EFFECT OF TEMPERATURE AND OTHER METEORO- 

 LOGICAL FACTORS ON THE GROWTH OF SORGHUMS 



H. N. ViNALL, Agronomist, and H. R. Reed, Scientific Assistant, Office of Forage Crop 

 Investigations, Bureau of Plant Industry, United States Department of Agriculture 



HISTORICAL REVIEW 



The botanical group Andropogon sorghum includes an extensive and 

 widely varying list of cultivated crop plants which are primarily sub- 

 tropical in their climatic requirements, although many varieties are now 

 being grown well north in the temperate regions. The effect of temper- 

 ature and other meteorological factors on the sorghums has not been 

 discussed very extensively in agricultural literature. 



Sachs (5, p. 365)^ determined the minimum, optimum, and maximum 

 temperatures for wheat, barley, pumpkin, beans, and corn as follows: 



Plant. 



Wheat. .. 

 Barley. .. 

 Pumpkin 

 Beans. . . . 

 Com 



"F. 



108. 



99- 



"5- 



115. 



"5- 



The above figures, however, are for seedlings (germinating seeds), and 

 while the results are indicative, it is probably true that the more fully 

 developed plants would continue to grow under wider extremes. 



The. work of other investigators, Mayer, Heinrich, etc., indicate that 

 the optimum temperatures for the growth of the nasturtium (Tropaeolum 

 majus) , the water violet {Hoitonia palustris) , and white mustard (Sinapis 

 alba) also lie between 88° and 95° F. Bose (j, p. 445) found the opti- 

 mum temperature for the Crinum lily, the peduncle of the crocus, and 

 and the hypocotyl of the balsam to be 95° F. 



It would seem from these tests that the optimum temperature for a 

 considerable number of plants is between 83° and 95° F. From the 



1 Reference is made by number (italic) to " Literature cited," p. 147. 



Journal of Agricultural Research, 

 Washington, D. C. 



{^3,3) 



Vol. XIII, No. J 

 Apr. 8, 1918 

 Key No. G-140 



