24 



IMPROVING THE QUALITY OF WHEAT. 



unmanured. There were three plots of each. The following is a 

 tabulated statement of their results: 



It will be noticed that the effect of the nitrate fertilizer was to 

 decrease the yield of grain, but to increase the size of the kernel and 

 its content of nitrogen. 



Wolff , a as early as 1856, in summing up the experiments of Hermb- 

 stadt, Muller, and John with barley, and of Lawes and Gilbert with 

 wheat, says : 



In the presence of a sufficient amount of phosphoric acid and alkali the effect of manuring 

 with an easily soluble nitrogen compound is an improvement in the grain both in quantity 

 and quality [meaning plumper kernels]. The kernels decrease in percentage of nitrogen, 

 but become plumper, become absolutely and relatively richer in starch, and have a better 

 appearance and a higher commercial value. But when the nitrogenous food in the soil 

 exceeds a certain relation to the temperature and rainfall the quality of the grain becomes 

 poorer [harder], it becomes lighter and smaller, takes on a darker color, and generally 

 becomes richer in percentage of nitrogen in the air-dry substance. 



Von Gohren 6 also reports results of experiments in fertilizing wheat. 

 All experiments were apparently made in the same year. He grew 

 the crop on six different plots of land, five of which were manured and 

 each with a different fertilizer. In the crop he distinguished between 

 large kernels and small kernels to show the quality of the product. 

 Determinations of proteids and starch were made, and these were 

 calculated to the yield of each constituent on each plot. 



The following table shows the yield of each of the characters deter- 

 mined, and compares those raised on the unmanured plot with those 

 on the manured ones by taking the former as one and reducing the 

 others to the corresponding figure : 



The results show an increased yield from the use of fertilizers, the 

 production increasing with the application of complete manures. 



Die naturgesetzlichen Grundlagen des Ackerbauer, Leipzig, 1856, p. 774. 

 &Landw. Vers. Stat., 6 (1864), pp. 15-19. 



