22 IMPROVING THE QUALITY OF WHEAT. 



Wiley" sent wheat of the same origin to Cahfornia, Kentucky, 

 Maryland, and Missouri. The original grain and the product from 

 each State were analyzed. The results of one year's test were 

 reported. Regarding the effect of climate, he says: 



There appears to be a marked relation between the content of protein matter and starch 

 and the length of the growing season. The shorter the period of growth and the cooler the 

 chmate the larger the content of protein and the smaller the content of starch, and vice 

 versa. 



Shindler,* in his book upon this subject, says (p. 75) : 



With the length of the gi-owing period, especialh' with the length of the interval between 

 bloom and ripeness, varies not only the size of the kernel, but also the relative amount of 

 carbohydrates and protein it contains. 



Again, on page 76, Shindler says: 



All this shows that the protein constituent of the kernel depends in the first place upon 

 the length of the growing period and next upon the richness of the soil. 



Melikov '" made analj^ses of different varieties of wheat of the crops 

 of the years 1885-1899 grown in southern Russia. The protein 

 varied in different years from 14 to 21,2 per cent. Melikov concludes 

 that the nitrogen content is highest in dry years and lowest in years 

 of larger rainfall, in which years the yield of wheat per acre is also 

 greater. 



Gurney and Morris,'^ in one of their reports, say: 



This increased gluten [over previous years] is probably largely due to differences in the 

 seasons, the weather being hot and dry while the grain was ripening, since it is character- 

 istic not of these wheats alone but of most of the grain grown in the colony. 



The conclusion to be inevitably derived from these observations 

 is that climate is a potent factor in determining the yield and compo- 

 sition of the wheat crop, and, further, that its effect is produced by 

 lengthening or shortening the growing season, particularly' that por- 

 tion of it during which the kernel is developing. A moderately cool 

 season, wi*h a liberal supply of moisture, has the effect of prolonging 

 the period during wliich the kernel is developing, thus favoring its 

 filling out with starch, the deposition of wliich is much greater at 

 that time than is that of nitrogenous material. With this goes an 

 increase in volume weight and an increased yield of grain per acre. 

 On the other hand, a hot, dr}- season shortens the period of kernel 

 development, curtails the deposition of starch, leaving the per- 



« Yearbook U. S. Department of Agriculture, 1901, pp. 299-308. 



^ Der Weizen in seinem Beziehungen zum Klima und das Gesetz der Korrelation, Berlin, 

 1893. 



f Abstract, Experiment Station Record, 13, p. 4.51, from Zhur. Opuitn. Agron., 1 (1900), 

 pp. 256-267. 



'^Agricultural Gazette of New South Wales, 12, pt. 2, pp. 1403-1424. 



