. The protein content 



increases with the sunshine quite uniformly. The wheat from the 

 plants receiving one-half sunshine contain .47 per cent more 

 protein than the wheat from those recei^ang one-quarter sunshine. 

 The wheat receiving full sunshine contained .91 per cent more 

 than those receiving only one-half sunshine. Unfortunately the 

 samples grown under three-quarters sunshine were lost, so that 

 we are unable to say Avhether or not the protein content here 

 would have been above or below that of full sunshine. 



The analysis of the individual samples in this set show 

 that only one departs markedly from the average. In the 

 variety no. 879 we find that the wheat grown under one- 

 half sunshine had a higher protein content by .29 per cent than 

 did that grown under full sunshine, while that grown under 

 one-quarter sunshine is the lowest of the three by .17 per cent. 

 In sample no. 899 we find that one-quarter and one-half sunshine 

 gave nearly the same results, with a slight difference in favor 

 of the former. 



The general trend of the results from 1909 experiments is 

 much the same. The average of the samples grown under one- 

 quarter and one-half sunshine are about equal, while the protein 

 content of those grown under three quarters and full sunshine 

 are much higher. If we exclude sample no. 1046G grown under 

 one-half sunshine, which is unusually low, the average for 

 one-half sunshine is 12.25 per cent. This gives, then, quite 

 a gradual increase in protein content from one quarter to three 

 quarters sunshine, while the full sunshine samples average .5 

 per cent lower than those receiving only three-quarters sunshine. 



The results from the experiments at Davis are slightly more 

 erratic, but the general trend is the same as that obtained at 

 Tulare during the season of 1909. The samples under one third 

 sunshine average .24 per cent more protein than did those under 



