944 



EXPERIMENT STATION RECORD. 



"When considered in proportion to the whole amount of nitrogen compounds 

 present, there is a large increase in the gliadin from the earliest cutting of the grain 

 until it is ripened. There is a marked but smaller decrease in the proportion of 

 gluteniu over the same time and a very rapid falling off in the proportion of amids 

 during the first few days. The changes in the proportion of edestin and leucosin 

 during the entire time of cutting is less marked and more irregular. 



"There is a corresponding but less marked change in these same compounds when 

 ^considered in percentages of the dry matter of the grain. 



•'The nitrogen compounds in this grain when ripe were in about the following 

 proportions: Amids 1, edestin and leucosin 3.5, gluteuin 10, and gliadin 16. 



"There was over the period preceding ripening a very appreciable larger percent- 

 age of nitrogen in the wheat of heads cut from the straw at the time of the gather- 

 ing than in that gathered at the same time and dried on the straw, the explanation 

 of which seems to be that the transfer of dry matter from the straw to the grain 

 after cutting was largely one of non-nitrogenous matter. 



"When considered in relation to the whole amount of nitrogen compounds present, 

 there was little difference in the proportions of the different nitrogen compounds in 

 the wheat dried on the straw and in that of heads cut from the straw." 



To study the changes iu the nitrogenous cornpouuds in the endosperm, 

 samples of the wheat from the sixteenth to the thirtieth cuttings were 

 milled in a small roller Hour mill provided for the purpose, and the 

 nitrogenous compounds iu the hour determined. The results are tabu- 

 lated on the basis of the total dry matter aud of the total nitrogen, and 

 are compared with those obtained for the whole wheat. These showed 

 that the difference between the total nitrogen iu the whole wheat and 

 in the endosperm was very appreciably greater in the ripe wheat than 

 in the wheat cut a week or 10 days earlier. Up to about 2 weeks before 

 ripening the gliadin nitrogen formed a greater proportion of the dry 

 matter of the endosperm than of the whole wheat, but from that time 

 until ripening this was reversed, the proportion of gliadin nitrogen 

 being greater in the whole wheat than in the endosperm. 



A study was also made of the proximate composition of wheat at dif- 

 ferent stages. The samples cut at different stages and dried on the straw 

 were analyzed and the results in periods of 3 days, corresponding to the 

 stages of ripeness mentioned in the preceding table, are given as follows : 



Proximate composition of wheat at different stages, calculated to dry matter. 



Period. 



1 



2 

 3 



4 

 5 

 6 



7 

 8 

 9 

 111 

 11 

 12 

 13 

 II 



Ash. 



Per ct. 

 4.81 

 4.16 

 3.24 

 2.52 

 2.16 

 2.07 

 1.82 

 1.80 

 1.68 

 1.79 

 1.77 

 1.59 

 1.87 

 1.69 



Pro- 

 teids. 



Per ct. 

 17.80 

 17.30 

 15.36 

 14.30 

 13.75 

 13.15 

 13.64 

 14.55 

 15.40 

 16.24 

 14.96 

 16.59 

 16.56 

 17.26 



Amids. 



Per ct. 

 2.83 

 1.40 

 1.01 

 .91 

 .78 

 .56 

 .51 

 .50 

 .44 

 .50 

 .44 

 .61 

 .62 

 .56 



Fats. 



Per ct. 

 4.32 

 3.09 

 2.64 

 2.51 

 2.31 

 2.38 

 2.45 

 2.59 

 2.60 

 2.44 

 2.50 

 2.37 

 2.46 

 2.52 



Crude 

 fiber. 



Per ct. 

 8.69 

 6 96 

 5.50 

 4 56 

 3.72 

 3 30 

 3.10 

 3.11 

 3.01 

 3.03 

 3.04 

 2.98 

 3.00 

 2.96 



Pento- 

 sans. 



Per ct. 

 13.54 

 12.84 

 12.28 

 11.10 

 9.73 

 9.66 

 9.32 

 8.82 

 8.50 

 8.41 

 8.08 

 8.16 

 8.33 

 8.63 



Dex- 



trins. 



Per ct. 

 2.00 

 3.07 

 2. 86 

 2.66 

 2.26 

 2.11 

 1.94 

 1.75 

 1.72 

 1.83 

 2.46 

 1.77 

 1.79 

 1.75 



Starch 

 and un- 

 deter- 

 mined. 



Per ct. 

 41.51 

 47. 74 

 54.68 

 59 42 

 63. HO 

 65. 27 

 65. 72 

 Of,. 45 

 65. 36 

 64.32 

 65. 23 

 64.42 

 6S.84 

 63. 15 



