INFLUENCE OF CLIMATE UPON COMPOSITION AND YIELD. 21 



Kornicke and Werner " cite an experiment in which winter wheat 

 grown in Poppelsdorf for several years was sent to and grown in the 

 moist cUmate of Great Britain, in Germany, and in the continental 

 climate of Russia (steppes) . The results were as follows : 



Locality. 



Great Britain. . . 



Germany 



Soutliem Russia 



Number 

 of exper- 

 iments. 



Weight (in grams) 

 of— 



Percentage of — 



37 

 18 

 19 



100 

 plants. 



600 

 500 

 365 



Kernels 

 from 100 

 plants. 



227 

 204 

 160 



Grain. 



37.8 

 40.8 

 44.0 



Straw. 



62.3 

 59.2 

 56.0 



These investigators conclude from the results that in a moist cli- 

 mate relatively more straw and less grain are produced than in a dr}", 

 warm climate. The thickness of the straw and the weight of the 

 kernels from 100 heads are greater, while the percentage by weight 

 of kernels to straw is much less in a moist climate. They also quote 

 Haberlandt as saying that a continental climate produces a small, 

 hard wheat kernel, rich in gluten and of especially heavy weight. 



Deherain and Dupont ^ report some interesting observations as to 

 the effect of climate on the composition of wheat. They state that the 

 harvest of 1888 at Grignon was late and the process of ripening slow. 

 There was a heavy yield of grain having a gluten content of 12.60 per 

 cent and a starch content of 77.2 per cent. The following season was 

 diy and hot, with a rapid ripening of the grain, resulting in a smaller 

 crop. The gluten content of the grain was 15.3 per cent and the 

 starch content 61.9 per cent. They removed the heads from a num- 

 ])er of plants. The next day the stems were harvested, as were also 

 an equal number of entire plants. The stems w^ithout heads showed 

 that carbohydrates equal to 5.94 per cent of the dry matter had been 

 formed. The stems on which the heads remained one day longer 

 contained 1.63 per cent carbohydrates. They argue from this that 

 the upper portion of the stem, provided it is still green, performs the 

 functions of the leaves in other plants and thus ela})orates the starch 

 that fills out the kernel in its later development. 



A report from the Ploti Experiment Station ' states that the con- 

 ditions that favored an increase in yield caused a reduction in the 

 relative proportion of nitrogen in the grain. Excessive humidity 

 favored the process of assimilation of carboh3'drates, while drought 

 hastened maturation and produced a grain relatively rich in proteids. 



"Handbuch des Getreidebaues, Berlin, 1884, pp. 69, 70. 

 ''Ann. Agron., 1902, p. 522. 



'.Abstract, Experiment Station Record, 14, p. 340, from Sept. Rap An. Sta. Expt. 

 Agron. Ploty, 1901, pp. xiv-180. 



